The PCA9629 is an I²C-bus controlled low-power CMOS device that provides all the logic
and control required to drive a four phase stepper motor. PCA9629 is intended to be used
with external high current drivers to drive the motor coils. The PCA9629 supports three
stepper motor drive formats: one-phase (wave drive), two-phase, and half-step. In
addition, when used as inputs, four General Purpose Input/Outputs (GPIOs) allow sensing
of logic level output from optical interrupter modules and generate active LOW interrupt
signal on the INT pin of PCA9629. This is a useful feature in sensing home position of
motor shaft or reference for step pulses. Upon interrupt, the PCA9629 can be
programmed to automatically stop the motor or reverse the direction of rotation of motor.
Output wave train is programmable using control registers. The control registers are
programmed via the I²C-bus. Features built into the PCA9629 provide highly flexible
control of stepper motor, off-load bus controller/micro and significantly reduce I²C-bus traffic.
These include control of step size, number of steps per single command, number of full
rotations and direction of rotation. A ramp-up on start and/or ramp-down on stop is also
The PCA9629 is available in a 16-pin TSSOP package and is specified over the -40 °C to
+85 °C industrial temperature range.