LT8361 20mA current consumption instead of microamps.

Dear EngineerZone comunity,

I have problem with low power DC-DC convertor LT8361.

I use schematic - "450kHz, 5V to 60V Input, 80V Boost Converter" page23 for the positive 5V to 96V converter and

schematic - "450kHz, 4.5V to 12V Input, –150V Output, Automotive LiDAR APD Bias Power Supply" page28 for the negative 5V to -96V converter.

Both schematics give 96V +/- 1% with loading (4.7K)  and without.

The problem is current consumption without loading.

Positive voltage converter usually has few microamps and run 10 - 50 kHz depend to inductor value,

but sometimes after power on it has 20mA and run 450 kHz. After connect/disconnect load it return to microamps.

Negative voltage convertor always has 20mA and 450kH (instead of microamps and few kHz in LTspice).

What I need change in schematic for correct start with microamps and lower frequency?

I can send more oscilloscope pictures if necessary.

Thank in advance

Alexander Sleptsov

This is inductor voltage for the positive voltage convertor.

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