The A3948SB/SLB is a Texas Instruments (TI) product designed for pulse-width modulated (PWM) current control of DC motors. It can output continuous current of 1.5A and operate at a voltage of 50V. There is a fixed dead zone time PWM current control timing circuit inside which can be programmed via a serial interface to operate in slow, fast, and mixed current decay modes. The A3958SB/SLB are similar devices with outputs rated to ±2A. The 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. No special power-up sequencing is required. The A3948SB/SLB is available 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.
The A3948SB and A3948SLB are DMOS full-bridge PWM motor drivers designed for pulse-width modulated (PWM) current control of DC motors. They are capable of continuous output currents up to +1.5 A and operating voltages up to 50 V. The devices feature internal fixed off-time PWM current-control timing circuitry that can be programmed via a serial interface to operate in slow, fast, and mixed current-decay modes.
| Continuous Output Current | +1.5 A |
|---|---|
| Operating Voltage | 50 V |
| Load Supply Voltage Range | 20 to 50 V |
| Logic Supply Voltage Range | 4.5 to 5.5 V |
| Output On Resistance (Source) | 550 mΩ |
| Output On Resistance (Sink) | 350 mΩ |
| Operating Temperature Range | -20°C to +85°C |
| Junction Temperature | +150°C |
| Oscillator Input Frequency | 1.8 to 6.1 MHz |
The device is supplied in a 24-pin plastic DIP with a copper batwing tab (suffix 'B') and a 24-lead plastic SOIC with a copper batwing tab (suffix 'LB').
Yes, internal synchronous rectification control circuitry is provided to reduce power dissipation during PWM operation.
The device can be programmed via a serial interface to operate in slow, fast, and mixed current-decay modes.