Good day,
I'm working on an automotive application using the LM3410X for powering 4x IR LED's in series.
VIN is at 5V while the total forward voltage is at about 6.4V. We have the current limit set at about 500mA.
Our issue is with the DIM Frequency control. We are not getting a linear response similar to the graph shown in the datasheet.
Our problem is more on the lower duty cycles. The average current is almost flat at a low current until it reaches a specific duty cycle, dependent on the PWM frequency.
The higher the frequency, the worse the resolution at the lower duty cycles.
Our aim is to use a PWM frequency from 20kHz above to avoid effects on our application.
Could we be doing something wrong in our design, or is this to be expected in our scenario?
I can send more information privately due to the confidentiality.
Thanks,
Jesse
