Designed for pulse-width modulated (PWM) current control of dc motors, the A3958SB and A3958SLB are capable of continuous output currents to ±2 A and operating voltages to 50 V. Internal fixed offtime PWM current-control timing circuitry can be programmed via a serial interface to operate in slow, fast, and mixed current-decay modes.
PHASE and ENABLE input terminals are provided for use in controlling the speed and direction of a dc motor with externally applied PWM-control signals. The ENABLE input can be programmed via the serial port to PWM the bridge in fast or slow current decay.
Internal synchronous rectification control circuitry is provided to reduce power dissipation during PWM operation. Internal circuit protection includes thermal shutdown with hysteresis, and crossover-current protection. Special power-up sequencing is not required.
The A3958SB/SLB is supplied in a choice of two power packages, a 24-pin plastic DIP with a copper batwing tab (package suffix 'B'), and a 24-pin plastic SOIC with a copper batwing tab (package suffix 'LB'). In both cases, the power tab is at ground potential and needs no electrical isolation. Each package type is available in a lead-free version (100% matte tin leadframe).
Load Supply Voltage, VBB .......................... 50 V
Output Current, IOUT ............................. ±2.0 A
Logic Supply Voltage, VDD ......................... 7.0 V
Input Voltage, VIN ............ -0.3 V to VDD + 0.3 V
Sense Voltage, VS ..................................... 0.5 V
Reference Voltage, VREF ........................... 2.7 V
Package Power Dissipation (TA = 25°C), PD
A3958SB ................................................ 3.1 W*
A3958SLB .............................................. 1.6 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 junction temperature of 150°C.
* Per SEMI G42-88 Specification.
Required Field 
