PNP BJT constant current source

129

01:45:23

BJT-based constant current source. Toggle switch and notice LED brightness is always the same.

published 9 years ago

thebugger

9 years ago

The biasing is reversed. The resistor should be from base to ground (and much bigger 4.7kohm for instance) and the diodes should be from the power supply to base. Other than that it's fine.

johntron

9 years ago

@thebugger is that better?

thebugger

9 years ago

Yes

johntron

9 years ago

Thanks!

add comment in editor

EveryCircuit is an easy to use, highly interactive circuit simulator and schematic capture tool. Real-time circuit simulation, interactivity, and dynamic visualization make it a must have application for professionals and academia. EveryCircuit user community has collaboratively created the largest searchable library of circuit designs. EveryCircuit app runs online in popular browsers and on mobile phones and tablets, enabling you to capture design ideas and learn electronics on the go.