LM2776: Generate 5V from -5V

SimonF

Expert 3370 points

Part Number: LM2776
Other Parts Discussed in Thread: TLV431

Hi Team,

do you think it is possible to use a inverting charge pump like LM2776 to go from -5V to +5V?

Best regards,

Simon

over 8 years ago

0 Chris Glaser over 8 years ago

TI__Guru**** 150820 points

No, this would give you -10V normally.

Let me ask our boost converter team to comment.

0 SimonF over 8 years ago in reply to Chris Glaser

TI__Expert 3370 points

Hi Chris,
thank you for your help!
Would a non-inverting charge pump work instead? Or do I need a boost converter?
Best regards,
Simon

0 Chris Glaser over 8 years ago in reply to SimonF

TI__Guru**** 150820 points

You need some sort of boost.

If you have any other DC/DC or voltage in the system, we may be able to build a discrete charge pump like this:
www.powersystemsdesign.com/.../5517
e2e.ti.com/.../pumping-milliamps

0 Gavin Jin over 8 years ago in reply to Chris Glaser

TI__Intellectual 1010 points

Hi Simon,

A conceptual circuit using boost converter to generate +5V from-5V is shown below. If high accuracy of 5V is needed, it needs an external shunt regulator like TLV431 to regulate the output. What is the application and what is the output current in the application?

thanks

Gavin

0 Gavin Jin over 8 years ago in reply to Gavin Jin

TI__Intellectual 1010 points

Power management

Power management forum

LM2776: Generate 5V from -5V