hi Pete,
Your having a late night....
Problem with the Darlington being driven by a 5V signal source is that its not possible to get at the emitter more than [5V - Vbe] drop, about 5V -1.4V = 3.6 across the LED's.
Ref: my edit in post #4
EDIT:
This is a darlington option using a NPN type, note the led's are ON when the picaxe output is low.
This will give ~ 10.5V across the leds.
Your having a late night....
Problem with the Darlington being driven by a 5V signal source is that its not possible to get at the emitter more than [5V - Vbe] drop, about 5V -1.4V = 3.6 across the LED's.
Ref: my edit in post #4
EDIT:
This is a darlington option using a NPN type, note the led's are ON when the picaxe output is low.
This will give ~ 10.5V across the leds.
Attachments
Last edited: