It is a bipolar microstepper motorPulse width modulation (PWM)Designed for current control, the A3972SB is capable of continuously output current output to ±1.5 amps and operates at 50 volts. An internal fixed-off-time pulse-width modulation (PWM) current-controlled timing circuit can be programmed through a serial interface to operate in slow, fast, and mixed current attenuation modes.
The desired load current level can be set with two 6-bit linear DAC serial interfaces and a voltage reference. The 6-bit controller offers maximum flexibility in torque control in a variety of steps, from microstepping to full step drive. The load current is set in 1.56% of the maximum increment.
Synchronous rectification circuitry allows load current to pass through the low r of the DMOS output driver during current decayDS(on)Flowing. This feature eliminates the need for an external clamp diode in most applications, saving cost and external component count while minimizing power dissipation.
Internal circuit protection includes thermal shutdown with delay, transient suppression diodes, and crossover current protection. No special power-on sequencing is required.
- ± 1.5 amps, 50 volts continuous output power rating
- Low rDS (on) DMOS output driver
- Microstepping optimized with a 6-bit linear DAC
- Programmable hybrid, fast and slow current decay modes
- 4 MHz built-in oscillator for digital timing
- The serial interface controls the chip function
- Synchronous rectification enables low power dissipation
- Internal undervoltage lockout and thermal shutdown circuitry
- Crossover current protection
- Accurate 2 V reference voltage
- The inputs are compatible with 3.3 V or 5 V control signals
- Sleep and idle modes