It is a bipolar microstepper motorPulse width modulationDesigned for (PWM) current control, the A3992 is capable of continuously output current up to 1.5 amps and operates at 50 volts. Internal fixed downtime pulse-width modulation (PWM) current control is available through a serial interface to control the timing current and can be operated in low, fast, and mixed 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 allows for asynchronous progress, including torque control for microstep to full step drives. The load current is set in 1.56% of the maximum increment.
Synchronous rectification circuitry allows load current to flow through the low RDS(on) of the DMOS output driver during current decay. This feature eliminates the need for external clamping diodes in most applications, saving cost and external component count while minimizing power consumption.
Internal current protection includes short-to-ground, short-circuit load, thermal shutdown due to hysteresis, and crossover current protection. No special power-on sequencing is required.
The A3992 is available in an ultra-thin (1.2 mm, maximum height), 24-pin TSSOP (suffix LP) with exposed heat shield disc, and a 24-pin plastic DIP package with two copper batwing blades (suffix B). The exposed heat shield disc on the LP is below ground potential and does not require electrical insulation. Both packages are lead (Pb) free and feature 100% matte tin leadframe plating.
- 1.5 amps at 50 volts continuous output rate
- Low RDS(on)DMOS output driver
- Short-to-ground protection
- Load short-circuit protection
- Microsteps are optimized with a 6-bit linear DAC
- Programmable mixed, fast and slow current attenuation modes
- 4 MHz internal oscillator with digital timing
- The serial interface controls the chip function
- Synchronous rectification for low power dissipation
- Internal undervoltage lockout (UVLO) and thermal power-off circuitry
- Crossover current protection
- Input compatible with 5 or 3.3 volt control signals
- Sleep and idle mode