3948

3948 A3948SLB (SOIC) CP CP2 CP1 PHASE OSC GROUND GROUND LOGIC SUPPLY ENABLE DATA CLOCK STROBE DMOS FULL-BRIDGE PWM MOTOR DRIVER 1 2 3 4 5 θ 24 23 NC 22 21 VBB 20 19 18 V DD 17 16 VREG RANGE NO CONNECTION OUTB LOAD SUPPLY GROUND GROUND SENSE OUTA NO CONNECTION MODE REF Designed for pulse-width modulated (PWM) current control of dc motors, the A3948SB and A3948SLB are capable of continuous output currents to ±1.5 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. Similar devices with outputs rated to ±2 A are available as the A3958SB/SLB. 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 A3948SB/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-lead 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...