1、中文 2723字 外文文献 （一）原文 DUAL FULL BRIDGE PROTECTED MOTOR DRIVER（ A3976） The A3976 is designed to drive both windings of a bipolar stepper motor or bidirectionally control two DC Motors. Both H-Bridges are capable of continuous output currents of up to +/- 500 mA and operating voltages to 30V. Free wheel
2、ing, substrate isolated diodes are included for output transient suppression when switching motors or other inductive loads. For each bridge the PHASE input controls load current polarity by selecting the appropriate source and sink driver pair. The ENABLE input, when held high, enables the respecti
3、ve output H-bridge. When both ENABLE pins are held low the device will enter SLEEP mode and consume less than 100mA. The 3976 is protected to ensure safe operation in harsh operating environments and was designed specifically for automotive applications. Protection circuitry will check for open or s
4、horted load, motor lead short to ground or supply, VBB overvoltage, VCC undervoltage, and thermal shutdown. If any of these conditions are detected the outputs will be disabled and fault information will be output to diagnostic pins FAULT1 and FAULT2. The 3976 is supplied in a choice of two power pa
5、ckages, a 16-lead plastic DIP with a copper batwing tab (suffix B), and a 24-lead plastic SOIC with a copper batwing tab (suffix LB). In both cases, the power tab is at ground potential and needs no electrical isolation. FEATURES （ 1） 30 V , 500 mA Continuous Output Rating （ 2） 35V Load Dump Surviva
6、l （ 3） Output Short Circuit Protection （ 4） Coded Fault Diagnostic Outputs （ 5） Low Current Standby Mode （ 6） Open Load Monitor （ 7） Low Current Standby Mode （ 8） VBB Over Voltage Shutdown （ 9） Internal Thermal Shutdown Circuitry （ 10） Internal Low Parasitic Free Wheeling Diodes （ 11） Crossover Curr
7、ent Protection ABSOLUTE MAXIMUM RATINGS at TA = +25C Operating Supply Voltage, VBB . 30 V Non-Operating Supply Voltage. 35 V Output Current, IOUT .500 mA* Logic Supply Voltage, VCC. 7.0 V Fault Output Voltage . 7.0 V Logic Input Voltage Range, VIN. -0.3 V to VCC + 0.3 V Package Power Dissipation (TA
8、 = +25C), PD A3976KLB.2.2 W A3976KB .2.9 W Operating Temperature Range, TA .-40C to +125C Junction Temperature, TJ .+150C Storage Temperature Range, TS.-55C to +150C * Output current rating may be limited by duty cycle, ambient temperature, and heat sinking. Under any set of conditions, do not excee
9、d the specified current rating or a junction temperature of 150C. PART NUMBER PACKAGE RJA RJT A3976KLB 24 Lead SOIC 56C/W 6C/W A3973KB 16 Lead DIP 43C/W 6C/W Input Logic PHASE ENABLE OUTA OUTB X 0 OFF OFF 0 1 LOW HIGH 1 1 HIGH LOW Fault Logic Fault Condition FAULT1 FAULT2 Thermal Shutdown LOW LOW Sh
10、ort to Battery or Open Load LOW HIGH Short to Ground HIGH LOW Normal Operation HIGH HIGH APPLICATION NOTES Open Lead Protection. During normal PWM operation diagnostic circuitry will look for a minimum source current level after a bridge is signalled on. Additionally, the diode flyback is monitored on the proper output. The logic will signal a fault and disable the outputs if it determines that the current is below the minimum level AND no flyback is occurring. If the inductive load is too large, the current would take too long to reach the minimal level and a
