Hi everyone,
I am writing to you because I have a problem with a new project that I am developing. following the instructions in the datasheet I made my circuit, but I have a problem, the LEDs on my LCD panel are flashing, the inductor and diode D1 heat up a lot.
The power supply voltage is 12V and below the resistense and capacitor values.
The strange thing is that if I bring the power supply voltage to 13.3V the defect disappears and the LEDs stay on normally, and the inductor and the diode heat up less than before.
Below are the waveforms of Vout and OVP in the presence of the defect and after increasing the input voltage.
I ask you for support in order to solve the problem when the Vin is 12V.
Thanks
R2 = 162kOHM
R6 = 61,6kOHM
R5 = 301kOHM
R4 = 59,2 KOHM
C4 = 15nF
C5 = 270pF
Vout (with Vin 12V)
OVP (with Vin 12V)
Vout (with Vin 13.3V)
OVP (with Vin 13.3V)