With nominal load 10mA, I am not getting regulated (10V) output voltage.
Hi Team,
I have build an offline buck converter using an LNK306 regulator. I have design it for 10V, 100mA output.
It should output a voltage of around 10V. To meet this voltage the feedback circuit consists of a 2K bias resistor and a 10K feedback resistor. I use a 10K load resistor(4mA). I have used a 10uF feedback capacitor.
With nominal load 10mA, I am not getting regulated (10V) output voltage.
PFA schematic of design.
Files
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Comments
PFA waveform across Drain and source.
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Hello NITESH FUNDE,
Upon checking of the schematic, I have noticed that you have connected capacitor C8 in reverse. The negative polarity of the capacitor should be connected to both inductor L2 and diode D8.
As for the pre-load resistor, a minimum load current of 3mA may be required to ensure output regulation. For 10 V output, 10 V / 3 mA = 3333 Ω. You can try connecting 3.3 kΩ or 3 kΩ as pre-load resistor.
Thank you.
Regards,
PI-Hiro
The output voltage more than 20V at 50V input.