This Linear Technology circuit can measure currents from 100 pA to 100 uA. The circuit is from the 80's, using a component of the era. Transistors are general purpose types.
This circuit was found in the Optoelctronics Sourcebook from Texas Instruments. The circuit has a...
With this preamplifier it is possible to use a small speaker as a microphone. The circuit is also...
This circuit can be used as a clok in digital applications. Power supply is 5-V and the pins for...