Brightness Control for small Lamps


Posted on May 21, 2012

Switch-mode driven 1.5V bulbs. This device was designed on request, to control the light intensity of four filament lamps (i.e. a ring illuminator) powered by two AA or AAA batteries, for close-up pictures with a digital camera. Obviously it can be used in other ways, at anyone`s will. Portable unit - 3V battery supply.


Brightness Control for small Lamps
Click here to download the full size of the above Circuit.

IC1 generates a 150Hz square wave having a variable duty-cycle. When the cursor of P1 is fully rotated towards D1, the output positive pulses appearing at pin 3 of IC1 are very narrow. Bulb LP1, driven by Q1, is off as the voltage across its leads is too




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

10 LEDS Audio level vumeter
Siren Circuits using timer 555
Rf-power-switch
12V voltage doubler circuit
A3952S stepper motor controller circuit design
Battery Powered Burglar Alarm
Audio/Video to UHF TV Signal Converter (Modulator)
ne555 police siren circuit
Old G.P.O. Telephone
The Hartley Oscillator
Circuit example of the LM381
CS9482 holiday lights ASIC
Remote schematic CSJ-T300B with CSJ-R02B composition



Top