Overview: AMIS-30421 Micro-Stepping Stepper
Motor Bridge Controller
Introduction The AMIS−30421 is a micro-stepping stepper motor bridge
controller for large current range bipolar applications. The chip interfaces via a SPI interface with an external controller in order to control 2 external power NMOS H−bridges. It has an on-chip voltage regulator, current sensing, self adapting PWM controller and pre-driver with smart slope control switching allowing the part to be EMC compliant with industrial and automotive applications. It uses a proprietary PWM algorithm for reliable current control.
The AMIS−30421 contains a current translation table and takes the next micro-step depending on the clock signal on the “NXT” input pin and the status of the “DIR” (direction) register or input pin. The chip provides a so-called “Speed and Load Angle” output. This allows the creation of stall detection algorithms and control loops based on load angle to adjust torque and speed.
The AMIS−30421 is implemented in a mature technology, enabling fast high voltage analog circuitry and multiple digital functionalities on the same chip. The chip is fully compatible with automotive voltage requirements.
The AMIS−30421 is easy to use and ideally suited for large current stepper motor applications in the automotive, industrial, medical and marine environment. With the on−chip voltage regulator it further reduces the BOM for mechatronic stepper applications.
