Logarithmic light-meter circuit


Posted on Mar 28, 2013

The meter reading is directlyjproportiona! to the logarithm of the input light power. The logarithmic circuit behavior arises from the nonlineardiode pnjunction current/voltage relationship


Logarithmic light-meter circuit
Click here to download the full size of the above Circuit.

The diode in the amplifier output prevents output voltage from becoming negative (thereby pegging the meter), which may happen at low lightlevels due to amplifier bias currents. Rl adjusts the meter full-scale deflection, enabling the meter to be calibrated.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

Fiber-optic-receiver
3V Battery To 5V Dc/Dc Converter
Ir Pulse To Audio Converter Circuit
Cable Tester Circuit
SW Receiver Using ZN414
TDA2009 single power amplifier circuit diagram
Synchronous electric motor chokes down according to the stator current excitation circuit



Top