Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
Dana,
Yes, there is an inversion in the signal path, I was referencing the input to the first stage.
You studied the final amp stage, can you see why the gain can not be increased independent of the offset? The two adjustments seem to cancel each other out, the end result being the required...
Better view of amplifier circuit -
The output of U13 (rms converter) for 8uv input is 3.13vdc and for 80uv input 3.14vdc yielding output voltages at U11 of 2vdc and 3vdc
Dana, the results in your graph look correct for the circuit shown, what is needed to better understand the design flaw...
Additional information:
This design is portable device powered with 9v battery.
I posted the proto schematic for ease of understanding the final amp circuit, in the final design the pots are replaced with digital pots.
The 60hz notch filter was proto-type, in the current circuit the filter is...
Hello All!
In the attached EMG amp design the output stage allows for an offset and gain adjustment( for calibration) however there is an interaction between the two adjustments which ultimately prevents the desired output gain. The circuit design includes a preamp stage, 60hz notch filter...
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
