LM2596: Negative supply

Vladimir Naumenkov

Expert 2970 points

Part Number: LM2596
Other Parts Discussed in Thread: LMR33620

Dear Sir,

Please, advise IC for power supply:

- Input voltage: 0V - plus 15V;

- Output voltage: 0V - minus 15 V;

- Output current max: 500 mA;

- Without galvanic isolation between input and output;

- Temperature: minus 40 to plus 60 C;

- Relatively low price;

- Minimum external components.

TIA

Sincerely,

Vladimir Naumenkov

www.agat.by

0 Frank De Stasi over 5 years ago

I think that the LM2596 is rather old and it uses voltage mode control; it may be OK but we have better options.

I would look for a converter with current mode control and maybe 1.5A or 2A. Such as LM$3602 or LMR33620.

Please also look at application note SNVA856.

0 Vladimir Naumenkov over 5 years ago in reply to Frank De Stasi

Expert 2970 points

Dear Frank, thank you

Excuse me, I have not clearly understand how to get minus 15 V out, if I have plus 15 V input (for LMR33620)?

If I understand right, input value must be more, than plus 15 V for such IC ? I have +15 V exactly and I need minus 15 V exactly, Iout = 500 mA.

TIA

Vladimir Naumenkov

0 Frank De Stasi over 5 years ago in reply to Vladimir Naumenkov

You can convert a positive 15V to a negative 15V with a buck converter. That should work.

I have attached two app notes that show how to connect the converter to get a negative 15Vout.

Power management forum