We found this circuit in a 1977 National Semiconductor Databook. The circuit can use other FETs like the BF245 and has an input impedance of 10 megohms. The circuit gain is unitary.
This adjustable circuit from 0 to 200 nA was found in a 90's EDN. The components can still be...
We found this circuit in 2005 Linear Technology documentation. MPOSFET is load-matched. The...
This circuit generates audio tones in a speaker with controlled frequency and volume. The...