Smoking Warning Indicator (3)

Published:2011/5/20 3:36:00 Author:Sue | Keyword: Smoking, Warning, Indicator | From:SeekIC

When the gas sensor detects no smoke, V1's breakover ability is weak because of lack of VL's infrared light. V2 then is disconnected, and IC doesn't work, BL makes no sound. When the sensor detects smoke, the smoke will have a strong scattering effect on the infrared light sent by VL, so V1 will absorb the light and have a larger working current, which makes V2 connected and IC will begin to work. Its 7 pin will output sound signal,and BLwill makea warning sound of No Smoking! after the signal is amplified by V3.



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