3V is sufficient to turn on any LED, but is within its reverse break down voltage rating (that is why I did not use the common 9V battery). Short circuit current is approx. 30mA. I used a 3V lithium ...

The use of current regulator in a LED tester is shown in this project which will allow determining the exact voltage and current to supply a LED. Testing a LED comes in two ways. First is by plugging ...

The simple Diode and LED Tester presented here costs under £5 to build (including all components, the battery and a cheap case) and will indicate the polarity of almost all types of LED and other ...

LEDs measured on the test bench can produce different photometric and color results in actual operation mounted on the PC board. Also, measuring slight color and flux differences between discrete LEDs ...