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Tue Jul 5 14:12:56 2016, varun, Update, Electronics, Antialiasing Filter Update
Sun Jul 10 18:20:39 2016, rana, Update, Electronics, Antialiasing Filter Update
Sun Jul 10 18:20:39 2016
In reply to:
Antialiasing Filter Update
Comments on the schematic:
Only the instrumentation amp should be made up of the ADA4004. Not the whitening parts.
Please think about the front panel design and make a drawing of the front and back panels. Power connectors, indicators, switches, etc. Take a look at some of our existing 1U rack electronics to see what standard arrangements are. Add a front and back panel drawing to the elog.
The whitening and anti-aliasing opamps can all be OP27 SOIC-8 for now. Later, if we need better noise performance or speed we can use faster opamps.
There should be a 3rd stage of AA. Each of the exisitng stages (U5, U6) can only be second order and we want the option to have a 6th order low pass.
There should be 100 nF decoupling capacitors on the power pins of all the single opamps.
There is a low noise power daugther board made by Ben Abbott which you can use on the DCC. It should accept the direct power connector from the back panel and supply regulated power to the board.
Take care to update the lower right hand corner info box with updated drawing version #'s and author name.
The MAX4158 is 16 years old. It may be good if you can find a newer parts so it doesn't go obsolete.
All of the R & C on the board should be sized 1206 for the SMD.
For the whitening and AA filtering stages, we want the capability to use larger size parts (e.g. the red WIMA caps that are in the blue spinny box). So you will have to use larger footprints for those.
The resistors should all be 0.1% thin film or metal film.