Power LED Pulse Driver

438

07:34:17

running a 4W LED from a 1 volt source by pulsing it with back emf. press button to start

the oscillator should work, I want to try it out.  the transistor base current comes through the secondary winding, turning the transistor on.  current flows through the primary winding which builds more current through the secondary back into the base, forcing the Transistor on harder and harder until Vbe gets too low, switching it off. 

my theory there is that the resulting back emf spike should pull the voltage on the emitter negative enough to hit the high Vf of the LED, switching the LED on, and the current sink of the primary will be enough to power the LED

or it will just blow up

published 10 years ago

rich11292000

10 years ago

More than 1 amp from 1 volt? You need to add in real world resistances.

hurz

10 years ago

Rich, this depends highly on frequency and duration of pulses. LEDs can shortly much more current you might expect. But face will test and see whats happens. To many things are unclear - transformer impedance ; which BJT ; batt resistance. All these and many more (capacitances) are having impact to freq and pulse current. I m very keen to see results too :p

faceblast

10 years ago

yes I am envisioning a lot of stuffing about with winding coils and connecting them to various transistors on the bench power supply.

hurz

10 years ago

Come on, hurry up

Nyamebaalbert

10 years ago

Sup? Any feedback?

faceblast

10 years ago

life keeps getting in the way!

QDot

10 years ago

And what about real life prototype???!

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