Ordering number : ENA1685 LV8711T Bi-CMOS LSI PWM Constant-Current Control Stepping Motor Driver http://onsemi.com Overview The LV8711T is a PWM constant-current control stepping motor driver. Features • Two circuits of PWM constant-current control H-bridge drivers incorporated • Control of the stepping motor to 1-2 phase excitations possible • Reference voltage output: 1.0V • Short circuit protection circuit incorporated • Abnormal condition warning output pin incorporated • Upper and lower regenerative diodes incorporated •Thermal shutdown circuit incorporated Specifications Absolute Maximum Ratings at Ta = 25°C Parameter Symbol Motor supply voltage VM max Logic supply voltage VCC max Conditions Ratings Unit 18 V 6 V 6 V Logic input voltage VIN Output peak current IO peak Per ch, tw ≤ 10ms, duty 20% 1.0 A Output continuous current IO max Per ch 800 mA Allowable power dissipation Pd max * 1.45 W Operating temperature Topr -20 to +85 °C Storage temperature Tstg -55 to +150 °C * Specified circuit board : 57.0mm×57.0mm×1.7mm, glass epoxy printed circuit board. Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability. Semiconductor Components Industries, LLC, 2013 June, 2013 33110 SY 20100310-S00001 No.A1685-1/12 LV8711T Recommended Operating Ratings at Ta = 25°C Parameter Motor supply voltage range Symbol Conditions Ratings VM Logic supply voltage range VCC Logic input voltage range VIN VREF input voltage range VREF Unit 4 to 16 V 2.7 to 5.5 V -0.3 to VCC+0.3 V 0 to VCC-1.8 V Electrical Characteristics at Ta = 25°C, VM = 12V, VCC = 3.3, VREF = 1.0V Parameter Symbol Conditions Ratings min typ Unit max General Standby mode current drain Current drain IMstn PS = “L”, no load 1 μA ICCstn PS = “L”, no load 1 μA IM PS = “H”, no load 1.0 1.5 mA ICC PS = “H”, no load 1.7 3.0 mA Thermal shutdown temperature TSD Design guarantee Thermal hysteresis width ΔTSD Design guarantee 150 180 °C 40 °C VCC low voltage cutting voltage VthVCC 2.1 2.4 2.7 V Low voltage hysteresis voltage VthHYS 100 130 160 mV VREG5 4.5 5 5.5 V Ω Reference voltage REG5 output voltage Output Output on resistance RonU IO = -800mA, Source-side 0.78 1.0 0.32 0.43 Ω 10 μA 1.0 1.2 V RonD IO = 800mA, Sink-side Output leakage current IOleak VO = 15V Diode forward voltage VD ID = -800mA Logic input Logic pin input current IINL VIN = 0.8V 4 8 12 μA IINH VIN = 3.3V 22 33 45 μA 0.8 V 1.0 1.05 V Logic high-level input voltage VINH Logic low-level input voltage VINL 2.0 V Constant-current control REG1 output voltage VREG1 0.95 μA VREF input current IREF VREF = 1.0V -0.5 Current setting reference voltage Vtatt00 VREF = 1.0V 0.192 0.200 0.208 V Vtatt01 VREF = 1.0V 0.152 0.160 0.168 V Chopping frequency CHOP pin threshold voltage CHOP pin charge/discharge current Vtatt10 VREF = 1.0V 0.092 0.100 0.108 V Vtatt11 VREF = 1.0V 0.032 0.040 0.048 V Fchop Cchop = 220pF 36 45 54 kHz VCHOPH 0.6 0.7 0.8 V VCHOPL 0.17 0.2 0.23 V 7 10 13 μA 250 400 mV Ichop Output short-circuit protection EMO pin saturation voltage VsatEMO IEMO = 1mA No.A1685-2/12 LV8711T Package Dimensions unit : mm (typ) 3260A Pd max - Ta 2.0 Allowable power dissipation, Pd max - W 6.5 0.5 6.4 13 4.4 24 12 1 0.5 0.15 0.22 1.2max 0.08 (1.0) (0.5) 1.5 1.45 1.0 0.754 0.5 Specified circuit board : 57.0 × 57.0 × 1.7mm3 glass epoxy board 0 - 20 0 20 40 60 80 100 Ambient temperature, Ta - C SANYO : TSSOP24(225mil) IN1A IN1B OUT1A RNF1 OUT1B VMM OUT2A RNF2 OUT2B PGND IN2A IN2B Pin Assignment 24 23 22 21 20 19 18 17 16 15 14 13 1 2 3 4 5 6 7 8 9 10 11 12 VM NC REG5 PS EMO VREF REG1 ATT1 ATT2 CHOP VCC GND LV8711T No.A1685-3/12 + - + - VREF REG1 VCC VM GND Standard voltage Start circuit gate for upside output voltage circuit LVS TSD + standard voltage circuit RNF1 OUT1B Output preamplifier stage OUT2B Output preamplifier stage RNF2 current switch function IN2A IN2B constant current control Output control logic VMM OUT2A PS CHOP Oscillator ATT1 ATT2 IN1A IN1B current switch function Output preamplifier stage constant current control Output control logic OUT1A Output preamplifier stage REG5 + EMO PGND LV8711T Block Diagram No.A1685-4/12 LV8711T Pin Functions Pin No. Pin Name Pin Function 8 ATT1 Energization current switching pin 1. 9 ATT2 Energization current switching pin 2 13 IN2B Channel 2 driver output control input pin. 14 IN2A Channel 2 driver output control input pin. 23 IN1B Channel 1 driver output control input pin. 24 IN1A Channel 1 driver output control input pin. Equivalent Circuit VREG5 VCC GND 4 PS Enable input pin. VCC 4 GND 16 OUT2B Channel 2 OUTB output pin. 17 RNF2 Channel 2 current sensing resistor 18 OUT2A Channel 2 OUTA output pin. 20 OUT1B Channel 1 OUTB output pin. 21 RNF1 Channel 1 current sensing resistor VM connection pin. 20 16 22 18 connection pin. 22 OUT1A Channel 1 OUTA output pin. 21 17 GND 3 REG5 Internal reference voltage output pin. VCC 3 GND Continued on next page. No.A1685-5/12 LV8711T Continued from preceding page. Pin No. 5 Pin Name EMO Pin Function Equivalent Circuit Abnormal condition warning output pin. VCC 5 SGND 6 VREF Channel 1 and 2 current setting reference voltage input pin. VCC 6 GND 7 REG1 Current setting reference voltage output pin. VREG5 7 GND 10 CHOP Chopping frequency setting capacitor connection pin. VCC GND 10 No.A1685-6/12 LV8711T Input pin function (1) Chip enable function Standby mode / operating mode of the IC are switched by setting the PS pin. In the standby-state, the IC enters a power saving mode and all logic is reset. In the standby-state, internal regulator circuit is not operative. PS Condition Low or Open Standby mode Internal regulator Standby High Operating mode Operating (2) STM output control logic Parallel input IN1A(2A) Output IN1B(2B) OUT1A(2A) OUT1B(2B) Current direction Low Low OFF OFF Output OFF High Low High Low OUTA to OUTB Low High Low High OUTB to OUTA High High Low Low Brake(DCM mode) (3) Constant-current setting The constant-current control setting consist of the VREF voltage setting and resistor (RNF) connected between RNF and ground. The current is set according to the following equation. IOUT [A] = VREF [V] / 5 / RNF [Ω] Also, the voltage applied to the VREF pin can be switched to four stages settings by the state of two inputs of the ATT1 and ATT2 pins. This function is effective for power saving when the motor holding current is applied. Attenuation function of the VREF input voltage ATT1 ATT2 Current setting reference voltage attenuation ratio Low Low 100% High Low 80% Low High 50% High High 20% The output current calculation method for using of attenuation function of the VREF input voltage is as below. IOUT = (VREF / 5) х Attenuation ratio / RNF resistance e.g. When the VREF is 1.0V and the set reference voltage is 100% [(ATT1, ATT2) = (Low, Low)] and the RNF resistance is 0.47Ω, the following output current is set. IOUT = 1.0V / 5 х 100% / 0.47Ω = 425mA In this conditions, when (ATT1, ATT2) is set to (High, High), IOUT = 425mA х 20% = 85mA Therefore, the power saving is executable by attenuation of the output current when motor holding current is supplied. (4) Setting the chopping frequency For constant-current control, chopping operation is made with the frequency determined by the external capacitor (connected to the CHOP pin). The chopping frequency to be set with the capacitor connected to the CHOP pin (pin 10) is as shown below. Chopping period: Tchop Tchop ≈ C х V х 2 / I [s] V: Threshold voltage Typ, 0.5V I : Charge / discharge current Typ. 10μA Chopping frequency: Fchop Fchop ≈ 1 / Tchop [Hz] No.A1685-7/12 LV8711T (5) Constant-current control time chart (chopping operate) In each current mode, the operation sequence is as described below: · At first of chopping cycle, the IC goes to CHARGE mode. (The Blanking section in which the CHARGE mode is forced regardless of the magnitudes of the coil current (ICOIL) and the set current (IREF) exists for 1μs.) · In Blanking section, the IC compares the coil current (ICOIL) and the set current (IREF). If the ICOIL < IREF state is existent in Blanking section. Set current Coil current Forced CHARGE section Chopping cycle Current mode CHARGE SLOW FAST Charge mode continues until ICOIL ≥ IREF. After that the IC switches to SLOW DECAY mode and then switches to FAST DECAY mode for the last about 1μs. If the ICOIL < IREF state is non-existent in Blanking section. Set current Coil current Forced CHARGE section Chopping cycle Current mode CHARGE SLOW FAST The IC switches to SLOW DECAY after Blanking section, and then switches to FAST DECAY mode for the last about 1μs. The IC repeats the above operation. No.A1685-8/12 LV8711T (6) Typical current waveform in each excitation mode 6-1) STM Drive mode Two-phase excitation (CW mode) IN1A IN1B IN2A IN2B (%) 100 IOUT1 0 -100 (%) 100 IOUT2 0 -100 1-2 phase excitation (CW mode) IN1A IN1B IN2A IN2B (%) 100 lOUT1 0 -100 (%) 100 lOUT2 0 -100 No.A1685-9/12 LV8711T 6-2) DCM Drive mode IN1A(2A) IN1B(2B) (%) 100 lOUT1(2) 0 -100 (%) CW BRAKE BRAKE OFF CCW (7) Output short-circuit protection To protect IC from damage due to short-circuit of the output caused by lightening or ground fault, the output short-circuit protection circuit to put the output in the OFF mode is incorporated. 7-1) Protective function operation (Latch method) When detecting the output short-circuit state, the short-circuit protection circuit is activated. When short-circuit state is detected ≈ 4μs (count by the internal timer), detected output is OFF at the time. Then, when the output exceeds the timer latch time counted by the internal counter, the output is ON. Still, the short circuit state is detected, the IC switches all output to stand-by mode and keep the state. This state is released by setting PS = Low (8) Abnormal condition warning output pin EMO, warning output pin of thermal shutdown circuit and the output short-circuit protection circuit, is an open-drain output. EMO outputs ON when output short-circuit is detected. When detecting the output overdrive, the EMO outputs ON. If the junction temperature goes down at the time, EMO outputs OFF automatically. (9) Recommended power-on sequence Provide a wait time of 10μs or more after VCC power supply rises before supplying VM power supply. Provide a wait time of 10μs or more after VM power supply raises before setting the PS pin High. VCC VM PS The above power-on sequence is only a recommendation, and there are no risks of damage or over current to the IC even if this sequence is not followed. No.A1685-10/12 LV8711T Application Circuit Example 1 VM IN1A 2 NC IN1B 23 3 REG5 4 PS 5 EMO 6 VREF 7 REG1 8 ATT1 RNF2 17 9 ATT2 OUT2B 16 10 CHOP PGND 15 11 VCC IN2A 14 12 GND IN2B 24 Logic input Logic input Abnomal condition sensing monitor The REG1 voltage (1V) can be used to set output current. It can connect to VREF directly or after divided with resistors. The setting range (total) is 10k‰ to 100k‰ Please refer to P.7 for details. It sets the PWM frequency. The setting range is 100pF to 500pF Please refer to P.8 for details. LV8711T It is a pull-up resistor for Abnomal condition sensing monitor. The setting range is 10k‰ to 100k‰ OUT1A 22 RNF1 21 OUT1B 20 VMM 19 It is a resistor to detect output current The setting range is 0.1‰ to 1‰ Please refer to P.7 for details. OUT2A 18 M 220pF Logic input 13 Each constant setting method for the above circuit diagram example is as follows : Current LIMIT (100%) set VREF = 1.0V (when internal regulator output is connected) ILIMIT = VREF / 5 / RNF resistance = 1.0V / 5 / 0.47Ω = 425mA Chopping frequency setting Fchop = Ichop / (Cchop × Vt × 2) = 10μA/ (220pF × 0.5V × 2) = 45 kHz No.A1685-11/12 LV8711T ON Semiconductor and the ON logo are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC owns the rights to a number of patents, trademarks, copyrights, trade secrets, and other intellectual property. A listing of SCILLC’s product/patent coverage may be accessed at www.onsemi.com/site/pdf/Patent-Marking.pdf. SCILLC reserves the right to make changes without further notice to any products herein. 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