[Cyprian]

Hi everyone,

I am inquiring about the MicrostepPLD bipolar stepper motor driver.

Here is a link: http://www.embeddedtronics.com/microsteppld.html

Firstly I am wondering if anyone has used it and knows if the MicrostepPLD make the stepper motor produce a lot of acoustic noise (squealing and hissing) when it is being driven? I already have a stepper motor controller that utilizes the L297 and the L298N dual bridge driver combined to interface a bipolar stepper motor which produces a loud hiss and squealing sound when the motor is operated.

When I say 'loud squealing and hissing' noise I mean you hear this when the motor is being driven at a slow or medium speed. I am aware that when a stepper motor is spinning really quickly it produces a 'high pitch operational noise' but what I'm referring to is a noise you hear when the coils are being energized one at a time by the chopper circuit. Every time the coils are energized they produce a 'squeal' noise. Does the MicrostepPLD energizes the coils thus making the motor produce a 'squeal'. (you can tell when you hear this squeal noise, it sounds very annoying and u'd think the stepper motor is breaking when it is running)

Secondly does anyone know of a different stepper motor driver that is a better deal than the MicrostepPLD I can buy?

Thank you,
Cyprian

[H500]

The board is based on the lmd18245 driver. If they did a half decent layout, it should be quite silent. You could send them an email and ask.

[pminmo]

Usually the noise issue has more to do with motor time constant, chopper frequency, and off times. The noice can be chopper frequency, resulting ripple current frequncy, or spurious resulting frequencies. A board can be quiet with one motor, and quiet noisey with another that has different characteristics. For example the L297 oscillator frequency could be changed by change the oscillator components and give quieter operation.