This small signal amplifier circuit was found in Motorola's 1969 documentation. The FET and the transistor can be of any type and is battery powered since the consumption is very low.
The Texas Instruments TPS7A92 integrated circuit consists of a low-voltage (LDO) linear voltage...
This circuit to increase the sensitivity of instruments to 100 uA (or close to it) was found in...
This voltage controlled oscillator uses a varicap to change the frequency. Usin a 100 turns coil...