Photoelectric smoke detector circuitry

Details Photoelectric smoke detector circuitry Photoelectric smoke detector circuitry

G - Physics

08

B

340/140.1

G08B 17/10 (2006.01) G08B 17/107 (2006.01)

Patent

CA 1242256

PHOTOELECTRIC SMOKE DETECTOR CIRCUITRY Abstract of the Disclosure A photoelectric smoke detector operating on a scattered light principle. The photosensor is connected at the input of an operational amplifier, such amplifier functioning as a threshold detector, saturation pulse amplifier and fixed pulse width compensator. Another feature of the invention resides in the provision of a special RC network connected between the output of a first transistor of a flasher section or subcircuit, which provide pulse power to the light source, to the input of a second transistor in such flasher circuit. As a consequence of this arrangement, when the LED serving as the light source tends to age, with a corresponding increase in its impedance, an appropriate signal is fed back from the aforenoted output of the first transistor to the input of the second, thereby to increase the pulse width of the output signal through the LED such that it is on longer, thereby compensating for the fact that it is no longer as bright.

504721

Affiliated with

Also associated with

Rating

Photoelectric smoke detector circuitry does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Photoelectric smoke detector circuitry, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Photoelectric smoke detector circuitry will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFCA-PAI-O-1295660