I've tried measuring the VF of several LEDs thus far (3 Luxs, several 0.5W, and some 5mm) being driven by a boost driver circuit and they all seem to be lower than what they should be. I used both Fluke $400 DMMs and my cheapy Radio Shack DMM and they read about the same. All I do is probe the anode and cathode of the LED, is there something I'm missing?
I measured the VF of my Q3 that's supposed to be direct drive off a 3.6V LiIon R123A and only measured 2.9V (I'm expecting closer to 3.6V). All 0.5W LEDs I measured in several Nuwais all measure about 1.15V-1.3V running off a 1.5V battery (the same results with 5mm LEDs). All of these were with the LEDs on the driver boards being run by the driver. I can't seem to get a correct reading, or one I expect. The VF of the Lux in the Q3 should be close to 3.6V (measured the cell and it had an open voltage of 3.9V at the time). The 0.5W LEDs should have something higher than the battery voltage since the driver is a boost circuit and should boost up from the 1.2-1.5V input.
Am I doing something wrong?
Does the LED VF not measure correctly when it's in the boost circuit?
Thanks.
I measured the VF of my Q3 that's supposed to be direct drive off a 3.6V LiIon R123A and only measured 2.9V (I'm expecting closer to 3.6V). All 0.5W LEDs I measured in several Nuwais all measure about 1.15V-1.3V running off a 1.5V battery (the same results with 5mm LEDs). All of these were with the LEDs on the driver boards being run by the driver. I can't seem to get a correct reading, or one I expect. The VF of the Lux in the Q3 should be close to 3.6V (measured the cell and it had an open voltage of 3.9V at the time). The 0.5W LEDs should have something higher than the battery voltage since the driver is a boost circuit and should boost up from the 1.2-1.5V input.
Am I doing something wrong?
Does the LED VF not measure correctly when it's in the boost circuit?
Thanks.
