I am using AD8429 (gain = 1000 )to make biopotential measurements. As I use AC coupled inputs, I add a resistor to ground as discussed in the datasheet. I also compare the measurements using a CMOS front-end commercial biopotential amplifier.
I am going to choose the AD8429 in my circuit design, the frequency of the signal is 400K, and the bandwidth is 80K, the gain is about 10. I found there is no gain bandwidth product of operational amplifier AD8429 in the datasheet. can you tell…
This Time I have no question, but I want to congratulate AD for being able to build the best instrumentation amplifier one can get - AD8429!
I just have tested it with gain of 6000 and the inputs clamped together.This amplifier is really awsome!
During the tests, most of time, I was using the same gain resistor 249 Ohm on AD8429 and AD8421. So under the circuit same condition (even gain will be some different), AD8421 has spikes while AD8429 does not.
A little more information for other people facing a similar problem. I was able to get my output noise measurement down to 162 nV/rtHz ( I had some extra resistance at the input that wasnt exactly matching the circuit above).
I also noticed the datasheet…
Thanks for the prompt response and also for the tip on the AD8429. This could be worth considering.
My last idea is to use schottky's to isolate the supply pins for the AD8429. Input pin current would only
flow to AD8429, so it would not exceed Iq .
In the attached drawing, there is a bypass capacitor between the supply pins. It should really…
I build diff-to-single conversion using AD8429: but the output seems to be negative shifted.
The outputs are great!
Thanks for your reply!!