Hello,
We are working on Project which require switch mode power supply 230V AC to 5V@5.5A DC.
Before testing complete circuit, we have divided circuit into sub module and test it.
- AC to DC Supply up to rectification part
- Apply & test AC from 0V to 230V using Variac and DC Part
Output - Got DC Voltage up to 350V DC when applying 230V AC
2. Assemble feedback part and Apply 3.3V Square wave from Function Generator across R14 & GND.
- Connect Resistor and LED across 3 and 4 Pin apply 5V DC.
Output - LED is blinking and check voltage across 1 & 2 it’s near to 1.2V DC.
3. Assemble MOSFET,FB1 ,D4 ,R8,R9 and R12.
- Connect Resistor and LED on Drain Part. Apply 5V DC on Drain Part. Source of MOSFET is GND.
- Apply 3.3 V Square wave on Gate of MOSFET.
Output - LED is blinking.
4. Assemble only UCC28610 part, Feedback circuit and Q1 MOSFET. Apply 5V DC externally on U3.8 (VDD Pin).
- Apply 3.3V Square wave from Function Generator across R14 & GND.
- Connect Resistor and LED across 3 and 4 Pin apply 5V DC.
Output – LED is blinking.
5. Assemble all components expect U1, U2, C8, R10, R11, R7 with Load and Without Load.
- Assemble Diode which has rating 200V@3A DC capacity in place of MOSFET U1. Not placed UCC24610.
- Apply 0V to 230V AC using Variac & check the O/P voltage.
- Here Feedback circuit is connected from Opto coupler side.
Issue- With Load@1.5A, Got output Voltage 0 to 0.6V and FB Voltage at U3.1 is 0V.
- Without Load, We got output voltage 3.26V DC instead of 5V DC across secondary side. FB Voltage at U3.1 is 0.7 V.
Kindly provide us solution for the same.
Any help in this case would be appreciated.
Regards,
Ritul Patel