Hi everybody,
I would like to make a current source with current output 500 uA with frequency range from 50 kHz to 200 kHz. I would like to use this source for bio-electrical analysis. So, the R_LOAD would be probably from 1 Kohm to 100 Kohm I hope. I have tried to design the improved Howland current source with TL081 amplifier, but when I use only 10 Kohm or more than 50 Khz the output current declines.
I attached my design current source.
Is there anybody to help me?
Thank you very much