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LP55231: Issues with the external trigger on the LED DRIVER chip

TSRDM
Prodigy 690 points
Part Number: LP55231

Hello LED Driver Team:

This involves the tri color LED driver chip.

We are having issues with the external trigger on the TI LP55231 LED DRIVER chip. We tried many different methods, such as double handshaking triggers, looping/resetting to get it to work.  While the external trigger send command output meets the data sheet spec as verified on an oscilloscope on the external trigger pin, the external trigger wait on the 2nd chip does not consistently respond as expected.  Performance wise the LEDs will lose sync from each other.

 

As a work around we going to generate a 32kHz external clock to drive the clock input on 2 LED DRIVERS(LP55231) that way they will not drift from each other over time.  However, this workaround requires hardware changes, software changes and limits some of the functionality for the LED color swirl patterns.

 

Do you know of an expert on this chip that can look into if this is a known problem or if there are any solutions to the external trigger issue we are seeing?

The LPASM commands involved are:

        trigger s{e}          

        trigger w{e}

 

Thanks for any assistance!