----- Original Message ----- |
From: "Ian Phillips" <>
Sent: Monday, November 22, 2004 9:11 PM
Subject: RE: [piclist] Re: LED's - limits for serial wiring >
> You're right, you do have to be careful and it is usually best not to
> parallel but, I will only be paralleling series runs that will be
> resistor matched to the supply voltage.
> Seeing as the load will only be on for a short period/pulsed and I am
> over spec'ing there should be no heat issues....Never say never though.
With the LEDs I'm driving with PWM, I just have a 2R2 resistor for each
group of six. Even though the current through the LEDs is 250 mA, the input
current is about 10 mA from the supply. A lot of that is taken by the MCU,
clocked at 4 MHz on the prototype. I'm using a Tiny11 AVR (25c each), BTW,
rather than a PIC. PICs are too expensive.