LED Load Simulator

63110A/ 63113A/63115A - Chroma ATE Inc.

As shown on the V-I curve in figure 1, the LED has a forward voltage VF and a operating resistance (Rd). When using a resistor as loading, the V-I curve of the resistor is not able to simulate the V-I curve of the LED as shown in blue on figure 1. This may cause the LED driver to not start up due to the difference in V-I characteristic between the resistors and the LEDs. When using Electronic Loads, the CR and CV mode settings are set for when the LED is under stable operation and therefore, is unable to simulate turn on or PWM brightness control characteristics. This may cause the LED driver to function improperly or trigger it’s protection circuits. These testing requirements can be achieved when using a LEDs as a load; however, issues regarding the LED aging as well as different LED drivers may require different types of LEDs or a number of LEDs. This makes it inconvenient for mass production testing.