L9942 is an integrated stepper motor driver for bipolar stepper motors designed for automotive applications. It drives bipolar stepper motors with high-efficiency and smooth operation. Micro-stepping is the preferred mode to provide low-noise operation since this technique eliminates the effects of mechanical resonances, which can lower the motor torque. A motor stall detection capability allows position alignment without an external sensor, while its step counter is addressable via an SPI as well as by a separate input, to prevent the SPI overloading when running multiple motors simultaneously.
The L9942 is an integrated stepper motor driver designed for bipolar stepper motors, specifically targeting automotive applications such as headlamp leveling and adaptive front lighting. It supports microstepping for low-noise operation and includes features like motor stall detection and an addressable step counter via SPI.
| Motor Type | Bipolar stepper motors |
|---|---|
| Recommended Buffer Capacitor | 47 uF |
| Reference Resistor Value | 6.8 kΩ |
| Stabilization Capacitor Minimum | 100 nF |
The device is designed for automotive applications such as headlamp leveling, steerable lights, and adaptive front lighting.
It requires a buffer capacitor to absorb energy fed back to the supply voltage when the motor shuts down.
The ripple at Vs during normal motor operation should be between 5% and 10%.