ADS7852: Recovering from power glitch

Hi Kim,

Welcome to our e2e forum!  Unfortunately there is no means to do an external reset of the ADS7852.  If you need to completely cycle power, it does sound like an SCR latch up situation.  I suspect the analog inputs are still applied during this power glitch, is that the case?  Can you share a schematic?  Perhaps there is something that can be done to prevent the lockup to begin with.

Hi Tom,

All input channels are connected to sensors, also during the glitch.

This is a schematic of ADC:

This is a schematic of one of the inputs:

Here is a scope image of a glitch, where it goes into the latched up situation.

If you have any suggestions it will be great. Thanks.

Hi Kim,

So, from the scope, it looks like the clock stopped which is what caused the ADS7852 to stop converting.  Is the ADS7852 holding the clock low when you try to re-start?  

Hi Tom,

After the main processor is restarted, it sends out the clock pulses again, but the ADC is keeping the BUSY pin low. So the processor just keeps waiting for the ADC to get ready. But I was thinking if it could be possible to force it somehow. Can it perhaps be forced into sleep mode and back again ?

Hi Kim,

Can you send me the sequence you try with the ADS7852 when trying to recover from the glitch?