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Entry  Wed Mar 3 17:36:31 2010, Hao Huan, Initialization of the Domino Circuit 
    Reply  Wed Mar 3 17:49:30 2010, Stefan Ritt, Initialization of the Domino Circuit 
Message ID: 47     Entry time: Wed Mar 3 17:49:30 2010     In reply to: 46
Author: Stefan Ritt 
Subject: Initialization of the Domino Circuit 

Hao Huan wrote:

Hi Stefan,

    I read in the datasheet that every time after power up the Domino wave in DRS4 needs to be started and stopped once to initialize the Domino circuit. However in your firmware it seems the chip immediately goes into the idle state after reset. Is that Domino circuit initialization really necessary?

    Also an aside question: in your firmware the readout process has the SRCLK sent to DRS4 only about 200ns later after RSRLOAD gets asserted instead of immediately following RSRLOAD. Is there any reason for that?

    Thanks a lot!

 

The start/stop requirement is obsolete and has been replaced by  elog:10. I need to update this in the datasheet. The delay between the RSRLOAD and the SRCLK has the following reason: On the RSRLOAD the first sampling cell is output to the chip and to the ADC. This can sometimes be a rather high swing, which needs some time to settle, and some warm-up for the output driver. But actually I never really measured it, so it's there just as a safety margin. But I would encourage you to try to reduce this time and see it the first few bins of the readout change in offset.

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