Negative input negative output with buck converter

Denis Joseph1

Other Parts Discussed in Thread: LM5001

Hi, I have a requirement to generate -5V supply from -15V supply. My current requirement is 500mA. Though some material is available (referred the one in eetimes using LM5001) the design procedure of such a regulator is not mentioned. If somebody could provide some information or share circuit diagrams of similar regulators it would be of great help. The ripple limit should be 50mV.

over 10 years ago

0 Chris Glaser over 10 years ago

TI__Guru*** 147360 points

This wiki page gives one option: http://e2e.ti.com/support/power_management/non-isolated_dcdc/w/design_notes/2494.tps62110-as-negative-to-negative-buck.aspx

0 Youhao Xi over 10 years ago in reply to Chris Glaser

TI__Guru* 75695 points

The LM5001 can be configured to produce -5V from -15V. A schematic is attached below to show the concept. Follow the buck converter design procedure. The pair of pnp transistors achieves level shifted Vout sensing.

1108.LM5001 -15Vin -5VOUT.pdf.

Youhao Xi, System and Applications, TI SVA PPD-NPS

0 Timothy Hegarty over 10 years ago in reply to Youhao Xi

TI__Guru 60957 points

Hello,

Please also check out the Excel calculator here: http://www.ti.com/tool/swiftinv-calc

Regards,

Tim

Power management

Power management forum

Negative input negative output with buck converter