TPS82150: Generating a negative 5V from negative 15V

Giles Hutchison

Part Number: TPS82150

I was planning to use two TPS82150 devices to generate +/-5V from +/-15V, and have been looking for an application note to generate negative 5V from my negative 15V rail.

I have seen the example Inverting Power Supply Schematic in Figure 30, but this doesn't work for me as +15V to -5V exceeds maximum supply voltage, and it is preferred that I use the -15V rail.

I just wondered if I was missing a simple solution?

over 6 years ago

0 Chris Glaser over 6 years ago

TI__Guru*** 147670 points

Hi Giles,

Do you have a +/-15V in and need +/-5V out? How much current do you need?

Usually, customers would take the +15V to +5V. The negative -5V rail might be made in different ways, depending on how much current is needed.

This FAQ describes how to connect any buck to make -5V from -15V: e2e.ti.com/.../2494.tps62110-as-negative-to-negative-buck

Or this reference design makes -5V from +5V: www.ti.com/.../tida-01457

0 Giles Hutchison over 6 years ago in reply to Chris Glaser

Prodigy 240 points

Thanks for the reply Chris.

As you suggested, I ended up generating -5V from +5, using a TPS82150SIL and the application note in the data sheet.

Kind regards

Giles

0 Chris Glaser over 6 years ago in reply to Giles Hutchison

TI__Guru*** 147670 points

Great! Glad it worked for you.

Because of the holidays, TI E2E™ design support forum responses will be delayed from Dec. 25 through Jan. 2. Thank you for your patience.

Power management

Power management forum

TPS82150: Generating a negative 5V from negative 15V