AMIS-30521 Micro-stepping Motor Driver Data Sheet 1.0 Introduction The AMIS-30521 is a micro-stepping stepper motor driver for bipolar stepper motors. The chip is connected through I/O pins and an SPI interface with an external microcontroller. The AMIS-30521 contains a current-translation table and takes the next micro-step depending on the clock signal on the “NXT” input pin and the status of the “DIR” (=direction) register or input pin. The chip provides a so-called “speed and load angle” output. This allows the creation of stall detection algorithms and control loops based on load-angle to adjust torque and speed. It is using a proprietary PWM algorithm for reliable current control. The AMIS-30521 is implemented in I2T100 technology, enabling both high-voltage analog circuitry and digital functionality on the same chip. The chip is fully compatible with the automotive voltage requirements. The AMIS-30521 is ideally suited for general-purpose stepper motor applications in the automotive, industrial, medical, and marine environment. 2.0 Key Features • • • • • • • • • • • • • Dual H-Bridge for 2-phase stepper motors Programmable peak-current up to 1.6A using a 5-bit current DAC On-chip current translator SPI interface Speed and load angle output Seven step modes from full-step up to 32 micro-steps Fully integrated current-sense PWM current control with automatic selection of fast and slow decay Low EMC PWM with selectable voltage slopes Active fly-back diodes Full output protection and diagnosis Thermal warning and shutdown Compatible with 5V and 3.3V microcontrollers 3.0 Ordering information Table 1: Ordering Information Part No. AMIS-30521 ANA Package Peak Current Temp. Range NQFP-32 (7 x 7mm) 1600mA -40°C…..125°C AMI Semiconductor – June 2007, M-20683-001 www.amis.com 1 Ordering Code Tubes 0C521-001-XTD Ordering Code Tapes 0C521-001-XTP AMIS-30521 Micro-stepping Motor Driver Data Sheet 4.0 Block Diagram VDD CLK Timebase CPN CPP VCP Chargepump POR CS DI OTP SPI DO NXT Logic & Registers DIR VBB Load Angle SLA Temp. Sense EMC T R A N S L A T O R MOTXP P W M I-sense EMC MOTYP P W M MOTYN I-sense CLR Bandgap ERR AMIS-30521 GND PC20070322.1 Figure 1: Block Diagram AMIS-30521 5.0 Pin Description Table 2: Pin List and Description Name Pin DO 31 VDD 32 GND 1 DI 2 CLK 3 NXT 4 DIR 5 ERRB 6 SLA 7 CPN 9 CPP 10 VCP 11 CLR 12 CSB 13 VBB 14 MOTYP 15, 16 GND 17, 18 MOTYN 19, 20 MOTXN 21, 22 GND 23, 24 MOTXP 25, 26 VBB 27 / 8, 28, 30 TST0 29 Description SPI data output Logic Supply Input (needs external decoupling capacitor) Ground, heat sink SPI data in SPI clock input Next micro-step input Direction input Error Output Speed Load Angle Output Negative connection of charge pump capacitor Positive connection of charge pump capacitor Charge-pump filter-capacitor “Clear” = Chip Reset input SPI chip select input High Voltage Supply Input Negative end of phase Y coil output Ground, heat sink Positive end of phase Y coil output Positive end of phase X coil output Ground, heat sink Negative end of phase X coil output High Voltage Supply Input No Function (to be left open in normal operation) Test pin (to be tied to ground in normal operation) input AMI Semiconductor – June 2007, M-20683-001 www.amis.com 2 MOTXN AMIS-30521 Micro-stepping Motor Driver 28 MOTXP 29 MOTXP 30 VBB DO 31 TSTO VDD GND 32 27 26 25 GND 1 24 DI CLK NXT 2 23 3 22 DIR 5 20 MOTYN ERR 6 19 SLA 7 18 8 17 MOTYN GND GND 4 21 AMIS-30521 13 14 15 GND MOTXN MOTXN 16 MOTYP CS 12 MOTYP VBB CPP CPN 11 VCP 10 CLR 9 Data Sheet PC20070309.2 Figure 2: Pin Out AMIS-30521 5.1 Package Thermal Characteristics The NQFP is designed to provide superior thermal performance, and using an exposed die pad on the bottom surface of the package partly contributes to this. In order to take full advantage of this thermal performance, the PCB must have features to conduct heat away from the package. A thermal grounded pad with thermal vias can achieve this. With a layout as shown in Figure 3: PCB Ground Plane Layout Condition, the thermal resistance junction – to – ambient can be brought down to a level of 30°C/W. NQFP-32 PC20041128.2 Figure 3: PCB Ground Plane Layout Condition AMI Semiconductor – June 2007, M-20683-001 www.amis.com 3 AMIS-30521 Micro-stepping Motor Driver Data Sheet 6.0 Electrical Specification 6.1 Absolute Maximum Ratings Stresses above those listed in table below may cause immediate and permanent device failure. It is not implied that more that one of these conditions can be applied simultaneously. Table 3: Absolute Maximum Ratings Symbol Parameter (1) VBB Analog DC supply voltage VDD Logic supply voltage Tstrg Storage temperature Tamb Ambient temperature under bias (2) VESD Electrostatic discharges on component level Notes: (1) (2) Min. -0.3 -0.3 -55 -50 -2 Max. +40 +7.0 +160 +150 +2 Units V V °C °C kV For limited time <0.5s. Human body model (100pF via 1.5 kΩ, according to JEDEC EIA-JESD22-A114-B). 6.2 Recommend Operation Conditions Operating ranges define the limits for functional operation and parametric characteristics of the device. Note that the functionality of the chip outside these operating ranges is not guaranteed. Operating outside the recommended operating ranges for extended periods of time may affect device reliability. Table 4: Operating Ranges Symbol Parameter VBB Analog DC supply VDD Logic supply voltage (1) Iddd Dynamic current Ta Ambient temperature VBAT≤+18 Ta Ambient temperature VBAT≤+29 Tj Junction temperature Notes: (1) Min. +6 4.75 -40 -40 Dynamic current is with oscillator running, all analogue cells active. All outputs unloaded, no floating inputs. AMI Semiconductor – June 2007, M-20683-001 www.amis.com 4 Max. +30 5.25 18 +125 +85 +160 Unites V V mA °C °C °C AMIS-30521 Micro-stepping Motor Driver Data Sheet 6.3 DC Parameters The DC parameters are given for VBB and temperature in their operating ranges unless otherwise specified. Convention: currents flowing in the circuit are defined as positive. Table 5: DC Parameters Symbol Pin(s) Parameter Supply Inputs VBB Nominal operating supply range VBB Ibat Total current consumption Vdd VDD Logic supply voltage Power-on-Reset (POR) VDDH Internal POR comparator threshold VDD VDDL Internal POR comparator threshold Motordriver Max current through motor coil in IMDmax,Peak normal operation Max RMS current through coil in normal IMDmax,RMS operation IMDabs Absolute error on coil current IMDrel Error on current ratio Icoilx / Icoily On-resistance high-side driver, RHS MOTXP CUR[4:0] = 0...31 MOTXN On-resistance low-side driver, RLS3 MOTYP CUR[4:0] = 23...31 MOTYN On-resistance low-side driver, RLS2 CUR[4:0] = 16...22 On-resistance low-side driver, RLS1 CUR[4:0] = 9...15 On-resistance low-side driver, RLS0 CUR[4:0] = 0...8 IMpd Pull-down current Logic Inputs (3) Ileak DI, CLK Input leakage NXT, DIR Logic low threshold VinL CLR, CSB Logic high threshold VinH CLR Rpd Internal pull-down resistor TST0 Thermal Warning and Shutdown Ttw Thermal warning (1) (2) Ttsd Thermal shutdown Charge Pump Vcp VCP Cbuffer Cpump Output voltage Remark/Test Conditions Typ. Max. Unit 4.75 5 30 8 5.25 V mA V 4.0 4.25 3.68 4.4 V V 6 Unloaded outputs VDD rising VDD falling 1600 mA 800 -10 -7 Vbb = 12V, Tj = 27 °C Vbb = 12V, Tj = 160 °C Vbb = 12V, Tj = 27 °C Vbb = 12V, Tj = 160 °C Vbb = 12V, Tj = 27 °C Vbb = 12V, Tj = 160 °C Vbb = 12V, Tj = 27 °C Vbb = 12V, Tj = 160 °C Vbb = 12V, Tj = 27 °C Vbb = 12V, Tj = 160 °C HiZ mode 0.45 0.94 0.45 0.94 0.90 1.9 1.8 3.8 3.6 7.5 0.5 Tj = 160 °C mA 10 7 0.56 1.25 0.56 1.25 1.2 2.5 2.3 5.0 4.5 10 % % Ω Ω Ω Ω Ω Ω Ω Ω Ω Ω mA 1 1.5 µA V V 300 kΩ 152 °C °C 3.5 120 138 6V< VBB < 15V 15V < VBB < 30V External buffer capacitor CPP CPN External pump capacitor Notes: (1) No more than 100 cumulated hours in life time above Ttw. (2) Thermal shutdown and low temperature warning are derived from thermal warning. (3) Not valid for pins with internal pull-down resistor. AMI Semiconductor – June 2007, M-20683-001 www.amis.com Min. 5 VBB+12.5 180 180 145 Ttw + 20 2 * VBB – 2.5 VBB+14 220 220 VBB+15.5 470 470 V V nF nF AMIS-30521 Micro-stepping Motor Driver Data Sheet 6.4 AC Parameters The AC parameters are given for VBB and temperature in their operating ranges. Table 6: AC Parameters Symbol Pin(s) Parameter Internal Oscillator fosc Frequency of internal oscillator Motordriver PWM frequency fPWM Double PWM frequency MOTxx fj PWM Jitter frequency fd PWM Jitter depth Remark/Test Conditions Frequency depends only on internal oscillator Tbrise MOTxx turn-on voltage slope, 10% to 90% Tbfall MOTxx turn-off voltage slope, 90% to 10% Digital Outputs DO ERRB Charge Pump fCP CPN CPP TCPU MOTxx CLR Function TCLR CLR TH2L Min. Typ. Max. Unit 3.6 4 4.4 MHz 20.8 41.6 22.8 45.6 tbd tbd 150 100 50 25 150 100 50 25 24.8 49.6 kHz kHz Hz % fPWM V/µs V/µs V/µs V/µs V/µs V/µs V/µs V/µs 50 ns EMC[1:0] = 00 EMC[1:0] = 01 EMC[1:0] = 10 EMC[1:0] = 11 EMC[1:0] = 00 EMC[1:0] = 01 EMC[1:0] = 10 EMC[1:0] = 11 Capacitive load 400pF and pullup resistor of 1.5 kΩ Output fall-time from VinH to VinL Charge pump frequency Start-up time of charge pump 250 kHz Spec external components Hard reset duration time 20 90 µs Max. Unit µs ns ns ns ns µs ns ns 6.5 SPI Timing Table 7: SPI Timing Parameters Symbol Parameter tCLK SPI clock period tCLK_HIGH SPI clock high time tCLK_LOW SPI clock low time tSET_DI DI set up time, valid data before rising edge of CLK tHOLD_DI DI hold time, hold data after rising edge of CLK tCSB_HIGH CSB high time tSET_CSB CSB set up time, CSB low before rising edge of CLK tSET_CLK CLK set up time, CLK low before rising edge of CSB Min. 1 100 100 50 50 2.5 100 100 0,2 VCC CS 0,2 VCC tSET_CSB tCLK tSET_CLK 0,8 VCC CLK 0,2 VCC 0,2 VCC tCLK_HI tSET_DI DI tCLK_LO tHOLD_DI 0,8 VCC VALID PC20070608.1 Figure 4: SPI Timing AMI Semiconductor – June 2007, M-20683-001 www.amis.com 6 Typ. AMIS-30521 Micro-stepping Motor Driver Data Sheet 7.0 Typical Application Schematic 100 nF VDD C4 100 nF C2 D1 100 nF C6 C5 100 nF VDD VBAT C1 C3 VBB VBB 100 µF 220 nF VCP CPN DIR 220 nF NXT CPP DO MOTXP DI µC C7 CLK AMIS-30521 MOTXN CS MOTYP CLR ERR M MOTYN SLA C8 R1 GND PC20070604.11 Figure 5: Typical Application Schematic AMIS-30521 Table 8: External Components List and Description Component Function (1) C1 VBB buffer capacitor C2, C3 VBB decoupling block capacitor C4 VDD buffer capacitor C5 VDD buffer capacitor C6 Charge pump buffer capacitor C7 Charge pump pumping capacitor C8 Low pass filter SLA R1 Low pass filter SLA D1 Optional reverse protection diode Typ. Value 100 100 220 100 220 220 1 5.6 e.g. 1N4003 Notes: (1) Low ESR < 1Ohm. AMI Semiconductor – June 2007, M-20683-001 www.amis.com 7 Tolerance -20 +80% -20 +80% +/- 20 % +/- 20% +/- 20% +/- 20% +/- 20% +/- 1% Unit µF nF nF nF nF nF nF kΩ AMIS-30521 Micro-stepping Motor Driver Data Sheet 8.0 Functional Description 8.1 H-Bridge Drivers A full H-bridge is integrated for each of the two stator windings. Each H-bridge consists of two low-side and two high-side N-type MOSFET switches. Writing logic ‘0’ in bit <MOTEN> disables all drivers (high-impedance). Writing logic ‘1’ in this bit enables both bridges and current can flow in the motor stator windings. In order to avoid large currents through the H-bridge switches, it is guaranteed that the top- and bottom-switches of the same halfbridge are never conductive simultaneously (interlock delay). A two-stage protection against shorts on motor lines is implemented. In a first stage, the current in the driver is limited. Secondly, when excessive voltage is sensed across the transistor, the transistor is switched-off. In order to reduce the radiated/conducted emission, voltage slope control is implemented in the output switches. The output slope is defined by the gate-drain capacitance of output transistor and the (limited) current that drives the gate. There are two trimming bits for slope control (Table 25: SPI Control Parameter Overview EMC[1:0]). The power transistors are equipped with so-called “active diodes”: when a current is forced trough the transistor switch in the reverse direction, i.e. from source to drain, then the transistor is switched on. This ensures that most of the current flows through the channel of the transistor instead of through the inherent parasitic drain-bulk diode of the transistor. Depending on the desired current range and the micro-step position at hand, the Rdson of the low-side transistors will be adapted such that excellent current-sense accuracy is maintained. The Rdson of the high-side transistors remain unchanged, see Table 5: DC Parameters for more details. 8.2 PWM Current Control A PWM comparator compares continuously the actual winding current with the requested current and feeds back the information to a digital regulation loop. This loop then generates a PWM signal, which turns on/off the H-bridge switches. The switching points of the PWM duty-cycle are synchronized to the on-chip PWM clock. The frequency of the PWM controller can be doubled and an artificial jitter can be added (Table 14: SPI Control Register 1). The PWM frequency will not vary with changes in the supply voltage. Also variations in motor-speed or load-conditions of the motor have no effect. There are no external components required to adjust the PWM frequency. 8.2.1. Automatic Forward and Slow-Fast Decay The PWM generation is in steady-state using a combination of forward and slow-decay. The absence of fast-decay in this mode, guarantees the lowest possible current-ripple “by design”. For transients to lower current levels, fast-decay is automatically activated to allow high-speed response. The selection of fast or slow decay is completely transparent for the user and no additional parameters are required for operation. Icoil Set value Actual value t 0 TPWM Forward & Slow Decay Forward & Slow Decay Fast Decay & Forward PC20070604.1 Figure 6: Forward and Slow/Fast Decay PWM AMI Semiconductor – June 2007, M-20683-001 www.amis.com 8 AMIS-30521 Micro-stepping Motor Driver Data Sheet 8.2.2. Automatic Duty Cycle Adaptation Incase the supply voltage is lower than 2*Bemf, then the duty cycle of the PWM is adapted automatically to >50% to maintain the requested average current in the coils. This process is completely automatic and requires no additional parameters for operation. The over-all current-ripple is divided by two if PWM frequency is doubled (Table 14: SPI Control Register 1). Icoil Duty Cycle < 50% Duty Cycle < 50% Duty Cycle >50% Actual value Set value t PC20070604.2 TPWM Figure 7: Automatic Duty Cycle Adaptation 8.3 Step Translator 8.3.1. Step Mode The step translator provides the control of the motor by means of SPI register Stepmode: SM[2:0], SPI register DIRCNTRL, and input pins DIR and NXT. It is translating consecutive steps in corresponding currents in both motor coils for a given step mode. One out of seven possible stepping modes can be selected through SPI-bits SM[2:0] (Table 26: SPI Control Parameter Overview SM[2:0]) After power-on or hard reset, the coil-current translator is set to the default 1/32 micro-stepping at position ‘0’. Upon changing the step mode, the translator jumps to position 0* of the corresponding stepping mode. When remaining in the same step mode, subsequent translator positions are all in the same column and increased or decreased with 1. Table 10: Circular Translator Table lists the output current versus the translator position. As shown in Figure 8 the output current-pairs can be projected approximately on a circle in the (Ix,Iy) plane. There is, however, one exception: uncompensated half step. In this step mode the currents are not regulated to a fraction of Imax but are in all intermediate steps regulated at 100 percent. In the (Ix,Iy) plane the current-pairs are projected on a square. Table 9: Square Translator Table for Umcompensated Half StepSM[2:0] = 101 lists the output current versus the translator position for this case. Table 9: Square Translator Table for Umcompensated Half StepSM[2:0] = 101 Stepmode ( SM[2:0] ) % of Imax 101 Coil x Coil y Uncompensated Half-Step 0* 0 100 1 100 100 2 100 0 3 100 -100 4 0 -100 5 -100 -100 6 -100 0 7 -100 100 AMI Semiconductor – June 2007, M-20683-001 www.amis.com 9 AMIS-30521 Micro-stepping Motor Driver Table 10: Circular Translator Table Stepmode ( SM[2:0] ) % of Imax 000 001 010 011 100 110 1/32 ‘0’ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 1/16 0* 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 - 1/8 0* 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 - 1/4 0* 1 2 3 4 5 6 7 - 1/2 0* 1 2 3 - FS 1 2 - Stepmode ( SM[2:0] ) Coil x Coil y 0 3.5 8.1 12.7 17.4 22.1 26.7 31.4 34.9 38.3 43 46.5 50 54.6 58.1 61.6 65.1 68.6 72.1 75.5 79 82.6 84.9 87.2 89.5 91.8 93 94.1 95.3 96.5 97.7 98.8 100 98.8 97.7 96.5 95.3 94.1 93 91.8 89.5 87.2 84.9 82.6 79 75.5 72.1 68.6 65.1 61.6 58.1 54.6 50 46.5 43 38.3 34.9 31.4 26.7 22.1 17.4 12.7 8.1 3.5 100 98.8 97.7 96.5 95.3 94.1 93 91.8 89.5 87.2 84.9 82.6 79 75.5 72.1 68.6 65.1 61.6 58.1 54.6 50 46.5 43 38.3 34.9 31.4 26.7 22.1 17.4 12.7 8.1 3.5 0 -3.5 -8.1 -12.7 -17.4 -22.1 -26.7 -31.4 -34.9 -38.3 -43 -46.5 -50 -54.6 -58.1 -61.6 -65.1 -68.6 -72.1 -75.5 -79 -82.6 -84.9 -87.2 -89.5 -91.8 -93 -94.1 -95.3 -96.5 -97.7 -98.8 AMI Semiconductor – June 2007, M-20683-001 www.amis.com Data Sheet 10 % of Imax 000 001 010 011 100 110 1/32 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 1/16 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 - 1/8 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 - 1/4 8 9 10 11 12 13 14 15 - 1/2 4 5 6 7 - FS 3 0* - Coil x Coil y 0 -3.5 -8.1 -12.7 -17.4 -22.1 -26.7 -31.4 -34.9 -38.3 -43 -46.5 -50 -54.6 -58.1 -61.6 -65.1 -68.6 -72.1 -75.5 -79 -82.6 -84.9 -87.2 -89.5 -91.8 -93 -94.1 -95.3 -96.5 -97.7 -98.8 -100 -98.8 -97.7 -96.5 -95.3 -94.1 -93 -91.8 -89.5 -87.2 -84.9 -82.6 -79 -75.5 -72.1 -68.6 -65.1 -61.6 -58.1 -54.6 -50 -46.5 -43 -38.3 -34.9 -31.4 -26.7 -22.1 -17.4 -12.7 -8.1 -3.5 -100 -98.8 -97.7 -96.5 -95.3 -94.1 -93 -91.8 -89.5 -87.2 -84.9 -82.6 -79 -75.5 -72.1 -68.6 -65.1 -61.6 -58.1 -54.6 -50 -46.5 -43 -38.3 -34.9 -31.4 -26.7 -22.1 -17.4 -12.7 -8.1 -3.5 0 3.5 8.1 12.7 17.4 22.1 26.7 31.4 34.9 38.3 43 46.5 50 54.6 58.1 61.6 65.1 68.6 72.1 75.5 79 82.6 84.9 87.2 89.5 91.8 93 94.1 95.3 96.5 97.7 98.8 AMIS-30521 Micro-stepping Motor Driver Data Sheet Iy Iy Start = 0 Start = 0 Step 1 Step 1 Step 2 Step 3 Step 2 Ix Ix Step 3 1/4th micro step SM[2:0] = 011 Uncompensated Half Step SM[2:0] = 101 PC20070604.5 Figure 8: Translator Table: Circular and Square 8.3.2. Direction The direction of rotation is selected by means of following combination of the DIR input pin and the SPI-controlled direction bit <DIRCTRL>. (Table 14: SPI Control Register 1) 8.3.3. NXT Input Changes on the NXT input will move the motor current one step up/down in the translator table. Depending on the NXT-polarity bit <NXTP> (Table 14: SPI Control Register 1), the next step is initiated either on the rising edge or the falling edge of the NXT input. tNXT_HI 0,5 VCC NXT tDIR_SET DIR tNXT_LO tDIR_HOLD VALID PC20070609.1 Figure 9: NXT-input Timing Diagram Table 11: Timing Table NXT Pin Symbol Parameter tNXT_HI NXT minimum, high pulse width tNXT_LO NXT minimum, low pulse width tDIR_SET NXT hold time, following change of DIR tDIR_HOLD NXT hold time, before change of DIR Min. 2 2 500 500 AMI Semiconductor – June 2007, M-20683-001 www.amis.com 11 Typ. Max. Unit µs µs µs µs AMIS-30521 Micro-stepping Motor Driver Data Sheet 8.3.4. Translator Position The translator position can be read in Table 30: SPI Status Register 3. This is a 7-bit number equivalent to the 1/32th micro-step from Table 10: Circular Translator Table. The translator position is updated immediately following a NXT trigger. NXT Update Translator Position Update Translator Position PC20070604.4 Figure 10: Translator Position Timing Diagram 8.3.5. Synchronization of Step Mode and NXT Input When step mode is re-programmed to another resolution (Table 13: SPI Control Register 0), then this is put in effect immediately upon the first arriving “NXT” input. If the micro-stepping resolution is increased (see Figure 11) then the coil currents will be regulated to the nearest micro-step, according to the fixed grid of the increased resolution. If however the micro-stepping resolution is decreased, then it is possible to introduce an offset (or phase shift) in the micro-step translator table. If the step resolution is decreased at a translator table position that is shared both by the old and new resolution setting, then the offset is zero and micro-stepping is proceeds according to the translator table. If the translator position is not shared both by the old and new resolution setting, then the micro-stepping proceeds with an offset relative to the translator table (See Figure 10 right hand side). Change from lower to higher resolution Iy Iy DIR NXT3 endpos NXT2 Iy DIR NXT1 NXT4 Iy DIR NXT1 endpos startpos Ix Halfstep Change from higher to lower resolution DIR startpos NXT2 Ix Ix 1/4th step 1/8th step Ix NXT3 Halfstep PC20070604.6 Figure 11: NXT-Step Mode Synchronization Left: Change from lower to higher resolution. The left-hand side depicts the ending half-step position during which a new step mode resolution was programmed. The right-hand side diagram shows the effect of subsequent NXT commands on the micro-step position. Right: Change from higher to lower resolution. The left-hand side depicts the ending micro-step position during which a new step mode resolution was programmed. The right-hand side diagram shows the effect of subsequent NXT commands on the half-step position. Note: It is advised to reduce the micro-stepping resolution only at micro-step positions that overlap with desired micro-step positions of the new resolution. AMI Semiconductor – June 2007, M-20683-001 www.amis.com 12 AMIS-30521 Micro-stepping Motor Driver Data Sheet 8.4 Programmable Peak-Current The amplitude of the current waveform in the motor coils (coil peak current = Imax) is adjusted by means of an SPI parameter "CUR[4:0]" (Table 13: SPI Control Register 0). Whenever this parameter is changed, the coil-currents will be updated immediately at the next PWM period. More information can be found in Table 24: SPI Control Parameter Overview CUR[4:0]. 8.5 Speed and Load Angle Output The SLA-pin provides an output voltage that indicates the level of the Back-e.m.f. voltage of the motor. This Back-e.m.f. voltage is sampled during every so-called "coil current zero crossings". Per coil, two zero-current positions exist per electrical period, yielding in total four zero-current observation points per electrical period. VBEMF ICOIL t ZOOM Previous Micro-step ICOIL Coil Current Zero Crossing Next Micro-step Current Decay Zero Current t VCOIL VBB Voltage Transient VBEMF t PC20070604.7 Figure 12: Principle of Bemf Measurement Because of the relatively high recirculation currents in the coil during current decay, the coil voltage VCOIL shows a transient behavior. As this transient is not always desired in application software, two operating modes can be selected by means of the bit <SLAT> (see "SLA-transparency" in Table 15: SPI Control Register 2). The SLA pin shows in "transparent mode" full visibility of the voltage transient behavior. This allows a sanity-check of the speed-setting versus motor operation and characteristics and supply voltage levels. If the bit “SLAT” is cleared, then only the voltage samples at the end of each coil current zero crossing are visible on the SLA-pin. Because the transient behavior of the coil voltage is not visible anymore, this mode generates smoother Back e.m.f. input for post-processing, e.g. by software. In order to bring the sampled Back e.m.f. to a descent output level (0 to 5V), the sampled coil voltage VCOIL is divided by 2 or by 4. This divider is set through an SPI bit <SLAG>. (Table 15: SPI Control Register 2) Table 12: Parameter Table SLA Pin Symbol Pin(s) Parameter Vout Output voltage range Voff Output offset the SLA pin Rout Output resistance SLA pin SLA Cload Load capacitance SLA pin Gsla Gain of SLA pin = VBEMF / VCOIL Remark/Test Conditions 0.2V < Vsla < Vdd - 0,2V SLAG=0 SLAG=1 AMI Semiconductor – June 2007, M-20683-001 www.amis.com 13 Min. 0.5 -20 Typ. 0,5 0,25 Max. 4.5 20 1 50 Unit V mV kΩ pF AMIS-30521 Micro-stepping Motor Driver Data Sheet The following drawing illustrates the operation of the SLA-pin and the transparency-bit. "PWMsh" and "Icoil=0" are internal signals that define together with SLAT the sampling and hold moments of the coil voltage. Ssh VCOIL Sh div2 div4 buf SLA-pin Ch Csh Icoil=0 PWMsh SLAT NOT(Icoil=0) PWMsh Icoil=0 SLAT VCOIL t SLA-pin last sample is retained VBEMF retain last sample previous output is kept at SLA pin t SLAT=1 => SLA-pin is "transparent" during VBEMF sampling @ Coil Current Zero Crossing. SLA-pin is updated "real-time". SLAT=0 => SLA-pin is not "transparent" during VBEMF sampling @ Coil Current Zero Crossing. SLA-pin is updated when leaving current-less state. PC20070604.8 Figure 13: Timing Diagram of SLA-pin 8.6 Warning, Error Detection and Diagnostics Feedback 8.6.1. Thermal Warning and Shutdown When junction temperature rises above TTW, the thermal warning bit <TW> is set (Table 27: SPI Status Register 0). If junction temperature increases above thermal shutdown level, then the circuit goes in “thermal shutdown” mode (<TSD>) and all driver transistors are disabled (high impedance) (Table 29: SPI Status Register 2). The conditions to reset flag <TSD> is to be at a temperature lower than TTW and to clear the <TSD> flag by reading it using any SPI read command. 8.6.2. Over-Current Detection The over-current detection circuit monitors the load current in each activated output stage. If the load current exceeds the over-current detection threshold, then the over-current flag is set and the drivers are switched off to reduce the power dissipation and to protect the integrated circuit. Each driver transistor has an individual detection bit in the Table 28: SPI Status Register 1 and Table 29: SPI Status Register 2 (<OVCXij> and <OVCYij>). Error condition is latched and the microcontroller needs to clean the status bits to reactivate the drivers. AMI Semiconductor – June 2007, M-20683-001 www.amis.com 14 AMIS-30521 Micro-stepping Motor Driver Data Sheet 8.6.3. Open Coil Detection Open coil detection is based on the observation of 100 percent duty cycle of the PWM regulator. If in a coil 100 percent duty cycle is detected for longer than 200ms then the related driver transistors are disabled (high-impedance) and an appropriate bit in the SPI status register is set (<OPENX> or <OPENY>). (Table 27: SPI Status Register 0) 8.6.4. Charge Pump Failure The charge pump is an important circuit that guarantees low Rdson for all drivers, especially for low supply voltages. If supply voltage is too low or external components are not properly connected to guarantee Rdson of the drivers, then the bit <CPFAIL> is set in the Table 27: SPI Status Register 0. Also after power-on-reset the charge pump voltage will need some time to exceed the required threshold. During that time <CPFAIL> will be set to “1”. 8.6.5. Error Output This is a digital output to flag a problem to the external microcontroller. The signal on this output is active low and the logic combination of: NOT(ERRB) = <TW> OR <TSD> OR <OVCXij> OR < OVCYij> OR <OPENi> OR <CPFAIL> 8.7 CLR pin (=Hard Reset) Logic 0 on CLR pin allows normal operation of the chip. To reset the complete digital inside AMIS-30521, the input CLR needs to be pulled to logic 1 during minimum time given by TCLR. (Table 6: AC Parameters) This reset function clears all internal registers without the need of a power-cycle. The operation of all analog circuits is depending on the reset state of the digital, charge pump remains active. Logic 0 on CLR pin resumes normal operation again. 8.8 Sleep Mode The bit <SLP> in Table 15: SPI Control Register 2 is provided to enter a so-called “sleep mode”. This mode allows reduction of currentconsumption when the motor is not in operation. The effect of sleep mode is as follows: • • • • • • • The drivers are put in HiZ All analog circuits are disabled and in low-power mode All internal registers are maintaining their logic content NXT and DIR inputs are forbidden SPI communication remains possible (slight current increase during SPI communication) Reset of chip is possible through CLR pin Oscillator and digital clocks are silent, except during SPI communication Normal operation is resumed after writing logic ‘0’ to bit <SLP>. A start-up time is needed for the charge pump to stabilize. After this time, NXT commands can be issued. AMI Semiconductor – June 2007, M-20683-001 www.amis.com 15 AMIS-30521 Micro-stepping Motor Driver Data Sheet 9.0 SPI interface The serial peripheral interface (SPI) is used to allow external microcontroller (MCU) to communicate with the device. The implemented SPI block is flexible enough to interface directly with numerous microcontrollers from several manufacturers. AMIS-30521 acts always as a slave and it can’t initiate any transmission. The operation of the device is configured and controlled by means of SPI registers, which are observable for read and/or write from the master. 9.1 SPI Transfer Format and Pin Signals During an SPI transfer, data is simultaneously transmitted (shifted out serially) and received (shifted in serially). A serial clock line (CLK) synchronizes shifting and sampling of the information on the two serial data lines (DO and DI). DO signal is the output from the slave, and DI signal is the output from the master. A slave select line (CSB) allows individual selection of a slave SPI device in a multipleslave system. The CSB line is active low. If AMIS-30521 is not selected, DO is in high impedance state and it does not interfere with SPI bus activities. Since AMIS-30521 always clocks data out on the falling edge and samples data in on rising edge of clock, the MCU SPI port must be configured to match this operation. SPI clock idles low between the transferred bytes. The diagram below is both a master and a slave timing diagram since CLK, DO and DI pins are directly connected between the master and the slave. 8 7 6 5 4 3 2 1 MSB 6 5 4 3 2 1 LSB 6 5 4 3 2 1 LSB CLK (Idles Low) DI (From Master) DO (From Slave) MSB (1) CSB Note (1): MSB of data stored on the new address (see Transfer packet). The internal data-out shift buffer of AMIS-30521 is updated with new content only at the last (every eighth) falling edge of the CLK signal. Figure 14: Timing Diagram of an SPI Transfer 9.2 Transfer Packet Serial data transfer is assumed to follow MSB first rule. The transfer packet contains one or more 8-bit characters (bytes). MSB LSB Command and Address Cmd2 Cmd1 Cmd0 Addr4 Addr3 Addr2 Addr1 Addr0 MSB LSB Data byte Data7 - Data0 The first byte contains command and SPI Register address and will be sent upfront of the packet to indicate to AMIS-30521 the chosen register and the type of operation. There are two possible commands for the master in normal operation mode of AMIS-30521: • READ from SPI register: Cmd2 = 0 • WRITE to SPI register: Cmd2 = 1 AMI Semiconductor – June 2007, M-20683-001 www.amis.com 16 AMIS-30521 Micro-stepping Motor Driver Data Sheet WRITE command executed for read-only register will not affect the register and the device operation. In case of READ command the data byte is optional. If a byte is transmitted after READ command it is also interpreted as a command (see examples below). If the master reads data from a status register (SPI Status Register Description), then the most significant bit (Data 7) represents a parity of Data6 to Data0 bits. If the number of logical ones in the data is odd then the parity bit equals 1. If the number of logical ones is even then the parity bit equals 0. This is a simple mechanism to protect against noise and to verify the correct transmission operation and the consistency of the status data. If a parity check error occurs, the master could initiate an additional READ command to obtain the status again. The CSB line is active low and may remain low between each successive READ commands. There is only one exception of this rule: if error condition is latched in status register (SPI Status Register Description) and the master needs to clear the status bits then exactly after READ command of a latched status register CSB line should go from low to high. This is explained in the following note: Note: The status registers and ERRB pin (SPI Status Register Description) are updated by the internal system clock only when CSB line is high. It is recommended to keep the CSB line high always when the SPI bus is idle. If the master sends WRITE command, then the incoming data will be stored in the corresponding register only if CSB goes from low to high. The writing to the register is only enabled if exactly 16 bits are transmitted within one transfer packet. If more or less clock pulses are counted within one packet the complete packet is ignored. AMIS-30521 responds on every incoming byte by shifting out the data stored on the last address sent via the bus. After POR the initial address is unknown. The following examples illustrate communication sessions between the master and AMIS-30521: CSB Master 305xx AddrA Read AddrB Write DataC AddrB Read AddrB Read Last Addr Data AddrA DataA AddrB DataB AddrB DataB AddrB DataC DataC is written in AddrB on rising edge of CSB Figure 15: Example SPI Transfer In this example, the master reads first the status from AddrA and then writes control byte in AddrB. After write operation the master could initiate a read back command in order to verify the data just written. Note that the first verification read operation returns the old content of AddrB, the second read command returns the new AddrB data. Note: The internal data out shift buffer of AMIS-30521 is updated with the content of the selected SPI register only at the last (every eighth) falling edge of the CLK signal (SPI Transfer Format and Pin Signals). As a result, new data for transmission cannot be written to the shift buffer at the beginning of the transfer packet and the first byte shifted out might represent old data. This rule also applies when the master device wants to initiate an SPI transfer to read the status registers. Because the internal system clock updates the status registers only when CSB line is high, the first read out byte might represent an old status (see Figure 16 and Figure 17 below). AMI Semiconductor – June 2007, M-20683-001 www.amis.com 17 AMIS-30521 Micro-stepping Motor Driver Data Sheet Status Registers are updated CSB Master Status R Read 305xx Last Data Add Status R Read Status R Read Status R Read Status StatusA Status StatusA Status StatusB Figure 16: Example SPI Transfer The last case illustrates data polling from several registers of the SPI register bank: CSB A d d rA R ead M a s te r 305xx A d d rB R ead Last A ddr D a ta A d d rA D a ta A A d d rC R ead A d d rB D a ta B Figure 17: Example SPI Transfer AMI Semiconductor – June 2007, M-20683-001 www.amis.com 18 AMIS-30521 Micro-stepping Motor Driver Data Sheet 9.3 SPI Control Registers All SPI control registers have Read/Write access and default to "0" after power-on or hard reset. Table 13: SPI Control Register 0 Control Register 0 (CR0) Address Content Bit 7 Bit 6 Access R/W R/W 01h Reset 0 0 Data SM[2:0] Where: R/W Reset: SM[2:0]: CUR[4:0]: Bit 5 R/W 0 Structure Bit 4 Bit 3 R/W R/W 0 0 CUR[4:0] Bit 2 Bit 1 Bit 0 R/W 0 R/W 0 R/W 0 Read and Write access Status after power-On or hard reset Step mode Current amplitude Table 14: SPI Control Register 1 Address 02h Content Access Reset Data Where: R/W Reset:: DIRCTRL NXTP PWMF PWMJ EMC[1:0] Bit 7 R/W 0 DIRCTRL Control Register 1 (CR1) Structure Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 R/W 0 NXTP R/W 0 PWMJ R/W R/W 0 0 EMC[1:0] Control Register 2 (CR2) Structure Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 R/W 0 SLP R/W 0 - R/W 0 - R/W 0 - R/W 0 - R/W 0 - R/W 0 PWMF Bit 0 Read and Write access Status after power-on or hard reset Direction control NEXT polarity PWM frequency PWM jitter EMC slope control Table 15: SPI Control Register 2 Address 03h Content Access Reset Data Where: R/W Reset: MOTEN SLP SLAG SLAT Bit 7 R/W 0 MOTEN R/W 0 SLAG R/W 0 SLAT R/W 0 - Read and Write access Status after power-On or hard reset Motor enable Sleep Speed load angle gain Speed load angle transparency Table 16: SPI Control Parameter Overview SLAT Symbol Description SLAT Status <SLAT> = 0 <SLAT> = 1 Speed Load Angle Transparency bit AMI Semiconductor – June 2007, M-20683-001 www.amis.com 19 Behavior SLA is transparent SLA is NOT transparent AMIS-30521 Micro-stepping Motor Driver Table 17: SPI Control Parameter Overview SLAG Symbol Description SLAG Speed Load Angle Gain setting Table 18: SPI Control Parameter Overview PWMF Symbol Description PWMF Enables doubling of the PWM frequency Enables jittery PWM CUR[4:0] Enables sleep mode Behavior Jitter disabled Jitter enabled Behavior Active mode Sleep mode Status Value Drivers disabled Drivers enabled <MOTEN> = 0 <MOTEN> = 1 Activates the motor driver outputs Status <DIR> = 0 Controls the direction of rotation (in combination with logic level on input DIR) <DIR> = 1 <DIRCTRL> = 0 <DIRCTRL> = 1 <DIRCTRL> = 0 <DIRCTRL> = 1 Status <NXTP> = 0 <NXTP> = 1 Selects if NXT triggers on rising or falling edge Value CW motion CCW motion CCW motion CW motion Value Trigger on rising edge Trigger on falling edge Selects IMCmax peak. This is the peak or amplitude of the regulated current waveform in the motor coils. Table 24: SPI Control Parameter Overview CUR[4:0] CUR[4:0] Index Current (mA) 0 0 0 0 0 0 30 1 0 0 0 0 1 60 2 0 0 0 1 0 90 3 0 0 0 1 1 100 4 0 0 1 0 0 110 5 0 0 1 0 1 120 6 0 0 1 1 0 135 7 0 0 1 1 1 150 8 0 1 0 0 0 160 9 0 1 0 0 1 180 A 0 1 0 1 0 200 B 0 1 0 1 1 220 C 0 1 1 0 0 240 D 0 1 1 0 1 270 E 0 1 1 1 0 300 F 0 1 1 1 1 325 Index 10 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1E 1F AMI Semiconductor – June 2007, M-20683-001 www.amis.com Value fPWM = 22.8kHz fPWM = 45.6kHz <SLP> = 0 <SLP> = 1 Table 23: SPI Control Parameter Overview NXTP Symbol Description NXTP Status Status Table 22: SPI Control Parameter Overview DIRCTRL Symbol Description DIRCTRL Gain = 0.5 Gain = 0.25 <PWMJ> = 0 <PWMJ> = 1 Table 21: SPI Control Parameter Overview MOTEN Symbol Description MOTEN Value <SLAG> = 0 <SLAG> = 1 Status Table 20: SPI Control Parameter Overview SLP Symbol Description SLP Status <PWMF> = 0 <PWMF> = 1 Table 19: SPI Control Parameter Overview PWMJ Symbol Description PWMJ Data Sheet 20 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 CUR[4:0] 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 Current (mA) 365 400 440 485 535 595 650 725 800 885 970 1070 1190 1300 1450 1600 AMIS-30521 Micro-stepping Motor Driver Data Sheet Adjusts the dV/dt of the PWM voltage slopes on the motor pins. EMC[1:0] Table 25: SPI Control Parameter Overview EMC[1:0] EMC[1:0] Index Slope (V/µs) 0 0 0 150 1 0 1 100 2 1 0 50 3 1 1 25 Remark Turn-on and turn-off voltage slope 10% to 90% “ “ “ Selects the micro-stepping mode. SM[2:0] Table 26: SPI Control Parameter Overview SM[2:0] SM[2:0] Index Step Mode 1 0 0 0 0 /32 1 1 0 0 1 /16 1 2 0 1 0 /8 3 0 1 1 ¼ 4 1 0 0 ½ 5 1 0 1 ½ 6 1 1 0 Full 7 1 1 1 N/A Remark Micro-step Micro-step Micro-step Micro-step Uncompensated half-step Compensated half-step Full step For future use 9.4 SPI Status Register Description All four SPI status registers have Read Access and are default to "0" after power-on or hard reset. Table 27: SPI Status Register 0 Address 04h Content Access Reset Data Bit 7 R 0 PAR Status Register 0 (SR0) Structure Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 R 0 OPENX R 0 OPENY R 0 - R 0 - Status Register 1 (SR1) Structure Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 R 0 - R 0 - R 0 - R 0 TW R 0 CPfail Where: R Reset PAR TW Cpfail OPENX OPENY Read only mode access Status after power-pn or hard reset Parity check Thermal warning Charge pump failure Open Coil X detected Open Coil Y detected Remark: Data is not latched R 0 - Table 28: SPI Status Register 1 Address 05h Content Access Reset Data Where: R Reset PAR OVXPT OVXPB OVXNT OVXNB Remark: Bit 7 R 0 PAR R 0 OVCXPT R 0 OVCXPB R 0 OVCXNT Read only mode access Status after power-on or hard reset Parity check Over-current detected on X H-bridge: MOTXP terminal, top transistor Over-current detected on X H-bridge: MOTXP terminal, bottom transistor Over-current detected on X H-bridge: MOTXN terminal, top transistor Over-current detected on X H-bridge: MOTXN terminal, bottom transistor Data is latched AMI Semiconductor – June 2007, M-20683-001 www.amis.com R 0 OVCXNB 21 AMIS-30521 Micro-stepping Motor Driver Data Sheet Table 29: SPI Status Register 2 Address 06h Content Status Register 2 (SR2) Structure Bit 6 Bit 5 Bit 4 Bit 7 Access Reset Data R 0 PAR R 0 OVCYPT R 0 OVCYPB R 0 OVCYYNT Bit 3 Bit 2 Bit 1 Bit 0 R 0 OVCYNB R 0 TSD R 0 - R 0 - Where: R Reset PAR OVCYPT OVCYPB OVCYNT OVCYNB TSD Read only mode access Status after power-on or hard reset Parity check Over-current detected on Y H-bridge: MOTYP terminal, top transistor Over-current detected on Y H-bridge: MOTYP terminal, bottom transistor Over-current detected on Y H-bridge: MOTYN terminal, top transistor Over-current detected on Y H-bridge: MOTYN terminal, bottom transistor Thermal shutdown Remark: Data is latched Table 30: SPI Status Register 3 Address 07h Content Access Reset Data Bit 7 R 0 PAR Status Register 3 (SR3) Structure Bit 6 Bit 5 Bit 4 R 0 R 0 Where: R Reset PAR MSP[6:0] Read only mode access Status after power-pn or hard reset Parity check Translator micro-step position Remark: Data is not latched AMI Semiconductor – June 2007, M-20683-001 www.amis.com Bit 3 R R 0 0 MSP[6:0] 22 Bit 2 Bit 1 Bit 0 R 0 R 0 R 0 AMIS-30521 Micro-stepping Motor Driver Data Sheet Table 31: SPI Status Flags Overview Length (bit) Flag Mnemonic Related SPI Register Charge pump failure CPFail 1 SPI Status Register 0 Micro-step position OPEN Coil X OPEN Coil Y OVer Current on X H-bridge; MOTXN terminal; Bottom tran. OVer Current on X H-bridge; MOTXN terminal; Top transist. OVer Current on X H-bridge; MOTXP terminal; Bottom tran. OVer Current on X H-bridge; MOTXP terminal; Top transist. OVer Current on Y H-bridge; MOTYN terminal; Bottom tran. OVer Current on Y H-bridge; MOTYN terminal; Top transist. OVer Current on Y H-bridge; MOTYP terminal; Bottom tran. OVer Current on Y H-bridge; MOTYP terminal; Top transist. Thermal shutdown Thermal warning MSP[6:0] OPENX OPENY 7 1 1 SPI Status Register 0 SPI Status Register 0 SPI Status Register 0 OVCXNB 1 SPI Status Register 1 OVCXNT 1 SPI Status Register 1 OVCXPB 1 SPI Status Register 1 OVCXPT 1 SPI Status Register 1 OVCYNB 1 SPI Status Register 2 OVCYNT 1 SPI Status Register 2 OVCYPB 1 SPI Status Register 2 OVCYPT 1 SPI Status Register 2 TSD TW 1 1 SPI Status Register 2 SPI Status Register 0 AMI Semiconductor – June 2007, M-20683-001 www.amis.com 23 Comment ‘0’ = no failure ‘1’ = failure: indicates that the charge pump does not reach the required voltage level. Note 1 Translator micro-step position ‘1’ = Open coil detected ‘1’ = Open coil detected ‘0’ = no failure ‘1’ = failure: indicates that over current is detected at bottom transistor XN-terminal ‘0’ = no failure ‘1’ = failure: indicates that over current is detected at top transistor XN-terminal ‘0’ = no failure ‘1’ = failure: indicates that over current is detected at bottom transistor XP-terminal ‘0’ = no failure ‘1’ = failure: indicates that over current is detected at top transistor XP-terminal ‘0’ = no failure ‘1’ = failure: indicates that over current is detected at bottom transistor YN-terminal ‘0’ = no failure ‘1’ = failure: indicates that over current is detected at top transistor YN-terminal ‘0’ = no failure ‘1’ = failure: indicates that over current is detected at bottom transistor YP-terminal ‘0’ = no failure ‘1’ = failure: indicates that over current is detected at top transistor YP-terminal Reset State ‘0’ ‘0000000’ ‘0’ ‘0’ ‘0’ ‘0’ ‘0’ ‘0’ ‘0’ ‘0’ ‘0’ ‘0’ ‘0’ ‘0’ AMIS-30521 Micro-stepping Motor Driver Data Sheet 10.0 Package Outline Dimensions: Dim Min A 0.8 A1 0 A2 0.576 A3 b 0.25 C 0.24 D D1 E E1 e J 5.37 K 5.37 L 0.35 P R 2.185 Notes : Nom 0.02 0.615 0.203 0.3 0.42 7 6.75 7 6.75 0.65 5.47 5.47 0.4 45 Max 0.9 0.05 0.654 0.35 0.6 5.57 5.57 0.45 2.385 Unit mm mm mm mm mm mm mm mm mm mm mm mm mm mm Degree mm 2 Dimensions apply to plated terminal and are measured between 0.2 and 0.25 mm from terminal tip. 3 The pin #1 indication must be placed on the top surface of the package by using indentation mark or other feature of package body. 4 Exact shape and size of this feature is optional 5 Applied for exposed pad and terminals. Exclude embedding part of exposed pad from measuring. 6 Applied only to terminals 7 Exact shape of each corner is optional 7x7 NQFP Figure 18: NQFP-32: No Lead Quad Flat Pack; 32 Pins; Body Size 7x7mm (AMIS Reference: NQFP-32) AMI Semiconductor – June 2007, M-20683-001 www.amis.com 24 AMIS-30521 Micro-stepping Motor Driver Data Sheet 11.0 Soldering 11.1 Introduction to Soldering Surface Mount Packages This text gives a very brief insight to a complex technology. A more in-depth account of soldering ICs can be found in the AMIS “Data Handbook IC26; Integrated Circuit Packages” (document order number 9398 652 90011). There is no soldering method that is ideal for all surface mount IC packages. Wave soldering is not always suitable for surface mount ICs, or for printed-circuit boards (PCB) with high population densities. In these situations re-flow soldering is often used. 11.2 Re-flow Soldering Re-flow soldering requires solder paste (a suspension of fine solder particles, flux and binding agent) to be applied to the PCB by screen printing, stencilling or pressure-syringe dispensing before package placement. Several methods exist for re-flowing; for example, infrared/convection heating in a conveyor type oven. Throughput times (preheating, soldering and cooling) vary between 100 and 200 seconds depending on the heating method. Typical reflow peak temperatures range from 215 to 260°C. The top-surface temperature of the packages should preferably be kept below 230°C. 11.3 Wave Soldering Conventional single wave soldering is not recommended for surface mount devices (SMDs) or PCBs with a high component density, as solder bridging and non-wetting can present major problems. To overcome these problems, the double-wave soldering method was specifically developed. If wave soldering is used the following conditions must be observed for optimal results: • Use a double-wave soldering method comprising a turbulent wave with high upward pressure followed by a smooth laminar wave. • For packages with leads on two sides and a pitch (e): •Larger than or equal to 1.27mm, the footprint longitudinal axis is preferred to be parallel to the transport direction of the PCB; •Smaller than 1.27mm, the footprint longitudinal axis must be parallel to the transport direction of the PCB. The footprint must incorporate solder thieves at the downstream end. • For packages with leads on four sides, the footprint must be placed at a 45º angle to the transport direction of the PCB. The footprint must incorporate solder thieves downstream and at the side corners. During placement and before soldering, the package must be fixed with a droplet of adhesive. The adhesive can be applied by screen printing, pin transfer or syringe dispensing. The package can be soldered after the adhesive is cured. Typical dwell time is four seconds at 250°C. A mildly-activated flux will eliminate the need for removal of corrosive residues in most applications. 11.4 Manual Soldering Fix the component by first soldering two diagonally-opposite end leads. Use a low voltage (24V or less) soldering iron applied to the flat part of the lead. Contact time must be limited to 10 seconds at up to 300°C. When using a dedicated tool, all other leads can be soldered in one operation within two to five seconds between 270 and 320°C. Table 32: Soldering Process Soldering Method Package Wave BGA, SQFP HLQFP, HSQFP, HSOP, HTSSOP, SMS (3) PLCC , SO, SOJ LQFP, QFP, TQFP SSOP, TSSOP, VSO Notes: (1) (2) (3) (4) (5) Not suitable (2) Not suitable Suitable (3) (4) Not recommended (5) Not recommended Re-flow (1) Suitable Suitable Suitable Suitable Suitable All surface mount (SMD) packages are moisture sensitive. Depending upon the moisture content, the maximum temperature (with respect to time) and body size of the package, there is a risk that internal or external package cracks may occur due to vaporization of the moisture in them (the so called popcorn effect). For details, refer to the drypack information in the “Data Handbook IC26; Integrated Circuit Packages; Section: Packing Methods.” These packages are not suitable for wave soldering as a solder joint between the PCB and heatsink (at bottom version) can not be achieved, and as solder may stick to the heatsink (on top version). If wave soldering is considered, then the package must be placed at a 45° angle to the solder wave direction. The package footprint must incorporate solder thieves downstream and at the side corners. Wave soldering is only suitable for LQFP, TQFP and QFP packages with a pitch (e) equal to or larger than 0.8mm; it is definitely not suitable for packages with a pitch (e) equal to or smaller than 0.65mm. Wave soldering is only suitable for SSOP and TSSOP packages with a pitch (e) equal to or larger than 0.65mm; it is definitely not suitable for packages with a pitch (e) equal to or smaller than 0.5mm. AMI Semiconductor – June 2007, M-20683-001 www.amis.com 25 AMIS-30521 Micro-stepping Motor Driver Data Sheet 12.0 Company or Product Inquiries For more information about AMI Semiconductor’s products or services visit our Web site at http://www.amis.com. 13.0 Document History Table 33: Revision History Version Date 0.1 18-jan-06 0.2 24-jan-06 0.3 9-feb-06 0.4 9-mar-06 0.5 0.6 1.0 22-mar-06 24-may-06 2-june-07 Modification initial draft draft : changed PWM description, added SLA pin description, changed POR and WD paragraphs. CEN->CENB, NXT pin timing, SPI I/F, 30521 section 8.5, 8.6,8.7, 30522 section 8.4,8.5 updated pin-out & added drawing, CENB->CLR, ERR->ERRB, removed SWP bits, updated SPI bits, added package details Renamed CS -> CSB, Swapped pins CLR and CSB Updated pins, AC&DC tables, SLA specs, SM[2:0] decoding Final version Devices sold by AMIS are covered by the warranty and patent indemnification provisions appearing in its Terms of Sale only. AMIS makes no warranty, express, statutory, implied or by description, regarding the information set forth herein or regarding the freedom of the described devices from patent infringement. AMIS makes no warranty of merchantability or fitness for any purposes. AMIS reserves the right to discontinue production and change specifications and prices at any time and without notice. AMI Semiconductor's products are intended for use in commercial applications. Applications requiring extended temperature range, unusual environmental requirements, or high reliability applications, such as military, medical life-support or life-sustaining equipment, are specifically not recommended without additional processing by AMIS for such applications. Copyright ©2007 AMI Semiconductor, Inc. AMI Semiconductor – June 2007, M-20683-001 www.amis.com 26