Hi,
My circuit is running at 109mw(See below). How much closer to its published power rating 150mw can I run on continuous use? As a caveat my ballast resistors total at 3 watts. I know its spec sheet says 150mw and I am under that but how close to max should I go -- is there a rule of thumb?
All direct measurements from circuit.
3 IR-LEDs in series
3 x 47ohm(1 watt each) ballast->141 ohms/3 watts
Vf LED = 1.47volts (measured)
measured Ia =
LED1 = .074a
LED2 = .074a
LED3 = . 075a
power = Vf x Iaf
= (1.47v) x (.074a)
= .109watts
= 109mw
My circuit is running at 109mw(See below). How much closer to its published power rating 150mw can I run on continuous use? As a caveat my ballast resistors total at 3 watts. I know its spec sheet says 150mw and I am under that but how close to max should I go -- is there a rule of thumb?
All direct measurements from circuit.
3 IR-LEDs in series
3 x 47ohm(1 watt each) ballast->141 ohms/3 watts
Vf LED = 1.47volts (measured)
measured Ia =
LED1 = .074a
LED2 = .074a
LED3 = . 075a
power = Vf x Iaf
= (1.47v) x (.074a)
= .109watts
= 109mw