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Entry  Wed Jun 10 12:46:43 2009, Stefan Ritt, Input range switch added in Version 2.1.3 Capture.png
    Reply  Tue Sep 5 03:28:52 2023, Matias Henriquez, Input range switch added in Version 2.1.3 
       Reply  Wed Sep 13 13:18:45 2023, Stefan Ritt, Input range switch added in Version 2.1.3 
Message ID: 901     Entry time: Tue Sep 5 03:28:52 2023     In reply to: 9     Reply to this: 902
Author: Matias Henriquez 
Subject: Input range switch added in Version 2.1.3 

Hello,

It is not quite clear to me yet how the input range is only determined by the front end and not the DRS4 chip. According to the datasheet, the selection of ROFS determines whether the input differential range is -0.5V to 0.5V (ROFS=1.55V) or 0V to 1V (ROFS=1.05V) or -0.05V to 0.95V (ROFS=1.1V).

As far as I understand, the input differential voltage cannot go further below -0.55V since the maximum ROFS voltage is 1.6V according to the datasheet).

Also in the DRS4 evaluation board 5.1 design, the output of the differential amplifier is AC coupled to the DRS4 chip.

I'd appreciate a lot your help.

Regards,

Matias

 

Stefan Ritt wrote:

 A new software verison for the DRS4 Evaluation Board has been has been released. Version 2.1.3 adds a switch for the input range of the DRS4 board. Once can choose between -0.5V...0.5V and 0V...1V:

Capture.png

A board firmware update is not necessary for this. It was originally planned to have even a negative range -1V...0V, but this is not possible with the current board design. People who want to record negative pulses have to use an inverter to produce positive pulses. In a future version of the board it might be possible to include this functionality since this is determined by the analog front-end and not the DRS4 chip.

 

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