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Entry  Fri Dec 9 17:08:41 2011, Jenne, Update, RF System, Lots of current used in Rich's demod box 
    Reply  Fri Dec 9 17:44:45 2011, Koji, Update, RF System, Lots of current used in Rich's demod box 
       Reply  Fri Dec 9 20:03:57 2011, Zach, Update, RF System, Lots of current used in Rich's demod box Screen_shot_2011-12-09_at_8.00.54_PM.png
Message ID: 6101     Entry time: Fri Dec 9 20:03:57 2011     In reply to: 6099
Author: Zach 
Type: Update 
Category: RF System 
Subject: Lots of current used in Rich's demod box 

D0902745-v5 (probably the AP1053's):

Screen_shot_2011-12-09_at_8.00.54_PM.png

Quote:

Those asymmetric currents are same as what I saw with the table top +/-18V supply. If you really don't like it, there could be an option to disconnect CH3/4 in the box.

In any case, this could be a good long-run test of the demod box, couldn't it?

Quote:

I checked the power regulators on the Rich demod box (according to the schematic, D1000217).  The positive one is LM2941CT, and the negative one is LM2991T.  Both accept input voltage up to +26V or -26V respectively.  So my use of +\- 24V to be regulated down to +\- 15V isn't too crazy.  It's a little crazy, but not too crazy.  They recommend having only a 3V difference between the input and output voltages.  We don't have any 18V or 20V power supplies in the regular LSC power supply rack, so Rana suggested using the 24's. 

When I plug in and turn on the Rich box, the current on the +24V power supply goes up by about 0.8A, and the -24V supply goes up by about 0.3A.  That seems like kind of a lot.  Is that too much?  Do I need to find a better plan that involves +\- 18V?  Thoughts?

For now, the Rich box is off, just in case.

 

 

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