White led

[pier1]

Hello all,

I have a constant current driver 350mA with an O/P voltage of 40 Vdc, I want to know a way to test the driver without the leds.

 

[Hero999]

It depends on whether it can withstand a short circuit or not.

Please post a schematic.

An easy way is to connect a 100R power resistor and measure the voltage, it should be 35V.

You might be able to get away with a 10R resistor or even just measuring the current with a meter but it depends on the power supply.

 

[pier1]

I dont have a schematic because I bought it from an electronic store, The store owner told me that it could withstand Short ckt. I dont know how far its true. I think I would try the 100ohm power resistor.

 

[Hero999]

The resistor needs to be rated for at least 5W and don't leave it connected for very long - the power dissipation will be 0.352*100 = 12.25W which is much higher than the maximum rating but will be fine, as long as it's only connected for a few seconds and a large heatsink is used.