Shunt FET PWM dimming

Do any of the LED drivers (e.g. MP2410 or MP2341) support high frequency dimming using a shunt FET?

Apparently there can be an issue with overshoot in output current when the FET turns on, but the technique works with a fair number of drivers.

Thanks for any insight!

Any more information I can provide here?

Doubt that the MP2410 will do it, it features short circuit protection, you need a part that will pump the full current into a short. They may not even know what you are speaking of, perhaps share a snippet of your proposed schematic.

Ah, fascinating, thanks for the reply! Do you have a favorite part (or any suggestions) for using with this technique?

Hi Elan,
Some of the LED drivers have the FET integrated,

Here is one with an external shunt FET:
MP24894 | 6V-60V input Buck WLED Controller with Hysteretic Control , DC and PWM Dimming Control | MPS (


thank you for the reply! that shows an external FET but it doesn’t appear to be a shunt FET, which is driven by PWM signal, connected in parallel with the LEDs (so essentially shorting them when active).

MPQ2489 might do it, doesn’t seem to have any smarts to get in the way of shorting the load

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