Hi
Debug between led+ and led-, using a 200Ω resistor
The pwm uses 3.3v direct power supply, and the lamp series uses a resistor instead, but the fb pin voltage is always 100mv
Could you please help confirm the cause
Thank you.
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Hi
Debug between led+ and led-, using a 200Ω resistor
The pwm uses 3.3v direct power supply, and the lamp series uses a resistor instead, but the fb pin voltage is always 100mv
Could you please help confirm the cause
Thank you.
Hi
As shown in the schematic diagram, vin is 24v input, pwm is powered on by 3.3v alone, and the output is connected to two strings of led, each string has seven led, it is supposed that the fb pin feedback voltage is 200mv under the condition of 3.3v pwm, but the actual measured value is 100mv, and the power is powered on after pwm
Below are the led parameters I used
Hi Yingjiao,
Please try first powering on the VIN, and then PWM 3.3V direct power supply and see if this helps.
Best Regards,
Steven