3974 Datasheet | Allegro MicroSystems

feature will eliminate the need for external clamp diodes in most applications, saving cost and external ponent count, while minimizing power dissipation. Internal circuit protection includes thermal shutdown with hysteresis, undervoltage monitoring of VDD and the charge pump, and crossover-current protection. Special power-up sequencing is not required. The A3974SED is supplied in a 44-lead plastic PLCC with four copper batwing tabs for maximum heat dissipation. The power tabs are at ground potential and need no electrical isolation. 41 44 42 40 2 4 6 5 3 1 Data Sheet 29319.35 VBB1 NC STROBE CLOCK 7 39 NC CP2 CP1 CP GND GND GND OSC SLEEP VREG NC 8 9 CHARGE PUMP SERIAL PORT 38 37 36 35 34 33 PROGRAM PWM TIMER LOGIC DATA 10 GND 11 GND 12 GND 13 REF1 14 REF2 15 LOGIC 16 SUPPLY NC 17 VDD ÷ ÷ PROGRAM PWM TIMER LOGIC 32 31 30 29 VBB2 OUT2A 18 NC 20 GND 22 GND 24 ENABLE2 26 NC 19 SENSE2 LOAD SUPPLY2 OUT2B 28 NC 27 Dwg. PP-073 ABSOLUTE MAXIMUM RATINGS at TA = +25°C Load Supply Voltage, VBB 50 V Output Current, IOUT ±1.5 A Logic Supply Voltage, VDD 7.0 V Logic Input Voltage Range, VIN Continous -0.3 V to VDD + 0.3 V t W < 30 ns -1.0 V to VDD + 1.0 V Reference Voltage, VREF 3 V Sense Voltage (dc), VS Continous 0.5 V t W < 1 µs 2.5 V Package Power Dissipation, PD 3.9 W Operating Temperature Range, TA -20°C to +85°C Junction Temperature, TJ +150°C Storage Temperature Range, TS -55°C to +150°C Output current rating may be limited by duty cycle, ambient temperature, and heat sinking. Under any set of conditions, do not exceed the specified current rating or a...