Adding haptic feedback to a Colibri imx8 development

Firstly, I am still in awe with how good the Toradex and surrounding developer infrastructure is. It has saved me weeks of stress and mistakes. I had a real complex job with lots of hardware and it took 10% of the usual effort; in fact I have not needed to go and scream in the carpark at all (due to a unforeseen release of the magic smoke).

I am making an application that will implement a nice touchscreen text editor, and want to add haptic feedback (i.e. a little mechanical click or buzz) each time the punter hits a key. This makes the keying activity better and means the punter will hit the screen a little softer and its likely it will last longer. We are using the resistive screen because the operator will have two pairs pairs of protective gloves on, might even use a stylus to press the keys. If I had hectares of space inside my casing I would just add a buffer amp onto the output from the module audio output to protect the module, but I am a bit tight for space.

Since I still have to just finish off the custom board I can still ask this question about hardware.

My little surface mount sounder speakers are 8ohm and sub-watt.

My question is: I just need a click or “tap” noise. Can you use a sounder with the Colibri imx8 module without a further amp ? If not, are there reference circuit suggestions that will protect the Colibri module and also provide enough volume whilst being small enough to put on a Viola design based custom board?.

Any suggestions would be brilliant.

Kind regards


According to SGT5000 codec datasheet - HP Output - 62.5 mW max, 1.02 kHz sine into 16 Ohm load at 3.3 V. So you can’t connect 8 Ohm speaker directly to Colibri pin. However you can use a small IC amplifier or even a simple transistor amplifier like this, this or that.

Thank you Alex,

I will buy it a 2056-K14.25-8OHM and amplifier IC combo.

It will soon sing out its clicky keyboard song!



Nice speaker however I haven’t found anything about amplifier in that datasheet.

I was going to say a Ti 6205A but I looked and the last time I used one was in 2015 and they are no longer a thing.

I think I will give the ON semi NCS2211 IC a go with that speaker and see if it does the trick.

Will post something on this page when I have tried it.



Found another small footprint amplifier. It requires less external components.

Really small, and costs less than a Snickers bar. Its going to be perfect.
Thanks for your help


I’d recommend to put a simple RC low pass filter between Colibri output and amplifier input to remove a high frequency digital noise, which can overload an amplifier.