POWER DRIVER FOR STEPPER MOTORS INTEGRATED CIRCUITS TMC5031 DATASHEET Dual, cost-effective controller and driver for up to two 2-phase bipolar stepper motors. Integrated motion controller with SPI interface. APPLICATIONS CCTV, Security Antenna Positioning Heliostat Controller Battery powered applications Office Automation ATM, Cash recycler, POS Lab Automation Liquid Handling Medical Printer and Scanner Pumps and Valves FEATURES AND DESCRIPTION BENEFITS 2-phase stepper motors Drive Capability up to 2 x 1.1A coil current Motion Controller with sixPoint™ ramp Voltage Range 4.75… 16V DC SPI Interface 2x Ref.-Switch input per axis Highest Resolution 256 microsteps per full step Full Protection & Diagnostics stallGuard2™ high precision sensorless motor load detection coolStep™ load dependent current control for energy savings up to 75% spreadCycle™ high-precision chopper for best current sine wave form and zero crossing with additional chopSync2™ Compact Size 7x7mm QFN48 package BLOCK DIAGRAM The TMC5031 is a low cost motion controller and driver IC for up to two stepper motors. It combines two flexible ramp motion controllers with energy efficient stepper motor drivers. The drivers support two-phase stepper motors and offer an industry-leading feature set, including high-resolution microstepping, sensorless mechanical load measurement, load-adaptive power optimization, and low-resonance chopper operation. All features are controlled by a standard SPI™ interface. Integrated protection and diagnostic features support robust and reliable operation. High integration, high energy efficiency and small form factor enable miniaturized designs with low external component count for cost-effective and highly competitive solutions. 2x Ref. Switches TMC5031 Power Supply Charge Pump MOTION CONTROLLER with Linear 6 Point RAMP Generator Programmable 256 µStep Sequencer Motor 1 DRIVER 1 Protection & Diagnostics SPI Protection & Diagnostics MOTION CONTROLLER with Linear 6 Point RAMP Generator Programmable 256 µStep Sequencer stallGuard2 2x Ref. Switches TRINAMIC Motion Control GmbH & Co. KG Hamburg, Germany Motor 2 DRIVER 2 coolStep TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 2 APPLICATION EXAMPLES: HIGH FLEXIBILITY – MULTIPURPOSE USE The TMC5031 scores with power density, complete motion controlling features and integrated power stages. It offers a versatility that covers a wide spectrum of applications from battery systems up to embedded applications with 1.1A current per motor. The small form factor keeps costs down and allows for miniaturized layouts. Extensive support at the chip, board, and software levels enables rapid design cycles and fast time-to-market with competitive products. High energy efficiency and reliability from TRINAMIC’s coolStep technology deliver cost savings in related systems such as power supplies and cooling. MINIATURIZED DESIGN FOR UP TO TWO STEPPER MOTORS Ref. Switches High-Level Interface CPU SPI M TMC5031 Two reference switch inputs can be used for each motor. A single CPU controls the whole system, which is highly economical and space saving. Ref. Switches High-Level Interface CPU SPI M TMC5031 M Ref. Switches ORDER CODES Order code TMC5031-LA www.trinamic.com Description Dual stallGuard2™ and coolStep™ controller/driver, QFN48 Size 7 x 7 mm2 TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 3 TABLE OF CONTENTS 1 PRINCIPLES OF OPERATION 1.1 1.2 1.3 1.4 1.5 1.6 1.7 2 KEY CONCEPTS 4 SPI CONTROL INTERFACE 5 SOFTWARE 5 MOVING AND CONTROLLING THE MOTOR 5 PRECISION DRIVER WITH PROGRAMMABLE MICROSTEPPING WAVE 5 STALLGUARD2 – MECHANICAL LOAD SENSING 5 COOLSTEP – LOAD ADAPTIVE CURRENT CONTROL 6 PIN ASSIGNMENTS 2.1 2.2 3 PACKAGE OUTLINE SIGNAL DESCRIPTIONS SAMPLE CIRCUITS 3.1 3.2 3.3 3.4 4 STANDARD APPLICATION CIRCUIT 5 V ONLY SUPPLY EXTERNAL VCC SUPPLY OPTIMIZING ANALOG PRECISION SPI INTERFACE 4.1 4.2 4.3 5 SPI DATAGRAM STRUCTURE SPI SIGNALS TIMING REGISTER MAPPING 5.1 5.2 5.3 6 6.1 7 GENERAL CONFIGURATION REGISTERS RAMP GENERATOR REGISTERS MOTOR DRIVER REGISTERS 7.3 7.4 8 8.1 8.2 8.3 9 7 7 10 10 12 13 13 14 14 15 16 STALLGUARD2 LOAD MEASUREMENT 10.1 10.2 10.3 10.4 11 11.1 11.2 11.3 12 SPREADCYCLE 2-PHASE MOTOR CHOPPER 34 CLASSIC 2-PHASE MOTOR CONSTANT OFF TIME CHOPPER 36 RANDOM OFF TIME 37 CHOPSYNC2 FOR QUIET MOTORS 38 DRIVER DIAGNOSTIC FLAGS 39 TEMPERATURE MEASUREMENT SHORT TO GND PROTECTION OPEN LOAD DIAGNOSTICS 39 39 39 USER BENEFITS MICROSTEP TABLE CLOCK OSCILLATOR AND CLOCK INPUT 13.1 CONSIDERATIONS ON THE FREQUENCY 42 43 44 45 46 46 46 47 47 47 49 50 50 50 52 52 14 ABSOLUTE MAXIMUM RATINGS 53 15 ELECTRICAL CHARACTERISTICS 53 15.3 32 USER BENEFITS SETTING UP FOR COOLSTEP TUNING COOLSTEP SINE-WAVE LOOK-UP TABLE 12.1 12.2 13 TUNING THE STALLGUARD2 THRESHOLD SGT STALLGUARD2 MEASUREMENT FREQUENCY AND FILTERING DETECTING A MOTOR STALL LIMITS OF STALLGUARD2 OPERATION COOLSTEP OPERATION 18 19 24 31 www.trinamic.com 10 VELOCITY THRESHOLDS REFERENCE SWITCHES 15.1 15.2 SENSE RESISTORS REAL WORLD UNIT CONVERSION RAMP GENERATOR FUNCTIONALITY 9.3 9.4 17 30 RAMP GENERATOR 9.1 9.2 7 CURRENT SETTING CHOPPER OPERATION 7.1 7.2 4 16 LAYOUT CONSIDERATIONS 16.1 16.2 16.3 16.4 17 EXPOSED DIE PAD WIRING GND SUPPLY FILTERING LAYOUT EXAMPLE PACKAGE MECHANICAL DATA 17.1 17.2 18 OPERATIONAL RANGE DC CHARACTERISTICS AND TIMING CHARACTERISTICS THERMAL CHARACTERISTICS DIMENSIONAL DRAWINGS PACKAGE CODES GETTING STARTED 18.1 INITIALIZATION EXAMPLES 53 54 56 57 57 57 57 58 59 59 59 60 60 19 DISCLAIMER 61 20 ESD SENSITIVE DEVICE 61 40 21 TABLE OF FIGURES 62 40 40 22 REVISION HISTORY 63 23 REFERENCES 63 TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 4 1 Principles of Operation REFL1 REFR1 ref. / stop switches motor 1 +VM F tor p mo e t S l coo river d F reference switch processing VCP CPI 100n charge pump CPO VSA 5VOUT 100n 5V Voltage regulator VCC 4.7µ programmable sine table 4*256 entry Step & Direction pulse generation 2x linear 6 point RAMP generator 22n 100n DRV_ENN TMC5031 Dual stepper motor driver / controller x Half Bridge 1 Half Bridge 1 O1A1 O1A2 S N chopper O1B1 Half Bridge 2 Half Bridge 2 trol n co n Motio Stepper #1 +VM VS 2 phase stepper motor O1B2 BR1A / B coolStep™ RSENSE RSENSE GNDP stallGuard2™ CSN SCK SDI SDO SPI™ Control register set interrupt out opt. ext. clock 12-16MHz +VIO 3.3V or 5V I/O voltage PP 2 x current comparator temperature measurement 2 x DAC RSENSE=0R25 allows for maximum coil current SPI interface f ace Inter INT & position pulse output CLK oscillator/ selector Stepper driver Protection & diagnostics 2 x current comparator ol contr n GNDP RSENSE BR2A / B 2x linear 6 point RAMP generator Half Bridge 2 Half Bridge 2 Step & Direction pulse generation programmable sine table 4*256 entry chopper O2A2 Half Bridge 1 Half Bridge 1 S N O2A1 VS F = 60ns spike filter 100n +VM 2 phase stepper motor Stepper #2 DRV_ENN GND GNDA REFR2 DIE PAD F REFL2 TST_MODE F O2B2 O2B1 x otor ep m t S l o co r drive reference switch processing 100n RSENSE coolStep™ CLK_IN VCC_IO 2 x DAC stallGuard2™ Motio INT SINGLEDRV ref. / stop switches motor 2 opt. driver enable Figure 1.1 Basic application and block diagram The TMC5031 motion controller and driver chip is an intelligent power component interfacing between the CPU and up to two stepper motors. The TMC5031 offers a number of unique enhancements which are enabled by the system-on-chip integration of driver and controller. The sixPoint ramp generator of the TMC5031 uses coolStep and stallGuard2 automatically to optimize every motor movement: TRINAMICs special features contribute toward lower system cost, greater precision, greater energy efficiency, smoother motion, and cooler operation in stepper motor applications. The clear concept and the comprehensive solution save design-in time. 1.1 Key Concepts The TMC5031 implements several advanced features which are exclusive to TRINAMIC products. These features contribute toward greater precision, greater energy efficiency, higher reliability, smoother motion, and cooler operation in many stepper motor applications. stallGuard2™ High-precision load measurement using the back EMF on the motor coils. coolStep™ Load-adaptive current control which reduces energy consumption by as much as 75%. spreadCycle™ High-precision chopper algorithm available as an alternative to the traditional constant off-time algorithm. In addition to these performance enhancements, TRINAMIC motor drivers also offer safeguards to detect and protect against shorted outputs, output open-circuit, overtemperature, and undervoltage conditions for enhancing safety and recovery from equipment malfunctions. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 5 1.2 SPI Control Interface The SPI interface is a bit-serial interface synchronous to a bus clock. For every bit sent from the bus master to the bus slave, another bit is sent simultaneously from the slave to the master. Communication between an SPI master and the TMC5031 slave always consists of sending one 40-bit command word and receiving one 40-bit status word. The SPI command rate typically is a few commands per complete motor motion. 1.3 Software From a software point of view the TMC5031 is a peripheral with a number of control and status registers. Most of them can either be written only or read only, some of the registers allow both read and write access. In case read-modify-write access is desired for a write only register, a shadow register can be realized in master software. 1.4 Moving and Controlling the Motor 1.4.1 Integrated Motion Controller The integrated 32 bit motion controller automatically drives the motors to target positions, or accelerates to target velocities. All motion parameters can be changed on the fly with the motion controller recalculating immediately. A minimum set of configuration data consists of acceleration and deceleration values and the maximum motion velocity. A start and stop velocity is supported as well as a second acceleration and deceleration setting. It supports immediate reaction to mechanical reference switches and to the sensorless stall detection stallGuard2. Benefits are: Flexible ramp programming Efficient use of motor torque for acceleration and deceleration allows higher machine throughput Immediate reaction to stop and stall conditions 1.5 Precision Driver with Programmable Microstepping Wave Current into the motor coils is controlled using a cycle-by-cycle chopper mode. Two chopper modes are available: a traditional constant off-time mode and the new spreadCycle mode. Constant off-time mode provides higher torque at the highest velocity, while spreadCycle mode offers smoother operation and greater power efficiency over a wide range of speed and load. The spreadCycle chopper scheme automatically integrates a fast decay cycle and guarantees smooth zero crossing performance. Programmable microstep shapes allow optimizing the motor performance. Benefits are: - Significantly improved microstepping with low cost motors - Motor runs smooth and quiet - Reduced mechanical resonances yields improved torque 1.6 stallGuard2 – Mechanical Load Sensing stallGuard2 provides an accurate measurement of the load on the motor. It can be used for stall detection as well as other uses at loads below those which stall the motor, such as coolStep loadadaptive current reduction. This gives more information on the drive allowing functions like sensorless homing and diagnostics of the drive mechanics. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 6 1.7 coolStep – Load Adaptive Current Control coolStep drives the motor at the optimum current. It uses the stallGuard2 load measurement information to adjust the motor current to the minimum amount required in the actual load situation. This saves energy and keeps the components cool, making the drive an efficient and precise solution. Energy efficiency Motor generates less heat Less or no cooling Use of smaller motor - power consumption decreased up to 75%. improved mechanical precision. improved reliability and lower cost infrastructure. less torque reserve required, lower cost motor. Figure 1.2 shows the efficiency gain of a 42mm stepper motor when using coolStep compared to standard operation with 50% of torque reserve. coolStep is enabled above 60RPM in the example. 0,9 Efficiency with coolStep 0,8 Efficiency with 50% torque reserve 0,7 0,6 0,5 Efficiency 0,4 0,3 0,2 0,1 0 0 50 100 150 200 250 300 350 Velocity [RPM] Figure 1.2 Energy efficiency with coolStep (example) www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 7 2 Pin Assignments O1B1 BR1B O1B2 - VCP 41 40 39 38 37 VS 44 GNDP O1A2 45 VS BR1A 46 42 O1A1 47 43 TST_MODE 48 2.1 Package Outline INT 1 36 CPI PP 2 35 CSN 3 34 CPO GND SCK 4 33 VCC SDI 5 32 5VOUT 31 GNDA 30 VSA TMC 5031-LA QFN48 7mm x 7mm 0.5 pitch 21 22 23 24 O2B2 - GND REFR2 20 REFL2 25 O2B1 BR2B 26 12 19 11 VS CLK GND 18 REFR1 GNDP 27 17 10 VS REFL1 GND 16 GND O2A2 DRV_ENN 28 15 29 9 BR2A 8 13 SDO 14 7 - 6 O2A1 GND VCC_IO Figure 2.1 TMC5031 pin assignments. 2.2 Signal Descriptions Pin GND VCC_IO Number Type 6, 9, 10, GND 12, 24, 34 7 VSA 30 GNDA 5VOUT 31 32 VCC 33 www.trinamic.com GND Function Digital ground pin for IO pins and digital circuitry. 3.3V or 5V I/O supply voltage pin for all digital inputs and outputs. May be supplied from 5VOUT pin in stand-alone operation, where no I/O voltage supply is available. Analog high voltage supply for linear regulator and internal references – typically supplied with driver supply voltage. Provide 100nF blocking capacitor to GND. Avoid excessive voltage ripple. Analog GND Output of internal 5 V linear regulator, supply voltage for internal analog circuitry and reference for coil current regulators. An external capacitor to GNDA close to the pin is required. 4.7 µF ceramic are recommended to keep ripple below a few mV, especially when used to supply VCC. Optional RC filtering can be used to decouple VCC ripple from this pin (3.3 Ω recommended). Digital core power supply. Normally supplied by 5VOUT pin. In case, a different 5 V supply is used, or RC-filtering is applied, provide a 470 nF or larger blocking capacitor to GND. TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) Pin DIE_PAD Number - Type GND Function The exposed die attach pad is the thermal cooling pad for the IC and shall be soldered to a ground pad, and be directly electrically tied together with all GND pins. Use a large number of thermally conducting vias to a PCB ground plane for best thermal and electrical performance. The ground plane also acts as a heat spreader to reduce thermal junction to ambient resistance. Table 2.1 Low voltage digital and analog power supply pins Pin CPO Number 35 Type O(VCC) CPI 36 I(VCP) VCP 37 Function Charge pump driver output. Outputs 5V (GND to VCC) square wave with 1/16 of internal oscillator frequency. Charge pump capacitor input: Provide external 22 nF / 50 V capacitor to CPO. Output of charge pump. Provide external 100 nF capacitor to VS. Table 2.2 Charge pump pins Pin INT PP CSN SCK SDI SDO CLK Number 1 2 3 4 5 8 11 Type O (Z) O (Z) I I I O (Z) I REFR2 REFL2 REFR1 REFL1 DRV_ENN 25 26 27 28 29 I I I I I TST_MODE 48 I - 13, 23, 38 N.C. Function Tristate interrupt output based on ramp generator flags 4, 5, 6 & 7. Tristate position compare output for motor 1 (poscmp_enable=1). Chip select input of SPI interface Serial clock input of SPI interface Data input of SPI interface Tristate data output of SPI interface (enabled with CSN=0) Clock input for all internal operations. Tie low to use internal oscillator. A high signal disables the internal oscillator until power down. Right reference switch input for motor 2 Left reference switch input for motor 2 Right reference switch input for motor 1 Left reference switch input for motor 1 Enable (not) input for drivers (tie to GND). Switches off all motor outputs (set high for disable). Test mode input. Puts IC into test mode. Tie to GND for normal operation. Unused pins – no internal electrical connection. Leave open or tie to GND for compatibility with future devices. Table 2.3 Digital I/O pins (all related to VCC_IO supply) www.trinamic.com 8 TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) Pin O2A1 BR2A Number 14 15 Type O (VS) O2A2 VS 16 17, 19 O (VS) GNDP O2B1 BR2B 18 20 21 GND O (VS) O2B2 O1B2 BR1B 22 39 40 O (VS) O (VS) O1B1 VS 41 42, 44 O (VS) GNDP O1A2 BR1A 43 45 46 GND O (VS) O1A1 47 O (VS) Table 2.4 Power driver pins www.trinamic.com Function Motor 2 A1 output (stepper motor coil A) Motor 2 bridge A negative power supply and current sense input. Provide external sense resistor to GND. Motor 2 A2 output (stepper motor coil A) Driver 2 positive power supply. Connect to VS and provide sufficient filtering capacity for chopper current ripple. Power GND for driver 2. Connect to GND. Motor 2 B1 output (stepper motor coil B) Motor 2 bridge B negative power supply and current sense input. Provide external sense resistor to GND. Motor 2 B2 output (stepper motor coil B) Motor 1 B2 output (stepper motor coil B) Motor 1 bridge B negative power supply and current sense input. Provide external sense resistor to GND. Motor 1 B1 output (stepper motor coil B) Driver 1 positive power supply. Connect to VS and provide sufficient filtering capacity for chopper current ripple. Power GND for driver 1. Connect to GND. Motor 1 A2 output (stepper motor coil A) Motor 1 bridge A negative power supply and current sense input. Provide external sense resistor to GND. Motor 1 A1 output (stepper motor coil A) 9 TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 10 3 Sample Circuits The sample circuits show the connection of the external components in different operation and supply modes. The standard application circuit uses a minimum set of additional components in order to operate the motor. The connection of the bus interface and further digital signals is left out for clarity. REFR1 CPO CPI 22n REFL1 3.1 Standard Application Circuit +VM +VM VS 5VOUT 100n 100n O1A1 Full Bridge A 5V Voltage regulator O1A2 4.7µ Controller 1 Driver 1 Full Bridge B N stepper motor #1 N stepper motor #2 O1B2 BR1A BR1B TMC5031 SPI interface S O1B1 VCC CSN SCK SDI SDO 100µF RS1A VSA reference switch processing RS1B charge pump DRV_ENN VCP 100n VS +VM 100n O2A1 Full Bridge A O2A2 PP Controller 2 Driver 2 O2B1 INT & position pulse output Full Bridge B O2B2 CLK_IN 5V VCC_IO BR2B GNDP GND GNDA DIE PAD DRV_ENN REFR2 REFL2 100n TST_MODE 3.3V TS3480 CX33*) BR2A reference switch processing RS2A INT RS2B optional external clock 12-16MHz S *) For a reliable start-up it is essential that VCC_IO comes up to a minimum of 1.5V before the TMC5031 leaves the reset condition. Therefore, TRINAMIC recommends using a fast-start-up voltage regulator (e.g. TS3480CX33) in a 3.3V environment. Figure 3.1 Standard application circuit In order to minimize linear voltage regulator power dissipation of the internal 5V voltage regulator in an application where VM is high, a different (lower) supply voltage can be used for VSA, if available. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 11 3.1.1 VCC_IO Requirements For a reliable start-up it is essential that VCC_IO comes up to a minimum of 1.5V before the TMC5031 leaves the reset condition. The reset condition ends earliest 50µs after the time when VSA exceeds its undervoltage threshold of typically 4.2V, or when 5VOUT exceeds its undervoltage threshold of typically 3.5V, whichever comes last. THERE ARE THREE WAYS TO COME UP TO VCC_IO REQUIREMENTS - 5VOUT can be used directly to supply VCC_IO. In this case there are no further requirements. - An external low drop regulator can be used in a 3.3V environment as shown in Figure 3.1. Note, that most voltage regulators are not suitable for this application because they show a delayed boot up. The following external regulators are proved by TRINAMIC: This regulator can be used within the full supply voltage range when tied to the motor supply voltage. This regulator can be used to supply VCC_IO from 5VOUT, or from a supply voltage of up to 15V. TS3480CX33 LD1117-3.3 VCC_IO can be supplied externally as shown in Figure 3.2 . In this case it is mandatory to connect the Schottky diode to the logic supply of the external circuitry. Please note, that the 2K resistor is not to be used with 5V I/O voltage. CPI 22n CPO - +VM VCP charge pump 100n VSA 5VOUT 100n 4.7µ 5V Voltage regulator 2R2 VCC +VCC_IO 1K VCC_IO MSS1P3 2K 22n 470n 3.3V, only Figure 3.2 External supply of VCC_IO (showing optional filtering for VCC) Refer to application note no. 028 Supply Voltage Considerations: VCC_IO in TMC50xx Designs (www.trinamic.com). Here you will find complete information about connecting VCC_IO. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 12 REFR1 REFL1 CPI 22n CPO 3.2 5 V Only Supply +5V VS +5V VSA 5VOUT 100n O1A1 Full Bridge A 5V Voltage regulator 4.7µ O1A2 Controller 1 Driver 1 Full Bridge B N stepper motor #1 N stepper motor #2 O1B2 470n BR1A BR1B TMC5031 SPI interface S O1B1 VCC CSN SCK SDI SDO 100µF VS RS1A 100n reference switch processing RS1B charge pump DRV_ENN VCP +5V 100n O2A1 Full Bridge A O2A2 PP Controller 2 Driver 2 O2B1 INT & position pulse output Full Bridge B O2B2 CLK_IN BR2A reference switch processing VCC_IO BR2B RS2A VCC_IO 5V INT RS2B Optional external clock 12-16MHz S 100n GNDP GND GNDA DIE PAD DRV_ENN REFR2 REFL2 TST_MODE VCC_IO 3.3V see standard application schematic Figure 3.3 5V only operation While the standard application circuit is limited to roughly 5.5 V lower supply voltage, a 5 V only application lets the IC run from a normal 5 V +/-10% supply. In this application, linear regulator drop must be minimized. Therefore, the major 5 V load is removed by supplying VCC directly from the external supply. In order to keep supply ripple away from the analog voltage reference, 5VOUT should have an own filtering capacity and the 5VOUT pin does not become bridged to the 5V supply. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 13 3.3 External VCC Supply Supplying VCC from an external supply is advised, when cooling of the chip is critical, e.g. at high environment temperatures in combination with high supply voltages (16 V), as the linear regulator is a major source of on-chip power dissipation. It must be made sure that the external VCC supply comes up before or synchronously with the 5VOUT supply, because otherwise the power-up reset event may be missed by the TMC5031. A diode from 5VOUT to VCC ensures this, in case the external voltage regulator is not a low drop type linear regulator. In order to prevent overload of the internal 5V regulator when using this diode, an additional series resistor has been added to VSA. CPI 22n CPO An alternative for reduced power dissipation is using a lower supply voltage for VSA, e.g. 6V to 12V. If power dissipation is critical, but no external supply is available, the clock frequency can be reduced as a first step by supplying external 12 MHz clock. The diode is mandatory to satisfy power-up conditions! +VM VCP charge pump 100n 220R VSA 5V Voltage regulator 5VOUT +5V 100n 4.7µ VCC LL4148 470n Figure 3.4 Using an external 5V supply to reduce linear regulator power dissipation 3.4 Optimizing Analog Precision CPI 22n CPO The 5VOUT pin is used as an analog reference for operation of the TMC5031. Performance will degrade when there is voltage ripple on this pin. Most of the high frequency ripple in a TMC5031 design results from the operation of the internal digital logic. The digital logic switches with each edge of the clock signal. Further, ripple results from operation of the charge pump, which operates with roughly 1 MHz and draws current from the VCC pin. In order to keep this ripple as low as possible, an additional filtering capacitor can be put directly next to the VCC pin with vias to the GND plane giving a short connection to the digital GND pins (pin 6 and pin 34). Analog performance is best, when this ripple is kept away from the analog supply pin 5VOUT, using an additional series resistor of 2.2 Ω to 3.3 Ω. The voltage drop on this resistor will be roughly 100 mV (IVCC * R). +VM VCP charge pump 100n VSA 5VOUT 100n 5V Voltage regulator GNDA 4.7µ 2R2 VCC 470n Figure 3.5 Adding an RC-Filter on VCC for reduced ripple www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 14 4 SPI Interface 4.1 SPI Datagram Structure The TMC5031 uses 40 bit SPI™ (Serial Peripheral Interface, SPI is Trademark of Motorola) datagrams for communication with a microcontroller. Microcontrollers which are equipped with hardware SPI are typically able to communicate using integer multiples of 8 bit. The NCS line of the TMC5031 must be handled in a way, that it stays active (low) for the complete duration of the datagram transmission. Each datagram sent to the TMC5031 is composed of an address byte followed by four data bytes. This allows direct 32 bit data word communication with the register set of the TMC5031. Each register is accessed via 32 data bits even if it uses less than 32 data bits. For simplification, each register is specified by a one byte address: - For a read access the most significant bit of the address byte is 0. - For a write access the most significant bit of the address byte is 1. Most registers are write only registers, some can be read additionally, and there are also some read only registers. TMC5031 SPI DATAGRAM STRUCTURE MSB (transmitted first) 40 bit 39 ... 8 bit address 8 bit SPI status ... 0 32 bit data 39 ... 32 to TMC5031: RW + 7 bit address from TMC5031: 8 bit SPI status W 39 / 38 ... 32 38...32 LSB (transmitted last) 31 ... 0 8 bit data 8 bit data 31 ... 24 31...28 27...24 23 ... 16 23...20 19...16 8 bit data 8 bit data 15 ... 8 15...12 7 ... 0 11...8 7...4 3...0 3 3 3 3 3 3 3 3 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 4.1.1 Selection of Write / Read (WRITE_notREAD) The read and write selection is controlled by the MSB of the address byte (bit 39 of the SPI datagram). This bit is 0 for read access and 1 for write access. So, the bit named W is a WRITE_notREAD control bit. The active high write bit is the MSB of the address byte. So, 0x80 has to be added to the address for a write access. The SPI interface always delivers data back to the master, independent of the W bit. The data transferred back is the data read from the address which was transmitted with the previous datagram, if the previous access was a read access. If the previous access was a write access, then the data read back mirrors the previously received write data. So, the difference between a read and a write access is that the read access does not transfer data to the addressed register but it transfers the address only and its 32 data bits are dummies, and, further the following read or write access delivers back the data read from the address transmitted in the preceding read cycle. A read access request datagram uses dummy write data. Read data is transferred back to the master with the subsequent read or write access. Hence, reading multiple registers can be done in a pipelined fashion. Whenever data is read from or written to the TMC5031, the MSBs delivered back contain the SPI status, SPI_STATUS, a number of eight selected status bits. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 15 Example: For a read access to the register (X_ACTUAL) with the address 0x21, the address byte has to be set to 0x21 in the access preceding the read access. For a write access to the register (V_ACTUAL), the address byte has to be set to 0x80 + 0x22 = 0xA2. For read access, the data bit might have any value (-). So, one can set them to 0. action read X_ACTUAL read X_ACTUAL write V_ACTUAL:= 0x00ABCDEF write V_ACTUAL:= 0x00123456 data sent to TMC5031 0x2100000000 0x2100000000 0xA200ABCDEF 0xA200123456 data received from TMC5031 0xSS & unused data 0xSS & X_ACTUAL 0xSS & X_ACTUAL 0xSS00ABCDEF *)S: is a placeholder for the status bits SPI_STATUS 4.1.2 SPI Status Bits Transferred with Each Datagram Read Back SPI_STATUS – status flags transmitted with each SPI access in bits 39 to 32 Bit 7 6 5 4 3 2 1 0 Name Comment status_stop_l(2) status_stop_l(1) velocity_reached(2) velocity_reached(1) driver_error(2) driver_error(1) reset_flag reserved (0) RAMP_STATUS2[0] – 1: Signals motor 2 stop left switch status RAMP_STATUS1[0] – 1: Signals motor 1 stop left switch status RAMP_STATUS2[8] – 1: Signals motor 2 has reached its target velocity RAMP_STATUS1[8] – 1: Signals motor 1 has reached its target velocity GSTAT[2] – 1: Signals driver 2 driver error (clear by reading GSTAT) GSTAT[1] – 1: Signals driver 1 driver error (clear by reading GSTAT) GSTAT[0] – 1: Signals, that a reset has occurred (clear by reading GSTAT) 4.1.3 Data Alignment All data are right aligned. Some registers represent unsigned (positive) values, some represent integer values (signed) as two’s complement numbers, single bits or groups of bits are represented as single bits respectively as integer groups. 4.2 SPI Signals The SPI bus on the TMC5031 has four signals: - SCK – bus clock input - SDI – serial data input - SDO – serial data output - CSN – chip select input (active low) The slave is enabled for an SPI transaction by a low on the chip select input CSN. Bit transfer is synchronous to the bus clock SCK, with the slave latching the data from SDI on the rising edge of SCK and driving data to SDO following the falling edge. The most significant bit is sent first. A minimum of 40 SCK clock cycles is required for a bus transaction with the TMC5031. If more than 40 clocks are driven, the additional bits shifted into SDI are shifted out on SDO after a 40-clock delay through an internal shift register. This can be used for daisy chaining multiple chips. CSN must be low during the whole bus transaction. When CSN goes high, the contents of the internal shift register are latched into the internal control register and recognized as a command from the master to the slave. If more than 40 bits are sent, only the last 40 bits received before the rising edge of CSN are recognized as the command. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 16 4.3 Timing The SPI interface is synchronized to the internal system clock, which limits the SPI bus clock SCK to half of the system clock frequency. If the system clock is based on the on-chip oscillator, an additional 10% safety margin must be used to ensure reliable data transmission. All SPI inputs as well as the ENN input are internally filtered to avoid triggering on pulses shorter than 20ns. Figure 4.1 shows the timing parameters of an SPI bus transaction, and the table below specifies their values. CSN tCC tCL tCH tCH tCC SCK tDU SDI bit39 tDH bit38 bit0 tDO SDO tZC bit39 bit38 bit0 Figure 4.1 SPI timing SPI interface timing Parameter SCK valid before or after change of CSN AC-Characteristics clock period: tCLK Symbol tCC fSCK fSCK assumes synchronous CLK tCSH SCK low time tCL SCK high time tCH www.trinamic.com Min Typ Max 10 *) Min time is for synchronous CLK with SCK high one tCH before CSN high only *) Min time is for synchronous CLK only *) Min time is for synchronous CLK only assumes minimum OSC frequency CSN high time SCK frequency using internal clock SCK frequency using external 16MHz clock SDI setup time before rising edge of SCK SDI hold time after rising edge of SCK Data out valid time after falling SCK clock edge SDI, SCK and CSN filter delay time Conditions Unit ns tCLK*) >2tCLK+10 ns tCLK*) >tCLK+10 ns tCLK*) >tCLK+10 ns 4 MHz 8 MHz tDU 10 ns tDH 10 ns tDO no capacitive load on SDO tFILT rising and falling edge 12 20 tFILT+5 ns 30 ns TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 17 5 Register Mapping This chapter gives an overview of the complete register set. Some of the registers bundling a number of single bits are detailed in extra tables. The functional practical application of the settings is detailed in dedicated chapters. Note - All registers become reset to 0 upon power up, unless otherwise noted. - Add 0x80 to the address Addr for write accesses! NOTATION OF HEXADECIMAL AND BINARY NUMBERS 0x % precedes a hexadecimal number, e.g. 0x04 precedes a multi-bit binary number, e.g. %100 NOTATION OF R/W FIELD R W R/W R+C Read only Write only Read- and writable register Clear upon read OVERVIEW REGISTER MAPPING REGISTER DESCRIPTION General Configuration Registers These registers contain global configuration, global status flags, slave address configuration. This register set offers registers for choosing a ramp mode, choosing velocities, homing, acceleration and deceleration, and target positioning. This register set offers registers for driver current control, setting thresholds for coolStep operation, setting thresholds for different chopper modes, and a reference switch and stallGuard2 event configuration register and (with separate table) a ramp and reference switch status register (with separate table). This register set offers registers for setting / reading out microstep table and counter (see separate table, too), chopper and driver configuration (see separate tables for different motor types, too), coolStep and stallGuard2 configuration (see separate table, too), and reading out stallGuard2 values and driver error flags (see separate table, too). Ramp Generator Motion Control Register Set Ramp Generator Driver Feature Control Register Set Motor Driver Register Set www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 18 5.1 General Configuration Registers GENERAL CONFIGURATION REGISTERS (0X00…0X1F) R/W Addr n Register Description / bit names Bit GCONF – Global configuration flags 0..2 Reserved, set to 0 3 poscmp_enable 0: Outputs INT and PP are tristated. 1: Position compare pulse (PP) and interrupt output (INT) are available 4..6 7 RW 0x00 11 GCONF 8 9 10 Bit 0 1 R+C 0x01 4 GSTAT 2 3 Bit 3..0 W 0x03 4 TEST_SEL R 0x04 8 + 8 INPUT W 0x05 32 X_COMPARE Attention: Not for user, set to 0 for normal operation! shaft1 1: Inverse motor 1 direction shaft2 1: Inverse motor 2 direction lock_gconf 1: GCONF is locked against further write access. GSTAT – Global status flags reset 1: Indicates that the IC has been reset since the last read access to GSTAT. drv_err1 1: Indicates, that driver 1 has been shut down due to an error since the last read access. drv_err2 1: Indicates, that driver 2 has been shut down due to an error since the last read access. uv_cp 1: Indicates an undervoltage on the charge pump. The driver is disabled in this case. SLAVECONF TEST_SEL: selects the function of REFR2 in test mode: 0…4: T120, DAC1, VDDH1, DAC2, VDDH2 Attention: Not for user, set to 0 for normal operation! Bit INPUT 0..6 Unused, ignore these bits 7 Reads the state of the DRV_ENN pin 31.. VERSION: 0x01=first version of the IC 24 Position comparison register for motor 1 position strobe. Activate poscmp_enable to get position pulse on output PP. XACTUAL = X_COMPARE: - www.trinamic.com Attention – do not leave the ouputs floating in tristate condition, provide an external pull-up or set this bit 1. Reserved, set to 0 test_mode 0: Normal operation 1: Enable analog test output on pin REFR2 TEST_SEL selects the function of REFR2: 0…4: T120, DAC1, VDDH1, DAC2, VDDH2 Output PP becomes high. It returns to a low state, if the positions mismatch. TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 19 5.2 Ramp Generator Registers Addresses Addr are specified for motor 1 (upper value) and motor 2 (second address). 5.2.1 Ramp Generator Motion Control Register Set RAMP GENERATOR MOTION CONTROL REGISTER SET (MOTOR 1: 0X20…0X2D, MOTOR 2: 0X40…0X4D) R/W Addr n Register RW 0x20 0x40 2 RAMPMODE RW 0x21 0x41 32 XACTUAL R 0x22 0x42 24 VACTUAL W 0x23 0x43 18 VSTART W 0x24 0x44 16 A1 W 0x25 0x45 20 V1 W W W W W 0x26 0x46 16 0x27 0x47 23 0x28 0x48 16 0x2A 0x4A 0x2B 0x4B Description / bit names RAMPMODE: 0: Positioning mode (using all A, D and V parameters) 1: Velocity mode to positive VMAX (using AMAX acceleration) 2: Velocity mode to negative VMAX (using AMAX acceleration) 3: Hold mode (velocity remains unchanged, unless stop event occurs) Actual motor position (signed) Hint: This value normally should only be modified, when homing the drive. In positioning mode, modifying the register content will start a motion. Actual motor velocity from ramp generator (signed) Motor start velocity (unsigned) 0: Disables A1 and D1 phase, use AMAX, VMAX only Second acceleration between V1 and VMAX (unsigned) 0…(2^16)-1 [µsteps / ta²] This is the acceleration and deceleration value for velocity mode. Second acceleration phase target velocity VMAX > V1, VMAX > VSTART (unsigned) 0…(2^23)-512 [µsteps / t] AMAX VMAX DMAX This is the target velocity in velocity mode. It can be changed any time during a motion. Deceleration between VMAX and V1 (unsigned) between V1 and VSTOP 0…(2^16)-1 [µsteps / ta²] 1…(2^16)-1 [µsteps / ta²] D1 VSTOP Attention: Set VSTOP ≥ VSTART! Attention: Do not set 0 in positioning mode! www.trinamic.com +-(2^23)-1 [µsteps / t] 0…(2^18)-1 [µsteps / t] 0…(2^16)-1 [µsteps / ta²] 0…(2^20)-1 [µsteps / t] Attention: Do not set 0 in positioning mode, even if V1=0! Motor stop velocity (unsigned) 18 -2^31… +(2^31)-1 Set VSTOP ≥ VSTART! First acceleration between VSTART and V1 (unsigned) First acceleration / deceleration phase target velocity (unsigned) Deceleration (unsigned) 16 Range [Unit] 0…3 1…(2^18)-1 [µsteps / t] TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 20 RAMP GENERATOR MOTION CONTROL REGISTER SET (MOTOR 1: 0X20…0X2D, MOTOR 2: 0X40…0X4D) R/W Addr n Register W 0x2C 0x4C 16 TZEROWAIT Description / bit names Waiting time after ramping down to zero velocity before next movement or direction inversion can start and before motor power down starts. Time range is about 0 to 2 seconds. This setting avoids excess acceleration e.g. from VSTOP to -VSTART. Target position for ramp mode (signed). Write a new target position to this register in order to activate the ramp generator positioning in RAMPMODE=0. Initialize all velocity, acceleration and deceleration parameters before. RW 0x2D 0x4D 32 XTARGET Hint: The position is allowed to wrap around, thus, XTARGET value optionally can be treated as an unsigned number. Hint: The maximum possible displacement is +/-((2^31)-1). Hint: When increasing V1, D1 or DMAX during a motion, rewrite XTARGET afterwards in order to trigger a second acceleration phase, if desired. www.trinamic.com Range [Unit] 0…(2^16)-1 * 512 tCLK -2^31… +(2^31)-1 TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 21 5.2.2 Ramp Generator Driver Feature Control Register Set RAMP GENERATOR DRIVER FEATURE CONTROL REGISTER SET (MOTOR 1: 0X30…0X36, MOTOR 2: 0X50…0X56) R/W W Addr n 0x30 0x50 5 + 5 + 4 Register IHOLD_IRUN Description / bit names Bit IHOLD_IRUN – Driver current control 4..0 IHOLD Standstill current (0=1/32…31=32/32) 12..8 IRUN Motor run current (0=1/32…31=32/32) 19..16 Hint: Choose sense resistors in a way, that normal IRUN is 16 to 31 for best microstep performance. IHOLDDELAY Controls the number of clock cycles for motor power down after a motion as soon as T_ZEROWAIT has expired. The smooth transition avoids a motor jerk upon power down. 0: 1..15: W 0x31 0x51 instant power down Delay per current reduction step in multiple of 2^18 clocks This is the lower threshold velocity for switching on smart energy coolStep. (unsigned) Set this parameter to disable coolStep at low speeds, where it cannot work reliably. 23 VCOOLTHRS VHIGH ≥ |VACT| ≥ VCOOLTHRS: - coolStep is enabled, if configured (Only bits 22..8 are used for value and for comparison) This velocity setting allows velocity dependent switching into a different chopper mode and fullstepping to maximize torque. (unsigned) W RW R+C R 0x32 0x52 0x34 0x54 0x35 0x55 0x36 0x56 23 11 14 32 VHIGH SW_MODE RAMP_STAT XLATCH |VACT| ≥ VHIGH: - coolStep is disabled (motor runs with normal current scale) - If vhighchm is set, the chopper switches to chm=1 with TFD=0 (constant off time with slow decay, only). - chopSync2 is switched off (SYNC=0) - If vhighfs is set, the motor operates in fullstep mode. (Only bits 22..8 are used for value and for comparison) Switch mode configuration See separate table! Ramp status and switch event status See separate table! Ramp generator latch position, latches XACTUAL upon a programmable switch event (see SW_MODE). time reference t for velocities: t = 2^24 / fCLK time reference ta² for accelerations: ta² = 2^41 / (fCLK)² www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 22 6.2.2.1 SW_MODE – Reference Switch and stallGuard2 Event Configuration Register 0X34, 0X54: SW_MODE – REFERENCE SWITCH AND STALLGUARD2 EVENT CONFIGURATION REGISTER Bit 11 Name en_softstop Comment 0: Hard stop 1: Soft stop The soft stop mode always uses the deceleration ramp settings DMAX, V1, D1, VSTOP and TZEROWAIT for stopping the motor. A stop occurs when the velocity sign matches the reference switch position (REFL for negative velocities, REFR for positive velocities) and the respective switch stop function is enabled. A hard stop also uses TZEROWAIT before the motor becomes released. 10 sg_stop 9 8 latch_r_inactive 7 latch_r_active 6 latch_l_inactive 5 latch_l_active Attention: Do not use soft stop in combination with stallGuard2. 1: Enable stop by stallGuard2. Disable to release motor after stop event. Attention: Do not enable during motor spin-up, wait until the motor velocity exceeds a certain value, where stallGuard2 delivers a stable result. Reserved, set to 0 1: Activates latching of the position to XLATCH upon an inactive going edge on the right reference switch input REFR. The active level is defined by pol_stop_r. 1: Activates latching of the position to XLATCH upon an active going edge on the right reference switch input REFR. Hint: Activate latch_r_active to detect any spurious stop event by reading status_latch_r. 1: Activates latching of the position to XLATCH upon an inactive going edge on the left reference switch input REFL. The active level is defined by pol_stop_l. 1: Activates latching of the position to XLATCH upon an active going edge on the left reference switch input REFL. 4 3 swap_lr pol_stop_r 2 pol_stop_l 1 stop_r_enable Hint: Activate latch_l_active to detect any spurious stop event by reading status_latch_l. 1: Swap the left and the right reference switch input Sets the active polarity of the right reference switch input (0=low active, 1=high active) Sets the active polarity of the left reference switch input (0=low active, 1=high active) 1: Enables automatic motor stop during active right reference switch input 0 stop_l_enable Hint: The motor restarts in case the stop switch becomes released. 1: Enables automatic motor stop during active left reference switch input Hint: The motor restarts in case the stop switch becomes released. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 23 6.2.2.2 RAMP_STAT – Ramp and Reference Switch Status Register 0X35, 0X55: RAMP_STAT – RAMP AND REFERENCE SWITCH STATUS REGISTER R/W R Bit 13 Name status_sg R+C 12 second_move R 11 R R 10 9 R 8 R+C 7 t_zerowait_ active vzero position_ reached velocity_ reached event_pos_ reached R+C 6 event_stop_ sg R 5 event_stop_r 4 event_stop_l 3 status_latch_r 2 status_latch_l 1 0 status_stop_r status_stop_l R+C R www.trinamic.com Comment 1: Signals an active stallGuard2 input from the coolStep driver, if enabled. Hint: When polling this flag, stall events may be missed – activate sg_stop to be sure not to miss the stall event. 1: Signals that the automatic ramp requires moving back in the opposite direction, e.g. due to on-the-fly parameter change (Flag is cleared upon reading) 1: Signals, that T_ZEROWAIT is active after a motor stop. During this time, the motor is in standstill. 1: Signals, that the actual velocity is 0. 1: Signals, that the target position is reached. This flag becomes set while X_ACTUAL and X_TARGET match. 1: Signals, that the target velocity is reached. This flag becomes set while V_ACTUAL and VMAX match. 1: Signals, that the target position has been reached (pos_reached becoming active). (Flag and interrupt condition are cleared upon reading) This bit is ORed to the interrupt output signal. 1: Signals an active StallGuard2 stop event. (Flag and interrupt condition are cleared upon reading) This bit is ORed to the interrupt output signal. 1: Signals an active stop right condition due to stop switch. The stop condition and the interrupt condition can be removed by setting RAMP_MODE to hold mode or by commanding a move to the opposite direction. In soft_stop mode, the condition will remain active until the motor has stopped motion into the direction of the stop switch. Disabling the stop switch or the stop function also clears the flag, but the motor will continue motion. This bit is ORed to the interrupt output signal. 1: Signals an active stop left condition due to stop switch. The stop condition and the interrupt condition can be removed by setting RAMP_MODE to hold mode or by commanding a move to the opposite direction. In soft_stop mode, the condition will remain active until the motor has stopped motion into the direction of the stop switch. Disabling the stop switch or the stop function also clears the flag, but the motor will continue motion. This bit is ORed to the interrupt output signal. 1: Latch right ready (enable position latching using SWITCH_MODE settings latch_r_active or latch_r_inactive) (Flag is cleared upon reading) 1: Latch left ready (enable position latching using SWITCH_MODE settings latch_l_active or latch_l_inactive) (Flag is cleared upon reading) Reference switch right status (1=active) Reference switch left status (1=active) TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 24 5.3 Motor Driver Registers MOTOR DRIVER REGISTER SET (MOTOR 1: 0X60…0X6F, MOTOR 2: 0X70…0X7F) R/W Addr n W 0x60 0x70 32 W W W 0x61 … 0x67 0x71 … 0x77 0x68 0x78 0x69 0x79 7 x 32 32 8 + 8 Register MSLUT1[0] MSLUT2[0] microstep table entries 0…31 MSLUT1[1...7] MSLUT2[1...7] microstep table entries 32…255 MSLUTSEL1 MSLUTSEL2 MSLUTSTART Description / bit names Each bit gives the difference between microstep x and x+1 when combined with the corresponding MSLUTSEL W bits: 0: W= %00: -1 %01: +0 %10: +1 %11: +2 1: W= %00: +0 %01: +1 %10: +2 %11: +3 This is the differential coding for the first quarter of a wave. Start values for CUR_A and CUR_B are stored for MSCNT position 0 in START_SIN and START_SIN90_120. ofs31, ofs30, …, ofs01, ofs00 … ofs255, ofs254, …, ofs225, ofs224 This register defines four segments within each quarter MSLUT wave. Four 2 bit entries determine the meaning of a 0 and a 1 bit in the corresponding segment of MSLUT. See separate table! bit 7… 0: START_SIN bit 23… 16: START_SIN90_120 START_SIN gives the absolute current at microstep table entry 0. START_SIN90_120 gives the absolute current for microstep table entry at positions 256. Start values are transferred to the microstep registers CUR_A and CUR_B, whenever the reference position MSCNT=0 is passed. R 0x6A 0x7A 10 MSCNT R 0x6B 0x7B 9 + 9 MSCURACT RW 0x6C 0x7C 32 CHOPCONF W 0x6D 0x7D 25 COOLCONF www.trinamic.com Microstep counter. Indicates actual position in the microstep table for CUR_A. CUR_B uses an offset of 256. Hint: Move to a position where MSCNT is zero before re-initializing MSLUTSTART or MSLUT and MSLUTSEL. bit 8… 0: CUR_A (signed): Actual microstep current for motor phase A as read from MSLUT (not scaled by current) bit 24… 16: CUR_B (signed): Actual microstep current for motor phase B as read from MSLUT (not scaled by current) chopper and driver configuration See separate table! coolStep smart current control register and stallGuard2 configuration See separate table! Range [Unit] 32x 0 or 1 reset default= sine wave table 7x 32x 0 or 1 reset default= sine wave table 0<X1<X2<X3 reset default= sine wave table START_SIN reset default =0 START_SIN90_1 20 reset default =247 TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 25 MOTOR DRIVER REGISTER SET (MOTOR 1: 0X60…0X6F, MOTOR 2: 0X70…0X7F) R/W Addr 0x6F 0x7F R n 32 Register DRV_ STATUS Description / bit names stallGuard2 value and driver error flags See separate table! Range [Unit] MIRCOSTEP TABLE CALCULATION FOR A SINE WAVE EQUIVALENT TO THE POWER ON DEFAULT: i:[0… 255] is the table index The amplitude of the wave is 248. The resulting maximum positive value is 247 and the maximum negative value is -248. The round function rounds values from 0.5 to 1.4999 to 1 - 5.3.1 MSLUTSEL – Look up Table Segmentation Definition 0X68, 0X78: MSLUTSEL – LOOK UP TABLE SEGMENTATION DEFINITION Bit 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Name X3 X2 Function LUT segment 3 start LUT segment 2 start Comment The sine wave look up table can be divided into up to four segments using an individual step width control entry Wx. The segment borders are selected by X1, X2 and X3. Segment Segment Segment Segment 0 1 2 3 goes goes goes goes from from from from 0 to X1-1. X1 to X2-1. X2 to X3-1. X3 to 255. For defined response the values shall satisfy: 0<X1<X2<X3 X1 LUT segment 1 start W3 LUT width select from ofs(X3) to ofs255 LUT width select from ofs(X2) to ofs(X3-1) LUT width select from ofs(X1) to ofs(X2-1) LUT width select from ofs00 to ofs(X1-1) W2 W1 W0 www.trinamic.com Width control bit coding W0…W3: %00: MSLUT entry 0, 1 select: -1, +0 %01: MSLUT entry 0, 1 select: +0, +1 %10: MSLUT entry 0, 1 select: +1, +2 %11: MSLUT entry 0, 1 select: +2, +3 TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 26 5.3.2 CHOPCONF – Chopper Configuration 0X6C, 0X7C: CHOPCONF – CHOPPER CONFIGURATION Bit 31 Name - Function reserved Comment set to 0 30 diss2g 29 - short to GND protection disable reserved 0: Short to GND protection is on 1: Short to GND protection is disabled set to 0 28 - reserved set to 0 27 - reserved set to 0 26 - reserved set to 0 25 - reserved set to 0 24 - reserved set to 0 23 sync3 22 sync2 21 sync1 SYNC PWM clock 20 sync0 19 vhighchm high velocity chopper mode 18 vhighfs high velocity fullstep selection 17 vsense 16 tbl1 15 tbl0 sense resistor voltage based current scaling TBL blank time select 14 chm chopper mode 13 rndtf random TOFF time 12 disfdcc fast decay mode 11 fd3 TFD [3] This register allows synchronization of the chopper for both phases of a two phase motor in order to avoid the occurrence of a beat, especially at low motor velocities. It is automatically switched off above VHIGH. %0000: Chopper sync function chopSync off %0001 … %1111: Synchronization with fSYNC = fCLK/(sync*64) Hint: Set TOFF to a low value, so that the chopper cycle is ended, before the next sync clock pulse occurs. Set for the double desired chopper frequency for chm=0, for the desired base chopper frequency for chm=1. This bit enables switching to chm=1 and fd=0, when VHIGH is exceeded. This way, a higher velocity can be achieved. Can be combined with vhighfs=1. If set, the TOFF setting automatically becomes doubled during high velocity operation in order to avoid doubling of the chopper frequency. This bit enables switching to fullstep, when VHIGH is exceeded. Switching takes place only at 45° position. The fullstep target current uses the current value from the microstep table at the 45° position. 0: Low sensitivity, high sense resistor voltage 1: High sensitivity, low sense resistor voltage %00 … %11: Set comparator blank time to 16, 24, 36 or 54 clocks Hint: %10 is recommended for most applications 0 Standard mode (spreadCycle) 1 Constant off time with fast decay time. Fast decay time is also terminated when the negative nominal current is reached. Fast decay is after on time. 0 Chopper off time is fixed as set by TOFF 1 Random mode, TOFF is random modulated by dNCLK= -12 … +3 clocks. chm=1: disfdcc=1 disables current comparator usage for termination of the fast decay cycle chm=1: MSB of fast decay time setting TFD www.trinamic.com synchronization TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 27 0X6C, 0X7C: CHOPCONF – CHOPPER CONFIGURATION Bit 10 Name hend3 9 hend2 8 hend1 7 hend0 Function HEND hysteresis low value OFFSET sine wave offset Comment chm=0 %0000 … %1111: Hysteresis is -3, -2, -1, 0, 1, …, 12 (1/512 of this setting adds to current setting) This is the hysteresis value which becomes used for the hysteresis chopper. chm=1 6 hstrt2 5 hstrt1 4 hstrt0 HSTRT hysteresis start value added to HEND TFD [2..0] fast decay time setting 3 toff3 2 toff2 1 toff1 0 toff0 www.trinamic.com TOFF off time and driver enable %0000 … %1111: Offset is -3, -2, -1, 0, 1, …, 12 This is the sine wave offset and 1/512 of the value becomes added to the absolute value of each sine wave entry. chm=0 %000 … %111: Add 1, 2, …, 8 to hysteresis low value HEND (1/512 of this setting adds to current setting) Attention: Effective HEND+HSTRT ≤ 16. Hint: Hysteresis decrement is done each 16 clocks chm=1 Fast decay time setting (MSB: fd3): %0000 … %1111: Fast decay time setting TFD with NCLK= 32*HSTRT (%0000: slow decay only) Off time setting controls duration of slow decay phase NCLK= 12 + 32*TOFF %0000: Driver disable, all bridges off %0001: 1 – use only with TBL ≥ 2 %0010 … %1111: 2 … 15 TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 28 5.3.3 COOLCONF – Smart Energy Control coolStep and stallGuard2 0X6D, 0X7D: COOLCONF – SMART ENERGY CONTROL COOLSTEP AND STALLGUARD2 Bit … 24 Name sfilt Function reserved stallGuard2 filter enable 23 22 21 20 19 18 17 16 15 sgt6 sgt5 sgt4 sgt3 sgt2 sgt1 sgt0 seimin reserved stallGuard2 threshold value 14 13 sedn1 sedn0 12 11 10 9 8 7 6 5 4 3 2 1 0 semax3 semax2 semax1 semax0 seup1 seup0 semin3 semin2 semin1 semin0 www.trinamic.com minimum current for smart current control current down step speed reserved stallGuard2 hysteresis value for smart current control reserved current up step width reserved minimum stallGuard2 value for smart current control and smart current enable Comment set to 0 0 Standard mode, high time resolution for stallGuard2 1 Filtered mode, stallGuard2 signal updated for each four fullsteps only to compensate for motor pole tolerances set to 0 This signed value controls stallGuard2 level for stall output and sets the optimum measurement range for readout. A lower value gives a higher sensitivity. Zero is the starting value working with most motors. -64 to +63: A higher value makes stallGuard2 less sensitive and requires more torque to indicate a stall. 0: 1/2 of current setting (IRUN) 1: 1/4 of current setting (IRUN) %00: For each 32 stallGuard2 values decrease by one %01: For each 8 stallGuard2 values decrease by one %10: For each 2 stallGuard2 values decrease by one %11: For each stallGuard2 value decrease by one set to 0 If the stallGuard2 result is equal to or above (SEMIN+SEMAX+1)*32, the motor current becomes decreased to save energy. %0000 … %1111: 0 … 15 set to 0 Current increment steps per measured stallGuard2 value %00 … %11: 1, 2, 4, 8 set to 0 If the stallGuard2 result falls below SEMIN*32, the motor current becomes increased to reduce motor load angle. %0000: smart current control coolStep off %0001 … %1111: 1 … 15 TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 29 5.3.4 DRV_STATUS – stallGuard2 Value and Driver Error Flags 0X6F, 0X7F: DRV_STATUS – STALLGUARD2 VALUE AND DRIVER ERROR FLAGS Bit 31 30 Name stst olb 29 ola 28 s2gb 27 s2ga 26 otpw 25 ot overtemperature flag 24 23 22 21 20 19 18 17 16 15 stallGuard - stallGuard2 status reserved 1: Overtemperature pre-warning threshold is exceeded. The overtemperature pre-warning flag is common for both drivers. 1: Overtemperature limit has been reached. Drivers become disabled until otpw is also cleared due to cooling down of the IC. The overtemperature flag is common for both drivers. 1: Motor stall detected (SG_RESULT=0) Ignore these bits CS ACTUAL actual motor current / smart energy current Actual current control scaling, for monitoring smart energy current scaling controlled via settings in register COOLCONF. fsactive 1: Indicates that the driver has switched to fullstep as defined by chopper mode settings and velocity thresholds. 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 - full step active indicator reserved stallGuard2 result respectively PWM on time for coil A in stand still for motor temperature detection Mechanical load measurement: The stallGuard2 result gives a means to measure mechanical motor load. A higher value means lower mechanical load. A value of 0 signals highest load. With optimum SGT setting, this is an indicator for a motor stall. The stall detection compares SG_RESULT to 0 in order to detect a stall. SG_RESULT is used as a base for coolStep operation, by comparing it to a programmable upper and a lower limit. SG_ RESULT www.trinamic.com Function standstill indicator open load indicator phase B open load indicator phase A short to ground indicator phase B short to ground indicator phase A overtemperature prewarning flag Comment This flag indicates motor stand still in each operation mode. 1: Open load detected on phase A or B. Hint: This is just an informative flag. The driver takes no action upon it. False detection may occur in fast motion and standstill. Check during slow motion, only. 1: Short to GND detected on phase A or B. The driver becomes disabled. The flags stay active, until the driver is disabled by software or by the ENN input. Ignore these bits Temperature measurement: In standstill, no stallGuard2 result can be obtained. SG_RESULT shows the chopper on-time for motor coil A instead. If the motor is moved to a determined microstep position at a certain current setting, a comparison of the chopper on-time can help to get a rough estimation of motor temperature. As the motor heats up, its coil resistance rises and the chopper on-time increases. TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 30 6 Current Setting The internal 5 V supply voltage available at the pin 5VOUT is used as a reference for the coil current regulation based on the sense resistor voltage measurement. The desired maximum motor current is set by selecting an appropriate value for the sense resistor. The sense resistor voltage range can be selected by the vsense bit in CHOPCONF. The low sensitivity setting (high sense resistor voltage, vsense=0) brings best and most robust current regulation, while high sensitivity (low sense resistor voltage, vsense=1) reduces power dissipation in the sense resistor. The high sensitivity setting reduces the power dissipation in the sense resistor by nearly half. After choosing the vsense setting and selecting the sense resistor, the currents to both coils are scaled by the 5-bit current scale parameters (IHOLD, IRUN). The sense resistor value is chosen so that the maximum desired current (or slightly more) flows at the maximum current setting (IRUN = %11111). Using the internal sine wave table, which has the amplitude of 248, the RMS motor current can be calculated by: The momentary motor current is calculated by: CS is the current scale setting as set by the IHOLD and IRUN and coolStep. VFS is the full scale voltage as determined by vsense control bit (please refer to electrical characteristics, VSRTL and VSRTH). CURA/B is the actual value from the internal sine wave table. Parameter IRUN IHOLD IHOLD DELAY vsense Description Current scale when motor is running. Scales coil current values as taken from the internal sine wave table. For high precision motor operation, work with a current scaling factor in the range 16 to 31, because scaling down the current values reduces the effective microstep resolution by making microsteps coarser. This setting also controls the maximum current value set by coolStep. Identical to IRUN, but for motor in stand still. Allows smooth current reduction from run current to hold current. IHOLDDELAY controls the number of clock cycles for motor power down after T_ZEROWAIT in increments of 2^18 clocks: 0=instant power down, 1..15: Current reduction delay per current step in multiple of 2^18 clocks. Setting 0 … 31 Comment scaling factor 1/32, 2/32, … 32/32 0 1 …15 instant IHOLD 1*218 … 15*218 clocks per current decrement Example: When using IRUN=31 and IHOLD=16, 15 current steps are required for hold current reduction. A IHOLDDELAY setting of 4 thus results in a power down time of 4*15*2^18 clock cycles, i.e. roughly one second at 16MHz. Allows control of the sense resistor voltage range 0 for full scale current. 1 www.trinamic.com 0.32 V 0.18 V TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 31 6.1 Sense Resistors Sense resistors should be carefully selected. The full motor current flows through the sense resistors. They also see the switching spikes from the MOSFET bridges. A low-inductance type such as film or composition resistors is required to prevent spikes causing ringing on the sense voltage inputs leading to unstable measurement results. A low-inductance, low-resistance PCB layout is essential. Any common GND path for the two sense resistors must be avoided, because this would lead to coupling between the two current sense signals. A massive ground plane is best. Please also refer to layout considerations in chapter 15.3. The sense resistor needs to be able to conduct the peak motor coil current in motor standstill conditions, unless standby power is reduced. Under normal conditions, the sense resistor sees a bit less than the coil RMS current, because no current flows through the sense resistor during the slow decay phases. The peak sense resistor power dissipation is: For high current applications, power dissipation is halved by using the low vsense setting and using an adapted resistance value. Please be aware, that in this case any voltage drop in PCB traces has a larger influence on the result. A compact layout with massive ground plane is best to avoid parasitic resistance effects. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 32 7 Chopper Operation The currents through both motor coils are controlled using choppers. The choppers work independently of each other. In Figure 7.1 the different chopper phases are shown. +VM +VM +VM ICOIL ICOIL ICOIL RSENSE On Phase: current flows in direction of target current RSENSE Fast Decay Phase: current flows in opposite direction of target current RSENSE Slow Decay Phase: current re-circulation Figure 7.1 Chopper phases Although the current could be regulated using only on phases and fast decay phases, insertion of the slow decay phase is important to reduce electrical losses and current ripple in the motor. The duration of the slow decay phase is specified in a control parameter and sets an upper limit on the chopper frequency. The current comparator can measure coil current during phases when the current flows through the sense resistor, but not during the slow decay phase, so the slow decay phase is terminated by a timer. The on phase is terminated by the comparator when the current through the coil reaches the target current. The fast decay phase may be terminated by either the comparator or another timer. When the coil current is switched, spikes at the sense resistors occur due to charging and discharging parasitic capacitances. During this time, typically one or two microseconds, the current cannot be measured. Blanking is the time when the input to the comparator is masked to block these spikes. There are two chopper modes available: a new high-performance chopper algorithm called spreadCycle and a proven constant off-time chopper mode. The constant off-time mode cycles through three phases: on, fast decay, and slow decay. The spreadCycle mode cycles through four phases: on, slow decay, fast decay, and a second slow decay. The chopper frequency is an important parameter for a chopped motor driver. A too low frequency might generate audible noise. A higher frequency reduces current ripple in the motor, but with a too high frequency magnetic losses may rise. Also power dissipation in the driver rises with increasing frequency due to the increased influence of switching slopes causing dynamic dissipation. Therefore, a compromise needs to be found. Most motors are optimally working in a frequency range of 20 kHz to 40 kHz. The chopper frequency is influenced by a number of parameter settings as well as by the motor inductivity and supply voltage. A chopper frequency in the range of 20 kHz to 40 kHz gives a good result for most motors. A higher frequency leads to increased switching losses. It is advised to check the resulting frequency and to work below 50 kHz. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 33 Three parameters are used for controlling both chopper modes: Parameter TOFF Description Setting Sets the slow decay time (off time). This setting also 0 limits the maximum chopper frequency. 1…15 0 Comment chopper off off time setting NCLK= 12 + 32*TOFF (1 will work with minimum blank time of 24 clocks) 16 tCLK 1 24 tCLK 2 36 tCLK 3 54 tCLK 0 1 spreadCycle classic const. off time Setting this parameter to zero completely disables all driver transistors and the motor can free-wheel. TBL chm Selects the comparator blank time. This time needs to safely cover the switching event and the duration of the ringing on the sense resistor. For most applications, a setting of 1 or 2 is good. For highly capacitive loads, e.g. when filter networks are used, a setting of 2 or 3 will be required. Selection of the chopper mode www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 34 7.1 spreadCycle 2-Phase Motor Chopper The spreadCycle (pat. fil.) chopper algorithm is a precise and simple to use chopper mode which automatically determines the optimum length for the fast-decay phase. Several parameters are available to optimize the chopper to the application. Each chopper cycle is comprised of an on phase, a slow decay phase, a fast decay phase and a second slow decay phase (see Figure 7.2). The slow decay phases limit the maximum chopper frequency and are important for low motor and driver power dissipation. The hysteresis start setting limits the chopper frequency by forcing the driver to introduce a minimum amount of current ripple into the motor coils. The motor inductance limits the ability of the chopper to follow a changing motor current. The duration of the on phase and the fast decay phase must be longer than the blanking time, because the current comparator is disabled during blanking. This requirement is satisfied by choosing a positive value for the hysteresis as can be estimated by the following calculation: Where: dICOILBLANK is the coil current change during the blanking time dICOILSD is the coil current change during the slow decay time tSD is the slow decay time tBLANK is the blank time (as set by TBL), VM is the motor supply voltage, ICOIL is the peak motor coil current at the maximum motor current setting CS, RCOIL and LCOIL are motor coil inductivity and motor coil resistance. With this, a lower limit for the start hysteresis setting can be determined: Example: For a 42mm stepper motor with 7.5 mH, 4.5 Ω phase and 1 A RMS current at IRUN=31, i.e. 1.41 A peak current, at 24 V with a blank time of 1.5 µs: With this, the minimum hysteresis start setting is 5.2. A value in the range 6 to 10 can be used. An Excel calculation spreadsheet is provided for the ease of use. As experiments show, the setting is quite independent of the motor, because higher current motors typically also have a lower coil resistance. Choosing a medium default value for the hysteresis (for example, effective HSTART+HEND=10) normally fits most applications. The setting can be optimized by experimenting with the motor: A too low setting will result in reduced microstep accuracy, while a too high setting will lead to more chopper noise and motor power dissipation. When measuring the sense resistor voltage in motor standstill at a medium coil current with an oscilloscope, a too low setting shows a fast decay phase not longer than the blanking time. When the fast decay time www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 35 becomes slightly longer than the blanking time, the setting is optimum. You can reduce the off-time setting, if this is hard to reach. The hysteresis principle could in some cases lead to the chopper frequency becoming too low, e.g. when the coil resistance is high when compared to the supply voltage. This is avoided by splitting the hysteresis setting into a start setting (HSTRT+HEND) and an end setting (HEND). An automatic hysteresis decrementer (HDEC) interpolates between both settings, by decrementing the hysteresis value stepwise each 16 system clocks. At the beginning of each chopper cycle, the hysteresis begins with a value which is the sum of the start and the end values (HSTRT+HEND), and decrements during the cycle, until either the chopper cycle ends or the hysteresis end value (HEND) is reached. This way, the chopper frequency is stabilized at high amplitudes and low supply voltage situations, if the frequency gets too low. This avoids the frequency reaching the audible range. I target current + hysteresis start HDEC target current + hysteresis end target current target current - hysteresis end target current - hysteresis start on sd fd sd t Figure 7.2 spreadCycle chopper scheme showing coil current during a chopper cycle Two parameters control spreadCycle mode: Parameter HSTRT HEND Description Setting Hysteresis start setting. This value is an offset 0…7 from the hysteresis end value HEND. Comment HSTRT=1…8 Hysteresis end setting. Sets the hysteresis end 0…2 value after a number of decrements. The sum HSTRT+HEND must be ≤16. At a current setting of 3 max. 30 (amplitude reduced to 240), the sum is 4…15 not limited. -3…-1: negative HEND This value adds to HEND. 0: zero HEND 1…12: positive HEND Example: In the example above a hysteresis start of 7 has been chosen. You might decide to not use hysteresis decrement. In this case set: HEND=10 HSTRT=0 (sets an effective end value of 7) (sets minimum hysteresis) In order to take advantage of the variable hysteresis, we can set hysteresis end to about half of the start value, e.g. 4. The resulting configuration register values are as follows: HEND=7 HSTRT=2 www.trinamic.com (sets an effective end value of 4) (sets an effective start value of hysteresis end +3) TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 36 7.2 Classic 2-Phase Motor Constant Off Time Chopper The classic constant off-time chopper uses a fixed-time fast decay following each on phase. While the duration of the on phase is determined by the chopper comparator, the fast decay time needs to be long enough for the driver to follow the falling slope of the sine wave, but it should not be so long that it causes excess motor current ripple and power dissipation. This can be tuned using an oscilloscope or evaluating motor smoothness at different velocities. A good starting value is a fast decay time setting similar to the slow decay time setting. I target current + offset mean value = target current on fd on sd fd sd t Figure 7.3 Classic const. off time chopper with offset showing coil current After tuning the fast decay time, the offset should be tuned for a smooth zero crossing. This is necessary because the fast decay phase makes the absolute value of the motor current lower than the target current (see Figure 7.4). If the zero offset is too low, the motor stands still for a short moment during current zero crossing. If it is set too high, it makes a larger microstep. Typically, a positive offset setting is required for smoothest operation. Target current I Target current I Coil current Coil current t Coil current does not have optimum shape t Target current corrected for optimum shape of coil current Figure 7.4 Zero crossing with classic chopper and correction using sine wave offset Three parameters control constant off-time mode: Parameter TFD (fd3 & HSTRT) Description Setting Fast decay time setting. With CHM=1, these bits 0 control the portion of fast decay for each chopper 1…15 cycle. Comment slow decay only duration of fast decay phase OFFSET (HEND) Sine wave offset. With CHM=1, these bits control 0…2 the sine wave offset. A positive offset corrects for 3 zero crossing error. 4…15 negative offset: -3…-1 Selects usage of the current comparator for 0 termination of the fast decay cycle. If current comparator is enabled, it terminates the fast decay cycle in case the current reaches a higher negative 1 value than the actual positive value. enable comparator termination of fast decay cycle disfdcc www.trinamic.com no offset: 0 positive offset 1…12 end by time only TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 37 7.3 Random Off Time In the constant off-time chopper mode, both coil choppers run freely without synchronization. The frequency of each chopper mainly depends on the coil current and the motor coil inductance. The inductance varies with the microstep position. With some motors, a slightly audible beat can occur between the chopper frequencies when they are close together. This typically occurs at a few microstep positions within each quarter wave. This effect is usually not audible when compared to mechanical noise generated by ball bearings, etc. Another factor which can cause a similar effect is a poor layout of the sense resistor GND connections. A common factor, which can cause motor noise, is a bad PCB layout causing coupling of both sense resistor voltages (please refer layouts hint in chapter 15.3). To minimize the effect of a beat between both chopper frequencies, an internal random generator is provided. It modulates the slow decay time setting when switched on by the rndtf bit. The rndtf feature further spreads the chopper spectrum, reducing electromagnetic emission on single frequencies. Parameter rndtf Description Setting This bit switches on a random off time generator, 0 which slightly modulates the off time TOFF using 1 a random polynomial. www.trinamic.com Comment disable random modulation enable TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 38 7.4 chopSync2 for Quiet Motors While a frequency adaptive chopper like spreadCycle provides excellent high velocity operation, in some applications, a constant frequency chopper is preferred rather than a frequency adaptive chopper. This may be due to chopper noise in motor standstill, or due to electro-magnetic emission. chopSync provides a means to synchronize the choppers for both coils with a common clock, by extending the off time of the coils. It integrates with both chopper principles. However, a careful set up of the chopper is necessary, because chopSync2 can just increment the off times, but not reduce the duration of the chopper cycles themselves. Therefore, it is necessary to test successful operation best with an oscilloscope. Set up the chopper as detailed above, but take care to have chopper frequency higher than the chopSync2 frequency. As high motor velocities take advantage of the normal, adaptive chopper style, chopSync2 becomes automatically switched off using the VHIGH velocity limit programmed within the motion controller. A suitable chopSync2 SYNC value can be calculated as follows: Example: The motor is operated in spreadCycle mode (chm=0). The minimum chopper frequency for standstill and slow motion (up to VHIGH) has been determined to be 25 kHz under worst case operation conditions (hot motor, low supply voltage). The standstill noise needs to be minimized by using chopSync. The IC uses an external 16 MHz clock. Considering the chopper mode 0, SYNC has to be set for the closest value resulting in or below the double frequency, e.g. 50 kHz. Using above formula, a value of 5 results exactly and can be used. Trying a value of 6, a frequency of 41.7 kHz results, which still gives an effective chopper frequency of slightly above 20 kHz, and thus would also be a valid solution. A value of 7 might still be good, but could already give high frequency noise. In chopper mode 1, SYNC could be set to any value between 10 and 13 to be within the chopper frequency range of 19.8 kHz to 25 kHz. Parameter SYNC Description Setting This register allows synchronization of the 0 chopper for both phases of a two phase motor in order to avoid the occurrence of a beat, especially 1…15 at low motor velocities. It is automatically switched off above VHIGH. Hint: Set TOFF to a low value, so that the chopper cycle is ended, before the next sync clock pulse occurs. Set SYNC for the double desired chopper frequency for chm=0, for the desired base chopper frequency for chm=1. www.trinamic.com Comment chopSync off fCLK/64 … fCLK/(15*64) TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 39 8 Driver Diagnostic Flags The TMC5031 drivers supply a complete set of diagnostic and protection capabilities, like short to GND protection and undervoltage detection. A detection of an open load condition allows testing if a motor coil connection is interrupted. See the DRV_STATUS table for details. 8.1 Temperature Measurement The TMC5031 integrates a two level temperature sensor (120°C prewarning and 150°C thermal shutdown) for diagnostics and for protection of the IC against excess heat. The heat is mainly generated by the voltage regulator and the motor driver stages. The central temperature detector can detect heat accumulation on the chip, i.e. due to missing convection cooling or rising environment temperature. It cannot detect overheating of the power transistors in all cases, e.g. with bad PCB layout, because heat transfer between power transistors and temperature sensor depends on the PCB layout and environmental conditions. Most critical situations, where the driver MOSFETs could be overheated, are avoided when enabling the short to GND protection. For many applications, the overtemperature prewarning will indicate an abnormal operation situation and can be used to initiate user warning or power reduction measures like motor current reduction. If continuous operation in hot environments is necessary, a more precise processor based temperature measurement should be used to realize application specific overtemperature detection. The thermal shutdown is just an emergency measure and temperature rising to the shutdown level should be prevented by design. After triggering the overtemperature sensor (ot flag), the driver remains switched off until the system temperature falls below the prewarning level (otpw) to avoid continuous heating to the shut down level. 8.2 Short to GND Protection The TMC5031 power stages are protected against a short circuit condition by an additional measurement of the current flowing through the highside MOSFETs. This is important, as most short circuit conditions result from a motor cable insulation defect, e.g. when touching the conducting parts connected to the system ground. The short detection is protected against spurious triggering, e.g. by ESD discharges, by retrying three times before switching off the motor. Once a short condition is safely detected, the corresponding driver bridge becomes switched off, and the s2ga or s2gb flag becomes set. In order to restart the motor, the user must intervene by disabling and re-enabling the driver. It should be noted, that the short to GND protection cannot protect the system and the power stages for all possible short events, as a short event is rather undefined and a complex network of external components may be involved. Therefore, short circuits should basically be avoided. 8.3 Open Load Diagnostics Interrupted cables are a common cause for systems failing, e.g. when connectors are not firmly plugged. The TMC5031 detects open load conditions by checking, if it can reach the desired motor coil current. This way, also undervoltage conditions, high motor velocity settings or short and overtemperature conditions may cause triggering of the open load flag, and inform the user, that motor torque may suffer. In motor stand still, open load cannot be measured, as the coils might eventually have zero current. In order to safely detect an interrupted coil connection, read out the open load flags at low or nominal motor velocity operation, only. However, the ola and olb flags have just informative character and do not cause any action of the driver. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 40 9 Ramp Generator The TMC5031 integrates a new type of ramp generator, which offers faster machine operation compared to the classical linear acceleration ramps. The sixPoint ramp generator allows adapting the acceleration ramps to the torque curves of a stepper motor and uses two different acceleration settings each for the acceleration phase and for the deceleration phase. See Figure 9.2. 9.1 Real World Unit Conversion The TMC5031 uses its internal or external clock signal as a time reference for all internal operations. Thus, all time, velocity and acceleration settings are referenced to fCLK. For best stability and reproducibility, it is recommended to use an external quartz oscillator as a time base, or to provide a clock signal from a microcontroller. The units of a TMC5031 register content are written as register[5031]. PARAMETER VS. UNITS Parameter / Symbol fCLK[Hz] s US FS µstep velocity v[Hz] µstep acceleration a[Hz/s] Unit [Hz] [s] µstep fullstep µsteps / s µsteps / s^2 USC microstep count counts rotations per second v[rps] rotations / s rps acceleration a[rps/s^2] rotations / s^2 ramp steps[µsteps] = rs µsteps calculation / description / comment clock frequency of the TMC5031 in [Hz] second v[Hz] = v[5031] * ( fCLK[Hz]/2 / 2^23 ) a[Hz/s] = a[5031] * fCLK[Hz]^2 / (512*256) / 2^24 microstep resolution in number of microsteps (i.e. the number of microsteps between two fullsteps – normally 256) v[rps] = v[µsteps/s] / USC / FSC FSC: motor fullsteps per rotation, e.g. 200 a[rps/s^2] = a[µsteps/s^2] / USC / FSC rs = (v[5031])^2 / a[5031] / 2^8 microsteps during linear acceleration ramp (assuming acceleration from 0 to v) 9.2 Ramp Generator Functionality For the ramp generator register set, please refer to the chapter 5.2. 9.2.1 Ramp Mode The ramp generator delivers two phase acceleration and two phase deceleration ramps with additional programmable start and stop velocities (see Figure 9.1). Note! The start velocity can be set to zero, if not used. The stop velocity can be set to one, if not used. Take care to always set VSTOP identical to or above VSTART. This ensures that even a short motion can be terminated successfully at the target position. The two different sets of acceleration and deceleration can be combined freely. A common transition speed V1 allows for velocity dependent switching between both acceleration and deceleration settings. A typical use case will use lower acceleration and deceleration values at higher velocities, as the motors torque declines at higher velocity. When considering friction in the system, it becomes clear, that typically deceleration of the system is quicker than acceleration. Thus, deceleration values can be higher in many applications. This way, operation speed of the motor in time critical applications can be maximized. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 41 As target positions and ramp parameters may be changed any time during the motion, the motion controller will always use the optimum (fastest) way to reach the target, while sticking to the constraints set by the user. This way it might happen, that the motion becomes automatically stopped, crosses zero and drives back again. This case is flagged by the special flag second_move. 9.2.2 Start and Stop Velocity When using increased levels of start- and stop velocity, it becomes clear, that a subsequent move into the opposite direction would provide a jerk identical to VSTART+VSTOP, rather than only VSTART. As the motor probably is not able to follow this, you can set a time delay for a subsequent move by setting TZEROWAIT. An active delay time is flagged by the flag t_zerowait_active. Once the target position is reached, the flag pos_reached becomes active. motor stop v acceleration phase acceleration phase deceleration phase VMAX DM AX AX AM V1 A1 D1 VSTOP VSTART 0 VACTUAL 1 -A TZEROWAIT t Figure 9.1 Ramp generator velocity trace showing consequent move in negative direction torque high deceleration 2xMFRICT MNOM2 Torque for VSTART MNOM1 high acceleration Torque available for acceleration A1 VMAX Torque required for static loads V1 0 reduced accel. Torque available for AMAX VSTART MFRICT reduced decel. motor torque MMAX velocity [RPM] MFRICT Portion of torque required for friction and static load within the system MMAX Motor pull-out torque at v=0 MNOM1/2 Torque available at V1 resp. VMAX Motor torque used in acceleration phase Overall torque usable for deceleration Figure 9.2 Illustration of optimized motor torque usage with TMC5031 ramp generator www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 42 9.2.3 Velocity Mode For the ease of use, velocity mode movements do not use the different acceleration and deceleration settings. You need to set VMAX and AMAX only for velocity mode. The ramp generator always uses AMAX to accelerate or decelerate to VMAX in this mode. In order to decelerate the motor to stand still, it is sufficient to set VMAX to zero. The flag vzero signals standstill of the motor. The flag velocity_reached always signals, that the target velocity has been reached. 9.3 Velocity Thresholds The ramp generator provides a number of velocity thresholds coupled to the actual velocity VACTUAL. The different ranges allow programming the motor to the optimum step mode, coil current and acceleration settings. motor going to standby motor in standby motor stand still microstepping coolStep + DM AX microstep coolStep + A1 microstep VSTOP VSTART 0 AX AM D1 VCOOLTHRS microstepping V1 motor in standby VMAX VHIGH high velocity fullstep v t RMS current coolStep current reduction dI * IHOLDDELAY VACTUAL TZEROWAIT current I_RUN I_HOLD Figure 9.3 Ramp generator velocity dependent motor control Since it is not necessary to differentiate the velocity to the last detail, the velocity thresholds use a reduced number of bits for comparison and the lower eight bits of the compare values become ignored. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 43 9.4 Reference Switches Prior to normal operation of the drive an absolute reference position must be set. The reference position can be found using a mechanical stop which can be detected by stall detection, or by a reference switch. In case of a linear drive, the mechanical motion range must not be left. This can be ensured by enabling the stop switch functions for the left and the right reference switch. Therefore, the ramp generator responds to a number of stop events as configured in the SW_MODE register. There are two ways to stop the motor: - it can be stopped abruptly, when a switch is hit. This is useful in an emergency case. - Or the motor can be softly decelerated to zero using deceleration settings. Note: Latching of the ramp position XACTUAL to the holding register XLATCH upon a switch event gives a precise snapshot of the position of the reference switch. REF_L +VCC_IO +VCC_IO 10k 10k 22k REF_R Motor 1nF Negative direction Optional RC filter (example) Positive direction Traveler Figure 9.4 Using reference switches (example) Normally open or normally closed switches can be used by programming the switch polarity or selecting the pull-up or pull-down resistor configuration. A normally closed switch is failsafe with respect to an interrupt of the switch connection. Switches which can be used are: - mechanical switches, - photo interrupters, or - hall sensors. Be careful to select resistors matching your switch requirements! In case of long cables additional RC filtering might be required near the TMC5031 reference inputs. Adding an RC filter will also reduce the danger of destroying the logic level inputs by wiring faults, but it will add a certain delay which should be considered with respect to the application. IMPLEMENTING A HOMING PROCEDURE - - Make sure, that the switch is not pressed. Activate position latching upon the desired switch event and activate motor (soft) stop upon active switch. Start a motion ramp into the direction of the switch. (Move to a more negative position for a left switch, to a more positive position for a right switch). You may timeout this motion by using a position ramping command. As soon as the switch is hit, the position becomes latched and the motor is stopped. Wait until the motor is in standstill again. Switch the ramp generator to hold mode and calculate the difference between the latched position and the actual position. Write the calculated difference into the actual position register. Now, the homing is finished. A move to position 0 will bring back the motor exactly to the switching point. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 44 10 stallGuard2 Load Measurement stallGuard2 provides an accurate measurement of the load on the motor. It can be used for stall detection as well as other uses at loads below those which stall the motor, such as coolStep loadadaptive current reduction. The stallGuard2 measurement value changes linearly over a wide range of load, velocity, and current settings, as shown in Figure 10.1. At maximum motor load, the value goes to zero or near to zero. This corresponds to a load angle of 90° between the magnetic field of the coils and magnets in the rotor. This also is the most energy-efficient point of operation for the motor. 1000 stallGuard2 reading 900 Start value depends on motor and operating conditions 800 700 600 stallGuard value reaches zero and indicates danger of stall. This point is set by stallGuard threshold value SGT. 500 400 Motor stalls above this point. Load angle exceeds 90° and available torque sinks. 300 200 100 0 10 20 30 40 50 60 70 80 90 100 motor load (% max. torque) Figure 10.1 Function principle of stallGuard2 Parameter SGT sfilt Status word SG Description This signed value controls the stallGuard2 threshold level for stall detection and sets the optimum measurement range for readout. A lower value gives a higher sensitivity. Zero is the starting value working with most motors. A higher value makes stallGuard2 less sensitive and requires more torque to indicate a stall. Enables the stallGuard2 filter for more precision of the measurement. If set, reduces the measurement frequency to one measurement per electrical period of the motor (4 fullsteps). Description Setting 0 Comment indifferent value +1… +63 -1… -64 less sensitivity higher sensitivity 0 1 standard mode filtered mode Range Comment This is the stallGuard2 result. A higher reading indicates less mechanical load. A lower reading indicates a higher load and thus a higher load angle. Tune the SGT setting to show a SG reading of roughly 0 to 100 at maximum load before motor stall. 0… 1023 0: highest load low value: high load high value: less load In order to use stallGuard2 and coolStep, the stallGuard2 sensitivity should first be tuned using the SGT setting! www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 45 10.1 Tuning the stallGuard2 Threshold SGT The stallGuard2 value SG is affected by motor-specific characteristics and application-specific demands on load and velocity. Therefore the easiest way to tune the stallGuard2 threshold SGT for a specific motor type and operating conditions is interactive tuning in the actual application. The procedure is: 1. Operate the motor at the normal operation velocity for your application and monitor SG. 2. Apply slowly increasing mechanical load to the motor. If the motor stalls before SG reaches zero, decrease SGT. If SG reaches zero before the motor stalls, increase SGT. A good SGT starting value is zero. SGT is signed, so it can have negative or positive values. 3. Now enable sg_stop and make sure, that the motor is safely stopped whenever it is stalled. Increase SGT if the motor becomes stopped before a stall occurs. 4. The optimum setting is reached when SG is between 0 and roughly 100 at increasing load shortly before the motor stalls, and SG increases by 100 or more without load. SGT in most cases can be tuned for a certain motion velocity or a velocity range. Make sure, that the setting works reliable in a certain range (e.g. 80% to 120% of desired velocity) and also under extreme motor conditions (lowest and highest applicable temperature). SG goes to zero when the motor stalls and the ramp generator can be programmed to stop the motor upon a stall event by enabling sg_stop in SW_MODE. The system clock frequency affects SG. An external crystal-stabilized clock should be used for applications that demand the highest performance. The power supply voltage also affects SG, so tighter regulation results in more accurate values. SG measurement has a high resolution, and there are a few ways to enhance its accuracy, as described in the following sections. Note! Application Note 002 Parameterization of stallGuard2 & coolStep is available on www.trinamic.com. 10.1.1 Variable Velocity Operation The SGT setting chosen as a result of the previously described SGT tuning (chapter 0) can be used for a certain velocity range. Outside this range, a stall may not be detected safely, and coolStep might not give the optimum result. stallGuard2 reading at no load optimum SGT setting 1000 20 900 18 800 16 700 14 600 12 500 10 400 8 300 6 200 4 100 2 0 0 good operation range with single SGT setting 50 lower limit for stall detection 100 150 200 250 300 back EMF reaches supply voltage 350 400 450 500 550 600 Motor RPM (200 FS motor) Figure 10.2 Example: Optimum SGT setting and stallGuard2 reading with an example motor In many applications, operation at or near a single operation point is used most of the time and a single setting is sufficient. The ramp generator provides a lower and an upper velocity threshold to match this. The stall detection should be ignored and disabled by software outside the determined operation point, e.g. during acceleration phases preceding a sensorless homing procedure. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 46 In some applications, a velocity dependent tuning of the SGT value can be expedient, using a small number of support points and linear interpolation. 10.1.2 Small Motors with High Torque Ripple and Resonance Motors with a high detent torque show an increased variation of the stallGuard2 measurement value SG with varying motor currents, especially at low currents. For these motors, the current dependency should be checked for best result. 10.1.3 Temperature Dependence of Motor Coil Resistance Motors working over a wide temperature range may require temperature correction, because motor coil resistance increases with rising temperature. This can be corrected as a linear reduction of SG at increasing temperature, as motor efficiency is reduced. 10.1.4 Accuracy and Reproducibility of stallGuard2 Measurement In a production environment, it may be desirable to use a fixed SGT value within an application for one motor type. Most of the unit-to-unit variation in stallGuard2 measurements results from manufacturing tolerances in motor construction. The measurement error of stallGuard2 – provided that all other parameters remain stable – can be as low as: 10.2 stallGuard2 Measurement Frequency and Filtering The stallGuard2 measurement value SG is updated with each full step of the motor. This is enough to safely detect a stall, because a stall always means the loss of four full steps. In a practical application, especially when using coolStep, a more precise measurement might be more important than an update for each fullstep because the mechanical load never changes instantaneously from one step to the next. For these applications, the sfilt bit enables a filtering function over four load measurements. The filter should always be enabled when high-precision measurement is required. It compensates for variations in motor construction, for example due to misalignment of the phase A to phase B magnets. The filter should only be disabled when rapid response to increasing load is required, such as for stall detection at high velocity. 10.3 Detecting a Motor Stall To safely detect a motor stall the stall threshold must be determined using a specific SGT setting. Therefore, you need to determine the maximum load the motor can drive without stalling and to monitor the SG value at this load, e.g. some value within the range 0 to 100. The stall threshold should be a value safely within the operating limits, to allow for parameter stray. The response at an SGT setting at or near 0 gives some idea on the quality of the signal: Check the SG value without load and with maximum load. They should show a difference of at least 100 or a few 100, which shall be large compared to the offset. If you set the SGT value in a way, that a reading of 0 occurs at maximum motor load, the stall can be automatically detected by the motion controller to issue a motor stop. 10.4 Limits of stallGuard2 Operation stallGuard2 does not operate reliably at extreme motor velocities: Very low motor velocities (for many motors, less than one revolution per second) generate a low back EMF and make the measurement unstable and dependent on environment conditions (temperature, etc.). Other conditions will also lead to extreme settings of SGT and poor response of the measurement value SG to the motor load. Very high motor velocities, in which the full sinusoidal current is not driven into the motor coils also leads to poor response. These velocities are typically characterized by the motor back EMF reaching the supply voltage. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 47 11 coolStep Operation coolStep is an automatic smart energy optimization for stepper motors based on the motor mechanical load, making them “green”. 11.1 User Benefits Energy efficiency Motor generates less heat Less cooling infrastructure Cheaper motor – – – – consumption decreased up to 75% improved mechanical precision for motor and driver does the job! coolStep allows substantial energy savings, especially for motors which see varying loads or operate at a high duty cycle. Because a stepper motor application needs to work with a torque reserve of 30% to 50%, even a constant-load application allows significant energy savings because coolStep automatically enables torque reserve when required. Reducing power consumption keeps the system cooler, increases motor life, and allows reducing cost in the power supply and cooling components. Reducing motor current by half results in reducing power by a factor of four. 11.2 Setting up for coolStep coolStep is controlled by several parameters, but two are critical for understanding how it works: Parameter Description SEMIN 4-bit unsigned integer that sets a lower threshold. 0 If SG goes below this threshold, coolStep 1…15 increases the current to both coils. The 4-bit SEMIN value is scaled by 32 to cover the lower half of the range of the 10-bit SG value. (The name of this parameter is derived from smartEnergy, which is an earlier name for coolStep.) 4-bit unsigned integer that controls an upper 0…15 threshold. If SG is sampled equal to or above this threshold enough times, coolStep decreases the current to both coils. The upper threshold is (SEMIN + SEMAX + 1)*32. SEMAX Range Comment disable coolStep threshold is SEMIN*32 threshold is (SEMIN+SEMAX+1)*32 FIGURE 11.1 SHOWS THE OPERATING REGIONS OF COOLSTEP: - The black line represents the SG measurement value. The blue line represents the mechanical load applied to the motor. The red line represents the current into the motor coils. When the load increases, SG falls below SEMIN, and coolStep increases the current. When the load decreases, SG rises above (SEMIN + SEMAX + 1) * 32, and the current is reduced. www.trinamic.com stallGuard2 reading mechanical load 48 motor current TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) current setting I_RUN (upper limit) motor current reduction area SEMAX+SEMIN+1 SEMIN ½ or ¼ I_RUN (lower limit) motor current increment area 0=maximum load load angle optimized Zeit slow current reduction due to reduced motor load load angle optimized current increment due to increased load stall possible load angle optimized Figure 11.1 coolStep adapts motor current to the load Five more parameters control coolStep and one status value is returned: Parameter SEUP SEDN SEIMIN VCOOL THRS VHIGH Status word CSACTUAL Description Range Sets the current increment step. The current 0…3 becomes incremented for each measured stallGuard2 value below the lower threshold. Sets the number of stallGuard2 readings above the 0…3 upper threshold necessary for each current decrement of the motor current. Sets the lower motor current limit for coolStep operation by scaling the IRUN current setting. Lower ramp generator velocity threshold. Below this velocity coolStep becomes disabled. Adapt to the lower limit of the velocity range where stallGuard2 gives a stable result. 0 1 1… 2^23 Hint: May be adapted to disable coolStep during acceleration and deceleration phase by setting identical to VMAX. Upper ramp generator velocity threshold value. 1… Above this velocity coolStep becomes disabled. 2^23 Adapt to the velocity range where stallGuard2 gives a stable result. Description Range This status value provides the actual motor 0…31 current scale as controlled by coolStep. The value goes up to the IRUN value and down to the portion of IRUN as specified by SEIMIN. www.trinamic.com Comment step width is 1, 2, 4, 8 number of stallGuard2 measurements per decrement: 32, 8, 2, 1 0: 1/2 of IRUN 1: 1/4 of IRUN Also controls additional functions like switching to fullstepping. Comment 1/32, 2/32, … 32/32 TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 49 11.3 Tuning coolStep Before tuning coolStep, first tune the stallGuard2 threshold level SGT, which affects the range of the load measurement value SG. coolStep uses SG to operate the motor near the optimum load angle of +90°. The current increment speed is specified in SEUP, and the current decrement speed is specified in SEDN. They can be tuned separately because they are triggered by different events that may need different responses. The encodings for these parameters allow the coil currents to be increased much more quickly than decreased, because crossing the lower threshold is a more serious event that may require a faster response. If the response is too slow, the motor may stall. In contrast, a slow response to crossing the upper threshold does not risk anything more serious than missing an opportunity to save power. coolStep operates between limits controlled by the current scale parameter IRUN and the seimin bit. 11.3.1 Response Time For fast response to increasing motor load, use a high current increment step SEUP. If the motor load changes slowly, a lower current increment step can be used to avoid motor oscillations. If the filter controlled by sfilt is enabled, the measurement rate and regulation speed are cut by a factor of four. Hint: The most common and most beneficial use is to adapt coolStep for operation at the typical system target operation velocity and to set the velocity thresholds according. As acceleration and decelerations normally shall be quick, they will require the full motor current, while they have only a small contribution to overall power consumption due to their short duration. 11.3.2 Low Velocity and Standby Operation Because coolStep is not able to measure the motor load in standstill and at very low RPM, a lower velocity threshold is provided in the ramp generator. It should be set to an application specific default value. Below this threshold the normal current setting via IRUN respectively IHOLD is valid. An upper threshold is provided by the VHIGH setting. Both thresholds can be set as a result of the stallGuard2 tuning process. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 50 12 Sine-Wave Look-up Table Each of the TMC5031 drivers provides a programmable look-up table for storing the microstep current wave. As a default, the tables are pre-programmed with a sine wave, which is a good starting point for most stepper motors. Reprogramming the table to a motor specific wave allows drastically improved microstepping especially with low-cost motors. 12.1 User Benefits Microstepping Motor Torque – – – extremely improved with low cost motors runs smooth and quiet reduced mechanical resonances yields improved torque 12.2 Microstep Table In order to minimize required memory and the amount of data to be programmed, only a quarter of the wave becomes stored. The internal microstep table maps the microstep wave from 0° to 90°. It becomes symmetrically extended to 360°. When reading out the table the 10-bit microstep counter MSCNT addresses the fully extended wave table. The table is stored in an incremental fashion, using each one bit per entry. Therefore only 256 bits (ofs00 to ofs255) are required to store the quarter wave. These bits are mapped to eight 32 bit registers. Each ofs bit controls the addition of an inclination Wx or Wx+1 when advancing one step in the table. When Wx is 0, a 1 bit in the table at the actual microstep position means “add one” when advancing to the next microstep. As the wave can have a higher inclination than 1, the base inclinations Wx can be programmed to -1, 0, 1, or 2 using up to four flexible programmable segments within the quarter wave. This way even a negative inclination can be realized. The four inclination segments are controlled by the position registers X1 to X3. Inclination segment 0 goes from microstep position 0 to X1-1 and its base inclination is controlled by W0, segment 1 goes from X1 to X2-1 with its base inclination controlled by W1, etc. When modifying the wave, care must be taken to ensure a smooth and symmetrical zero transition when the quarter wave becomes expanded to a full wave. The maximum resulting swing of the wave should be adjusted to a range of -248 to 248, in order to give the best possible resolution while leaving headroom for the hysteresis based chopper to add an offset. W3: -1/+0 W2: +0/+1 W1: +1/+2 W0: +2/+3 y 256 248 START_SIN90_120 0 X1 X2 X3 LUT stores entries 0 to 255 255 256 START_SIN -248 Figure 12.1 LUT programming example www.trinamic.com 512 768 0 MSCNT TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 51 When the microstep sequencer advances within the table, it calculates the actual current values for the motor coils with each microstep and stores them to the registers CUR_A and CUR_B. However the incremental coding requires an absolute initialization, especially when the microstep table becomes modified. Therefore CUR_A and CUR_B become initialized whenever MSCNT passes zero. Two registers control the starting values of the tables: - As the starting value at zero is not necessarily 0 (it might be 1 or 2), it can be programmed into the starting point register START_SIN. - In the same way, the start of the second wave for the second motor coil needs to be stored in START_SIN90_120. This register stores the resulting table entry for a phase shift of 90° for 2-phase stepper motors. Hints: Refer chapter 5.3 for the register set and for the default table function stored in the drivers. The default table is a good base for realizing an own table. The TMC5031-EVAL will come with a calculation tool for own waves. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 52 13 Clock Oscillator and Clock Input The clock is the timing reference for all functions: the chopper, the velocity, the acceleration control, etc. Many parameters are scaled with the clock frequency, thus a precise reference allows a more deterministic result. The on-chip clock oscillator provides timing in case no external clock is easily available. USING THE INTERNAL CLOCK Directly tie the CLK input to GND near to the TMC5031 if the internal clock oscillator is to be used. The internal clock can be calibrated by driving the ramp generator at a certain velocity setting. Reading out position values via the interface and comparing the resulting velocity to the remote masters’ clock gives a time reference. This allows scaling acceleration and velocity settings as a result. The temperature dependency and ageing of the internal clock is comparatively low. In case well defined velocity settings and precise motor chopper operation are desired, it is supposed to work with an external clock source. USING AN EXTERNAL CLOCK When an external clock is available, a frequency of 12 MHz to 16 MHz is recommended for optimum performance. The duty cycle of the clock signal is uncritical, as long as minimum high or low input time for the pin is satisfied (refer to electrical characteristics). Up to 18 MHz can be used, when the clock duty cycle is 50%. Make sure, that the clock source supplies clean CMOS output logic levels and steep slopes when using a high clock frequency. The external clock input is enabled with the first positive polarity seen on the CLK input. Attention: Switching off the external clock frequency prevents the driver from operating normally. Therefore be careful to switch off the motor drivers before switching off the clock (e.g. using the enable input), because otherwise the chopper would stop and the motor current level could rise uncontrolled. The short to GND detection stays active even without clock, if enabled. 13.1 Considerations on the Frequency A higher frequency allows faster step rates, faster SPI operation and higher chopper frequencies. On the other hand, it may cause more electromagnetic emission of the system and causes more power dissipation in the TMC5031 digital core and voltage regulator. Generally a frequency of 12 MHz to 16 MHz should be sufficient for most applications. For reduced requirements concerning the motor dynamics, a clock frequency of down to 8 MHz can be considered. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 53 14 Absolute Maximum Ratings The maximum ratings may not be exceeded under any circumstances. Operating the circuit at or near more than one maximum rating at a time for extended periods shall be avoided by application design. Parameter Supply voltage I/O supply voltage digital VCC supply voltage (if not supplied by internal regulator) Logic input voltage Maximum current to / from digital pins and analog low voltage I/Os 5V regulator output current (internal plus external load) 5V regulator continuous power dissipation (VVM-5V) * I5VOUT Power bridge repetitive output current (TJ ≤ 105°C) Power bridge repetitive output current (TJ ≤ 125°C) Power bridge repetitive output current (TJ = 150°C) Junction temperature Storage temperature ESD-Protection for interface pins (Human body model, HBM) ESD-Protection for handling (Human body model, HBM) Symbol VVS VVIO VVCC Min -0.5 -0.5 -0.5 Max 18 5.5 5.5 Unit V V V VI IIO -0.5 VVIO+0.5 +/-10 V mA 50 1 2.0 1.5 0.8 150 150 4 (tbd.) mA W A A A °C °C kV 1 (tbd.) kV Max 125 16 5.4 5.25 5.25 Unit °C V V V V 1.1 1.5 A A I5VOUT P5VOUT IOx IOx IOx TJ TSTG VESDAP -50 -55 VESD 15 Electrical Characteristics 15.1 Operational Range Parameter Junction temperature Supply voltage (using internal +5V regulator) Supply voltage (internal +5V regulator bridged: VVCC=VVSA) I/O supply voltage VCC voltage when using optional external source (supplies digital logic and charge pump) Peak output current per motor coil output (sine wave peak) Peak output current per motor coil output (sine wave peak) Limit TJ ≤ 105°C, e.g. with 50% duty cycle at 3s on / 3s off. www.trinamic.com Symbol TJ VVS VVS VVIO VVCC IOx IOx Min -40 5.5 4.7 3.00 4.75 TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 54 15.2 DC Characteristics and Timing Characteristics DC characteristics contain the spread of values guaranteed within the specified supply voltage range unless otherwise specified. Typical values represent the average value of all parts measured at +25°C. Temperature variation also causes stray to some values. A device with typical values will not leave Min/Max range within the full temperature range. Power supply current DC-Characteristics VVS = 16.0V Parameter Supply current, driver disabled Supply current, operating Symbol IVS IVS Static supply current Supply current, driver disabled, dependency on CLK frequency Internal current consumption from 5V supply on VCC pin IO supply current IVS0 IVS Motor driver section DC- and Timing-Characteristics VVS = 16.0V Parameter RDSON lowside MOSFET Symbol RONL RDSON highside MOSFET RONH slope, MOSFET turning on tSLPON slope, MOSFET turning off tSLPOFF Current sourcing, driver off IOIDLE Charge pump DC-Characteristics Parameter Charge pump output voltage Symbol VVCP-VVS Charge pump voltage threshold for undervoltage detection Charge pump frequency VVCP-VVS Linear regulator DC-Characteristics Parameter Output voltage IVCC IVIO Conditions fCLK=16MHz fCLK=16MHz, 40kHz chopper fCLK=0Hz fCLK variable, additional to IVS0 fCLK=16MHz, 40kHz chopper no load on outputs, inputs at VIO or GND Conditions measure at 100mA, 25°C, static state measure at 100mA, 25°C, static state measured at 700mA load current measured at 700mA load current OXX pulled to GND Conditions operating, typical fchop<40kHz using internal 5V regulator voltage Min V5VOUT Max 40 7 1.6 30 Min Unit mA mA mA mA/MHz 40 10 mA µA Typ 0.4 Max 0.5 Unit Ω 0.5 0.6 Ω 120 250 ns 220 450 ns 120 180 250 µA Min 4.0 Typ V5VOUT 0.4 3.6 Max V5VOUT 3.3 fCP Symbol Typ 30 33 Unit V 3.8 V 1/16 fCLKOSC Conditions Min Typ Max Unit I5VOUT = 0mA 4.75 5.0 5.25 V TJ = 25°C Output resistance R5VOUT Static load 3 Deviation of output voltage over the full temperature range V5VOUT(DEV) I5VOUT = 30mA 30 www.trinamic.com TJ = full range 100 mV TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 55 Clock oscillator and input Timing-Characteristics Parameter Clock oscillator frequency Clock oscillator frequency Clock oscillator frequency External clock frequency (operating) External clock high / low level time Symbol fCLKOSC fCLKOSC fCLKOSC fCLK Conditions tJ=-50°C tJ=50°C tJ=150°C tCLK CLK driven to 0.1 VVIO / 0.9 VVIO Detector levels DC-Characteristics Parameter VVS undervoltage threshold for RESET V5VOUT undervoltage threshold for RESET Short to GND detector threshold (VVSP - VOx) Short to GND detector delay (high side switch on to short detected) Overtemperature prewarning Overtemperature shutdown Symbol VUV Conditions VVS rising VUV V5VOUT rising Sense resistor voltage levels DC-Characteristics Parameter Sense input peak threshold voltage (low sensitivity) Symbol VSRTL sense input peak threshold voltage (high sensitivity) VSRTH VOS2G Min 8.8 9.4 9.6 8 Parameter Min 3.8 Unit MHz MHz MHz MHz ns Typ 4.2 Max 4.6 3.5 Unit V V 1.5 2.2 3 V tS2G High side output clamped to VSP-3V 0.8 1.3 2 µs tOTPW tOT Temperature rising Temperature rising 100 135 120 150 140 170 °C °C Min Typ 325 Max Unit mV Conditions vsense=0 csactual=31 sin_x=248 Hyst.=0; IBRxy=0 vsense=1 csactual=31 sin_x=248 Hyst.=0; IBRxy=0 180 mV 20 mΩ DC-Characteristics Symbol Input voltage low level Input voltage high level Input Schmitt trigger hysteresis VINLO VINHI VINHYST Output voltage low level Output voltage high level Input leakage current VOUTLO VOUTHI IILEAK www.trinamic.com Max 17.9 18.8 18.9 18 25 Internal resistance from pin BRxy RBRxy to internal sense comparator (additional to sense resistor) Digital logic levels Typ 12.4 13.2 13.4 12-16 Conditions Min Typ -0.3 0.7 VVIO Max 0.3 VVIO VVIO+0.3 V V V 0.2 V V µA 0.12 VVIO IOUTLO = 2mA IOUTHI = -2mA VVIO-0.2 -10 Unit 10 TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 56 15.3 Thermal Characteristics The following table shall give an idea on the thermal resistance of the QFN-48 package. The thermal resistance for a four layer board will provide a good idea on a typical application. The single layer board example is kind of a worst case condition, as the typical application will require a 4 layer board. Actual thermal characteristics will depend on the PCB layout, PCB type and PCB size. A thermal resistance of 23°C/W for a typical board means, that the package is capable of continuously dissipating 4W at an ambient temperature of 25°C with the die temperature staying below 125°C. Parameter Symbol Conditions Typ Unit Thermal resistance junction to ambient on a single layer board RTJA Single signal layer board (1s) as defined in JEDEC EIA JESD51-3 (FR4, 76.2mm x 114.3mm, d=1.6mm) 80 K/W Thermal resistance junction to ambient on a multilayer board RTMJA Dual signal and two internal power plane board (2s2p) as defined in JEDEC EIA JESD51-5 and JESD51-7 (FR4, 76.2mm x 114.3mm, d=1.6mm) 23 K/W Thermal resistance junction to ambient on a multilayer board with air flow RTMJA1 Identical to RTMJA, but with air flow 1m/s 20 K/W Thermal resistance junction to board RTJB PCB temperature measured within 1mm distance to the package 10 K/W Thermal resistance junction to case RTJC Junction temperature to heat slug of package 3 K/W The thermal resistance in an actual layout can be tested by checking for the heat up caused by the standby power consumption of the chip. When no motor is attached, all power seen on the power supply is dissipated within the chip. Note: A spread-sheet for calculating TMC5031 power dissipation is available on www.trinamic.com. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 57 16 Layout Considerations 16.1 Exposed Die Pad The TMC5031 uses its die attach pad to dissipate heat from the drivers and the linear regulator to the board. For best electrical and thermal performance, use a reasonable amount of solid, thermally conducting vias between the die attach pad and the ground plane. The printed circuit board should have a solid ground plane spreading heat into the board and providing for a stable GND reference. 16.2 Wiring GND All signals of the TMC5031 are referenced to their respective GND. Directly connect all GND pins under the TMC5031 to a common ground area (GND, GNDP, GNDA and die attach pad). The GND plane right below the die attach pad should be treated as a virtual star point. For practical reasons, this has to be the PCB GND layer, not the PCB top layer. Attention! Especially, the sense resistors are susceptible to GND differences and GND ripple voltage, as the microstep current steps make up for voltages down to 0.5 mV. No current other than the sense resistor current should flow on their connections to GND and to the TMC5031. Optimally place them close to the TMC5031, with one or more vias to the GND plane for each sense resistor. The two sense resistors for one coil should not share a common ground connection trace or vias, as also PCB traces have a certain resistance. 16.3 Supply Filtering The 5VOUT output voltage ceramic filtering capacitor (4.7 µF recommended) should be placed as close as possible to the 5VOUT pin, with its GND return going directly to the GNDA pin. Use as short and as thick connections as possible. For best microstepping performance and lowest chopper noise an additional filtering capacitor can be used for the VCC pin to GND, to avoid charge pump and digital part ripple influencing motor current regulation. Therefore place a ceramic filtering capacitor (470nF recommended) as close as possible (1-2mm distance) to the VCC pin with GND return going to the ground plane. VCC can be coupled to 5VOUT using a 2.2 Ω or 3.3 Ω resistor in order to supply the digital logic from 5VOUT while keeping ripple away from this pin. A 100 nF filtering capacitor should be placed as close as possible to the VSA pin to ground plane. The motor supply pins VS should be decoupled with an electrolytic capacitor (47 μF or larger is recommended) and a ceramic capacitor, placed close to the device. Take into account that the switching motor coil outputs have a high dV/dt. Thus capacitive stray into high resistive signals can occur, if the motor traces are near other traces over longer distances. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 58 16.4 Layout Example 1- Top Layer (assembly side) 2- Inner Layer (GND) 3- Inner Layer (supply VS) 4- Bottom Layer Components Figure 16.1 Layout example www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 59 17 Package Mechanical Data 17.1 Dimensional Drawings Attention: Drawings not to scale. Figure 17.1 Dimensional drawings Parameter total thickness stand off mold thickness lead frame thickness lead width body size X body size Y lead pitch exposed die pad size X exposed die pad size Y lead length package edge tolerance mold flatness coplanarity lead offset exposed pad offset Ref A A1 A2 A3 b D E e J K L aaa bbb ccc ddd eee Min 0.80 0.00 0.2 5.2 5.2 0.35 Nom 0.85 0.035 0.65 0.203 0.25 7.0 7.0 0.5 5.3 5.3 0.4 Max 0.90 0.05 0.67 0.3 5.4 5.4 0.45 0.1 0.1 0.08 0.1 0.1 17.2 Package Codes Type TMC5031 www.trinamic.com Package QFN48 (RoHS) Temperature range -40°C ... +125°C Code & marking TMC5031-ES TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 60 18 Getting Started Please refer to the TMC5031-EVAL evaluation board to allow a quick start with the device, and in order to allow interactive tuning of the device setup in your application. It will guide you through the process of correctly setting up all registers. The following example gives a minimum set of accesses allowing moving a motor. 18.1 Initialization Examples Initialization SPI datagram example sequence to enable and initialize driver 1 for operation: SPI SPI SPI SPI SPI SPI send: send: send: send: send: send: 0x8000000008; 0xEC00010445; 0xB000011F05; 0xA600001388; 0xA700004E20; 0xA000000001; // // // // // // GCONF=8: Enable PP and INT outputs CHOPCONF: TOFF=5, HSTRT=4, HEND=8, TBL=2, CHM=0 (spreadCycle) IHOLD_IRUN: IHOLD=5, IRUN=31 (max. current), IHOLDDELAY=1 AMAX=5000 VMAX=20000 RAMPMODE=1 (positive velocity) // Now motor 1 should start rotating SPI send: 0x2100000000; // Query X Actual – The next read access delivers X Actual SPI read; // Read X Actual The configuration parameters should be tuned to the motor and application for optimum performance. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 61 19 Disclaimer TRINAMIC Motion Control GmbH & Co. KG does not authorize or warrant any of its products for use in life support systems, without the specific written consent of TRINAMIC Motion Control GmbH & Co. KG. Life support systems are equipment intended to support or sustain life, and whose failure to perform, when properly used in accordance with instructions provided, can be reasonably expected to result in personal injury or death. Information given in this data sheet is believed to be accurate and reliable. However no responsibility is assumed for the consequences of its use nor for any infringement of patents or other rights of third parties which may result from its use. Specifications are subject to change without notice. All trademarks used are property of their respective owners. 20 ESD Sensitive Device The TMC5031 is an ESD sensitive CMOS device sensitive to electrostatic discharge. Take special care to use adequate grounding of personnel and machines in manual handling. After soldering the devices to the board, ESD requirements are more relaxed. Failure to do so can result in defect or decreased reliability. www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 62 21 Table of Figures Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure 1.1 Basic application and block diagram .......................................................................................................... 4 1.2 Energy efficiency with coolStep (example) ............................................................................................... 6 2.1 TMC5031 pin assignments. ............................................................................................................................. 7 3.1 Standard application circuit ......................................................................................................................... 10 3.2 External supply of VCC_IO ............................................................................................................................ 11 3.3 5V only operation ........................................................................................................................................... 12 3.4 Using an external 5V supply to reduce linear regulator power dissipation ................................. 13 3.5 Adding an RC-Filter on VCC for reduced ripple ..................................................................................... 13 4.1 SPI timing ......................................................................................................................................................... 16 7.1 Chopper phases .............................................................................................................................................. 32 7.2 spreadCycle chopper scheme showing coil current during a chopper cycle ............................... 35 7.3 Classic const. off time chopper with offset showing coil current................................................... 36 7.4 Zero crossing with classic chopper and correction using sine wave offset................................. 36 9.1 Ramp generator velocity trace showing consequent move in negative direction ..................... 41 9.2 Illustration of optimized motor torque usage with TMC5031 ramp generator ........................... 41 9.3 Ramp generator velocity dependent motor control ............................................................................ 42 9.4 Using reference switches (example) ......................................................................................................... 43 10.1 Function principle of stallGuard2 ............................................................................................................ 44 10.2 Example: Optimum SGT setting and stallGuard2 reading with an example motor ................. 45 11.1 coolStep adapts motor current to the load ......................................................................................... 48 12.1 LUT programming example ....................................................................................................................... 50 16.1 Layout example ............................................................................................................................................. 58 17.1 Dimensional drawings ................................................................................................................................ 59 www.trinamic.com TMC5031 DATASHEET (Rev. 1.07 / 2013-APR-30) 63 22 Revision History Version Date Author Description BD – Bernhard Dwersteg SD – Sonja Dwersteg 1.04 2012_NOV-18 BD / SD 1.05 1.06 2013_FEB-22 2013-MAR-25 JP SD 1.07 2013-APR-30 SD First version of product TMC5031 datasheet based on TMC562 prototype datasheet V1.04 Product Image changed - Chapter 15.3 (thermal characteristics) added. - Chapter 10.1 (tuning the stallGuard2 threshold) updated. - CSACTUAL in DRV_STATUS corrected (chapter 5.3.4). - Interrupt output remark in RAMP_STAT for status_latch_l and status_latch_r removed. Description event_stop_l and event_stop_r updated (chapter 6.2.2.2) - Description of the reference switch actions improved. - SW_MODE register updated. - Order codes updated. - Consecutive numbering of the document corrected. New description of VCC_IO requirements. Table 22.1 Documentation revisions 23 References [AN001] Trinamic Application Note 001 - Parameterization of spreadCycle™, www.trinamic.com [AN002] Trinamic Application Note 002 - Parameterization of stallGuard2™ & coolStep™, www.trinamic.com www.trinamic.com