L9909 DC MOTOR DRIVER WITH POSITION CONTROL DESCRIPTION Oscillator. The output current at ROSC pin is mirrored to COSC pin with a proper direction according to its voltage slope. The triangular wave form at COSC pin, being compared with a threshold, defines the PWM duty cycle at the motor driver output M+ and M-. The oscillator also supplies the time base for the switch off and switch on delays and the Time Out Counter. The typical oscillator period is: Tosc = 7.04 x Rosc x Cosc MInidip ORDERING NUMBER: L9909 BLOCK DIAGRAM Vcc Vcc Current ratio = 1 : 2 2 -+ Vcc + OP1 COUN TER + START RES VR7 = 7.5% Vcc TIME OUT VR3=6.6% Vcc COMP1 Td_off switch off D ELAY VR4 = 1.5V + Tck - Td_on switch on DELAY Tck +- 150KΩ COMP7 | 5 Verr| 1 0 1 0 150KΩ 375KΩ Vcc Tck 1 COMP4 STOP START STOP DIRECTION Td_pwm pwm DELAY PWM Tck VR2=56.6%Vcc VR3=6.6%Vcc TEMP. SENSE VR5 = 6.6% Vcc over temp. DRIVE R CONTROL OFF OFF Td_ov_2 (1ms) Vcc over volt. VOLT. SENSE Vcc over volt. D ELAY2 35V Td_ov_1 (130µs) VR2 = 56.6% Vcc COMP2 over volt. DELAY 1 S FF VR3 = 6.6% Vcc Tck curr. limit R COMP3 Vcc 35V I M+ open 10V open VR2 = 56.6% Vcc VR3 = 6.6% Vcc M- Q I OP8 I curr. sense 7V VR8 = + 14.2% Vcc - Latch LATCH 16V curr. limit IN curr. limit curr. limit OSCILLATOR ROSC February 2001 GND 1/9 L9909 ABSOLUTE MAXIMUM RATINGS Symbol Parameter VCC DC battery supply voltage VCC_t Transient battery supply voltage (Figs. 4 and 5) Vin Voltage at VCOM and VFB pins Value Unit -0.3 to 55 V -0.3 to VCC_CL (*) V -0.3 to VCC +0.3 V -0.3 to 7 V VROSC Voltage AT ROSC pin VCOSC Voltage at COSC pin for VCC >16V -0.3 to16 V Voltage at COSC pin for VCC >16V -0.3 to VCC +0.3 V ±1.9 A ICC Current at V CC GND, M+ and M- ICC_t Transient Current at VCC GND (figs. 4 and 5) ±4 A Current at VFB, VCOM, COSC and ROSC ±10 mA Isig Pd Device Power Dissipation internally limited W Tj Junction Temperature -40 to 150 °C Storage and Junction Temperature -55 to 150 °C ±2000 V Tstg VESD ESD Voltage Level (Human body Model - MIL STD883C) (*) NOTE: SELF PROTECTING Stressed above those listed under”Absolute Maximum Ratings” may cause permanent damage to the device . This is a stress rating anly and functional operation of the device at any condition above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. PIN CONNECTION GND 1 8 M+ COSC 2 7 ROSC VFB 3 6 VCC VCOM 4 5 M- D99AT436 THERMAL DATA Symbol Rth j-case 2/9 Parameter Thermal resistance Junction to case (pin 1) Value Unit 70 °C/W L9909 PIN FUNCTIONS N. Name 1 GND 2 COSC Function Ground Oscillator Capacitor 3 VFB Position Feedback Voltage 4 VCOM Position Command Voltage 5 M- 6 VCC 7 ROSC 8 M+ Negative Motor Terminal Power Supply Oscillator Resistor Positive Motor Terminal ELECTRICAL CHARACTERISTICS (VCC = 7 to 18V; Tj = -40 to 85°C, unless otherwise specified.) Pin Symbol Parameter Test Condition Min. Typ. Max. Unit 10 mA 20 V POWER SUPPLY VCC ICC Quiescent Supply Current VCC_OV Over Voltage Shut Down VCC_OVdel IM+ = IM- = 0, IROSC = 100µA; VCOSC = 0 18 Over Voltage Shut Down Delay µs 130 5.5 V 70 80 V Transients of Fig.5 130 1000 µs Transients of Fig.4 1 VCC_min Minimum VCC Operating Voltage - Other Parameter may not be in spec VCC_CL Battery Supply Clamp Voltage Transients of Fig.5 Td_ov_1 Battery Supply Clamp Time Td_ov_2 Battery Supply Clamp Time ms OSCILLATOR COSC ROSC R OSC Oscillator Resistor 10 100 KΩ C OSC Oscillator Capacitor 2 100 nF TOUT Timer Run Time 16384 FOSC Oscillator Frequency ROSC 27KΩ; COSC = 10nF ROSC Vrosc Voltage at ROSC pin R OSC 27KΩ COSC ICOSC Current at COSC pin R OSC 27KΩ 430 530 TOSC 630 14.2 -20 IROSC Hz %VCC 20 % VTHCOSC High Threshold Voltage 56.6 1000 %VCC VTLCOSC Low Threshold Voltage 6.6 1000 %VCC VLINERR Voltage Ramp Linearity Error -20 20 % 3/9 L9909 ELECTRICAL CHARACTERISTICS (continued.) Pin Symbol Parameter Test Condition Min. Typ. Max. 7 10 14 Unit INPUT OUTPUT TRANSER FUNCTION VCOM VFB COSC M+ M- AV Input Output Gain VSTP Stop Motor Voltage VSTP = 2 VR4 2.5 3 3.5 V VSTR Start Error Voltage VSTR = VR7/5 1 1.5 2 %VCC Voff_c1 Comp 1 Input Offset Voltage Error Voltage when the motor starts braking -20 20 mV Ton Switch on Delay 1 2 TOSC Toff Switch off Delay 1 2 TOSC Rdiff Differential Input Impedance (see fig 3) 2VCOM − VFB Icom − IFB 100 Rcom Common Mode Input (see fig 3) VCOM + VFB Icom + IFB 50 High Side R DS IM+ = IM- = 0.3A; VCC =13.5V VCOM VFB 300 KΩ KΩ OUTPUT DRIVERS M+ M- R ON_H IM+ = IM- = 0.3A; VCC =7V RON_L Low Side RDS IM+ = IM- = 0.3A; VCC =13.5V IM+ = IM- = 0.3A; VCC =7V 1.5 Ω 1 2.6 Ω 0.6 1.5 Ω 1 2.6 Ω 1.9 A ILIM Output Current Limit for each of 4 Output Transistors Separately TR Output Rise Time 20% to 80% 20 µs TF Output Fall Time 80% to20% 20 µs VMTRAN |V(M+) - V(M-)| Output Voltage During VCC Transients Transients of figs.4 and 5 THSHDN Thermal Shutdown 1 20 Figure 2. Static Transfer Characteristic. Position Error Voltage vs. Output Voltage Perr = Verr/VCC VOUT VOUT Vcc Vcc ∆V OUT Vcc-V STP 10 -Vcc V °C 170 Figure 1. Static Transfer Characteristic. Error Voltage vs. Output Voltage ∆Verr VSTP V STR = -1.5% Vcc ∆VOUT =10 ∆Verr VSTP -10 (1+ -------) Vcc Vcc-VSTP 10 V STR = 1.5% Vcc -VSTP -Vcc 4/9 0.6 Verr Vcc -100 =10 VSTP VSTP 10 (1+ -------) Vcc -1.5 1.5 -VSTP -Vcc 100 Perr [%] L9909 Figure 3. L9909 Simplified Application Diagram Vcc Vcc IFB VFB V ERR VCOM - + M+ U709 + - V OUT M MICOM GND Figure 4. Load Dump Transient starts and the wiper voltage VFB of the feedback potentiometer moves in the direction of the input voltage VCOM, bringing the VERR voltage back to zero. When VERR becomes lower than (Vcc-VSTP)/10, a proportional control activates. The motor voltage at M+ and M- lowers with a rate factor of 10 times VERR. This motor voltage is generated, according to the motor direction, by connecting to Vcc one motor terminal and by switching the opposite one with a PWM control. When approaching the target position, at VERR=0, the motor jumps into the Rest Zone from a residual VSTP supply voltage. This control Figure 5. Inductive Switching Transient - Positive t1 Vcc Vcc T T tr tr 90% 90% Vs Vs 10% 10% Time Vs = 60V Source resistance = 0.5 Ω 1ms < tr < 10ms T = 400ms t1 = 10s Position Feedback. As shown in Figs. 3 and 6, a positive error voltage VERR = VCOM - VFBK drives the motor with a positive M+ voltage with respect to M-. A correct negative electro-mechanical feedback is established when the motor, supplied with a positive M+ voltage with respect to M-, drives the feedback potentiometerwiper to Vcc. Rest Zone. When the differential input voltage VERR crosses the zero Volts threshold, as detected by the precision comparator COMP1, the motor is braked by driving it with a zero Volts voltage. As long as VERR is kept inside the Rest Zone, ranging from -VSTR to +VSTR (see Figs. 1 and 2), no electrical stimulus is applied to the motor terminals. When in the Rest Zone M+ and M- are both driven to Vcc. Running Zone. When the input error voltage VERR goes out of the Rest Zone (see Figs. 1 and 2) the motor Vs = 100V Source resistance = 10 Ω tr = 1µs Time T = 200µs to 500µs t1 = 200ms to 500ms is suitable for motors that still run with the min. VSTP=2.5V residual supply voltage in all conditions, ensuring that the rest position is finally reached. But at the same time the max. VSTP=3.5V should not make any motor run too fast and stop far away from the set point for mechanical inertia, or even get out of the rest zone possibly starting oscillations. Time Out Counter. The Time Out is performed by a 14 Bit Counter that counts 16384 Tosc periods. When the input error voltage VERR goes out of the Rest Zone the motor and the counter start. The motor stops at the VERR zero crossing or when the Counter times out, whichever comes first. Direction Control. The motor can be driven in both direction and stopped by the timer as shown in Fig. 7. The bias voltage at VFB input sets the threshold voltage for the direction control input pin (DIR). VFB and VCOM inputs may be swapped causing the motor to reverse directions. 5/9 L9909 Figure 6. Recommended Application Diagram for Positive Control POWER Reverse Battery Protection Diode VCC M+ U709 1KΩ DC MOTOR COMMAND POTENTIOMETER VFB - 100nF + VERR 1nF 1KΩ FEEDBACK POTENTIOMETER EMI Protection Network M + - VCOM M- 1nF OSCILLATOR GROUND 100nF ROSC COSC Rosc 27KΩ Cosc 10nF 1nF GND Figure 7. Recommended Application Diagram for Direction Control POWER Reverse Battery Protection Diode VCC DIR Threshold Voltage 20KΩ EMI Protection Capacitors M+ U709 DC MOTOR VFB 1nF + DIR Protection Resistor 20KΩ GROUND - VCOM M- 1nF OSCILLATOR 100nF ROSC COSC Rosc 27KΩ Cosc 10nF Over Current Protection. The driver output pins (M+ and M-) are over current protected by 4 separate linear current limiters, one for each of the 4 power output transistors. The output drivers resume normal operation as soon as the over current is removed. Motor Over Voltage Protection. The motor is over voltage protected by switching off (to Hi-Z) the M+ and M- output drivers, when Vcc rises above the 19V typ. over voltage shut down threshold. 6/9 100nF + M 10KΩ 1nF GND Over Temperature Protection. The chip is over temperature protected by switching off (to Hi-Z) the M+ and M- output drivers. Power Supply Transient Protections. The device provides over voltage suppression for fast Vcc voltage transients (Fig. 5). The Vcc is clamped at typ. 70V by turning on all four, bridge connected, power output transistors. They are roughly subjected to equal currents and voltages for even transient energy distribution. The over voltage suppression is deactivated for slow Vcc voltage transients (Fig. 4) by raising the Vcc voltage clamp at typ. 80V. L9909 The following is the discriminating algorithm between fast and slow Vcc transients. The transient voltage clamp is normally set at 70V. If Vcc rises above the Vcc_ov=19V typ. over voltage shutdown threshold, both Td_ov_1 and Td_ov_2 timers start. When the first timer stops (after 130µs typ. delay) the clamp status is evaluated and locked. If the transient has been fast enough and the voltage clamp activated, then it remains 70V active until the second timer stops (after 1ms de- lay), then it deactivates by rising to 80V. If the transient has been slow and the voltage clamp unreached when the first timer stops, then it deactivates by rising to 80V. A new 70V clamp cycle may restart only by lowering Vcc below the 19V over voltage shutdown threshold. The VFB and VCOM input pins may connect to the Vcc or lower voltage during the power supply transients of Figs. 4 and 5. 7/9 L9909 mm inch DIM. MIN. A TYP. MIN. 3.32 TYP. MAX. 0.51 B 1.15 1.65 0.045 0.065 b 0.356 0.55 0.014 0.022 b1 0.204 0.304 0.008 0.012 E 0.020 10.92 7.95 9.75 0.430 0.313 0.384 e 2.54 0.100 e3 7.62 0.300 e4 7.62 0.300 F 6.6 0.260 I 5.08 0.200 L Z 3.18 OUTLINE AND MECHANICAL DATA 0.131 a1 D 8/9 MAX. 3.81 1.52 0.125 0.150 0.060 Minidip L9909 Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. The ST logo is a registered trademark of STMicroelectronics 2001 STMicroelectronics – Printed in Italy – All Rights Reserved STMicroelectronics GROUP OF COMPANIES Australia - Brazil - China - Finland - France - Germany - Hong Kong - India - Italy - Japan - Malaysia - Malta - Morocco Singapore - Spain - Sweden - Switzerland - United Kingdom - U.S.A. http://www.st.com 9/9