---+ Cryo board analog gains

This page presents a brief circuit analysis for the cryoelectronics board, and describes some of its wrinkles.

ALERT! This topic is probably out of date and possibly incorrect. It needs review by Graeme before you should it -- please poke him.

DAC Side

DAC-side schematic

The fully differential amplifier is configured as an integrator. If we re-label the input and feedback capacitors by and , we have:

If we assume a negligible amount of current flows in the resistors above and below the RTD, we can use KCL to write:

where is the gain of the fixed-gain amplifier. Combining the two,

Or,

Now, we can express in terms of the output voltage :

Combining, we get the overall transfer function

To get the frequency response, we substitute and solve for the magnitude response. We get:

Attachments Attachments
Topic attachments
I Attachment Action Size Date Who Comment
PNGpng dac_schem.png manage 1.7 K 2009-07-15 - 16:24 GraemeSmecher  
This topic: CryoElectronics > DigitalFMux > CryoAnalogGains Topic revision: r3 - 2011-08-06 - DfmuxCollab
© 2020 Winterland Cosmology Lab, McGill University, Montréal, Québec, Canada

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ERROR: can't find dvipng at /usr/bin/dvipng
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STDERR: