Hi guys,
I am trying to simulate 3 LEDs to turn on/off at a duty cycle of 33%
I supply 20 mA to each LED during a 25m period
so each 1st led will turn on at 0 to 8.3 ms
2nd led turn on at 8.4ms to 16.8 ms
3rd turns on at 16.7ms to 25.0ms
for some reason I am getting current spikes in the LEDs,
I want the current in each LED when it is on to be around 20mA
but I am getting spiking up to 120 mA
I tried to attach the snubber circuit across the mosfet to correct the spiking.
but I am unsure on how to calculate the R and C values for this.
please take a look at my LT spice simulation, thanks for reading this message.
I am trying to simulate 3 LEDs to turn on/off at a duty cycle of 33%
I supply 20 mA to each LED during a 25m period
so each 1st led will turn on at 0 to 8.3 ms
2nd led turn on at 8.4ms to 16.8 ms
3rd turns on at 16.7ms to 25.0ms
for some reason I am getting current spikes in the LEDs,
I want the current in each LED when it is on to be around 20mA
but I am getting spiking up to 120 mA
I tried to attach the snubber circuit across the mosfet to correct the spiking.
but I am unsure on how to calculate the R and C values for this.
please take a look at my LT spice simulation, thanks for reading this message.
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