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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: 6097     Entry time: Fri Dec 9 17:08:41 2011     Reply to this: 6099
Author: Jenne 
Type: Update 
Category: RF System 
Subject: Lots of current used in Rich's demod box 

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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