BADFLOPPY
Junior Member level 3
Hi,
I have thought and gives here schematics for LED Driver/Ballast (SwitchMode).
The concept is the following.
1. Transistor starts conducts and Fire SCR (PNP+NPN pair) till curremt limit reaches.
2. The SCR Draws base voltage down to near zero (Switch off & current through Schottky Transistor.
3. Waits for a while till base voltage increase to 0.7 and main transistor again starts conducting and current again starts increasing.
Moreover, the positive supply can be fed through a Choke coil to reduce harmonics.
A Vally fill circuit improves the load current and power factor too.
Insted of SCR monostable multivibrator, you may modify with TTl Multivibrator.
Yours remarks is required.
I have thought and gives here schematics for LED Driver/Ballast (SwitchMode).
The concept is the following.
1. Transistor starts conducts and Fire SCR (PNP+NPN pair) till curremt limit reaches.
2. The SCR Draws base voltage down to near zero (Switch off & current through Schottky Transistor.
3. Waits for a while till base voltage increase to 0.7 and main transistor again starts conducting and current again starts increasing.
Moreover, the positive supply can be fed through a Choke coil to reduce harmonics.
A Vally fill circuit improves the load current and power factor too.
Insted of SCR monostable multivibrator, you may modify with TTl Multivibrator.
Yours remarks is required.