Hi, everyone!
I've made a LED buck-boost (BB) driver based on LM3429. It's for automotive lighting, so Vin = 9-14.5 V, LED string consist of 10 white leds. V_out is about 30V, I_out=1.3A. All components were calculated according to LM3429 datasheet for BB topology. All datasheet recommendations for PCB design were also used (I think so))). Prototype of PCB has factory execution.
During the tests there is a lot of noise on FM frequency, however driver works properly at everything else. Noise on FM radio comes from induction - it sounds different in speakers when touched. But seems like it comes from all high frequency circuit with MOSFET and LM3429.
Currently I have no idea on how to remove this noise, where could be our mistake?
Led string is separated from the LED driver into a separate cooper board, wire length is about 25-30 centimeters.
Attaching schematic, PCB, operating conditions and component values for reference. Thanks in advance!
I've made a LED buck-boost (BB) driver based on LM3429. It's for automotive lighting, so Vin = 9-14.5 V, LED string consist of 10 white leds. V_out is about 30V, I_out=1.3A. All components were calculated according to LM3429 datasheet for BB topology. All datasheet recommendations for PCB design were also used (I think so))). Prototype of PCB has factory execution.
During the tests there is a lot of noise on FM frequency, however driver works properly at everything else. Noise on FM radio comes from induction - it sounds different in speakers when touched. But seems like it comes from all high frequency circuit with MOSFET and LM3429.
Currently I have no idea on how to remove this noise, where could be our mistake?
Led string is separated from the LED driver into a separate cooper board, wire length is about 25-30 centimeters.
Attaching schematic, PCB, operating conditions and component values for reference. Thanks in advance!
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