Published:2011/6/5 9:09:00 Author:John | Keyword: camera photometer | From:SeekIC
According to changes in light intensity, light current changes. When 3DG6 base injection current changes, the current in the collector circuit also changes after amplification. It would be reflected by the MA's meter bottom-up. And the meter reflects the light illumination.
When there is weak light, the base potential is close to 6V. 3DG6 is saturated to conduct, leading the collector current to fill the meter’s scale. When there is strong light, the base potential decreases to have a decreased injection current. And the collector current follows down to lead the meter to zero state. Darken photodiodes can make an mA full-scale meter by adjusting R1 and R3.
Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/Power_Supply_Circuit/camera_photometer_circuit.html
Print this Page | Comments | Reading(3)
Code: