TPS61080: create +/-20 V at 150mA

John Smith

Part Number: TPS61080
Other Parts Discussed in Thread: BQ25150, TPS61175

Can I use TPS61080 to create +/-20 V at 150mA supplies?

I see there is a tps6108x_design excel file that helps with components calculation. Would adding two Schottky diodes and caps C2, C4 be good enough ? Thanks.

over 4 years ago

0 Yichen Xu over 4 years ago

TI__Expert 4760 points

Hi John,

It depends on your input voltage. Note that the current limit of TPS61080 is only 0.5A.

Best Regards,

Yichen Xu

0 John Smith over 4 years ago in reply to Yichen Xu

Prodigy 120 points

My input voltage is between 3 and 5V. Yes to total TPS61080 is 0.5A, so I'm aiming to use only 0.3A. Thanks.

0 Yichen Xu over 4 years ago in reply to John Smith

TI__Expert 4760 points

Hi John,

The 0.5A is current limit of internal MOSFET, not output current. Since your input voltage is only 3~5V, the average input current is always higher than 0.6A with 20V, 150mA load. TPS61080 can not handle this. What are your desired working conditions? I may recommend other suitable device for you.

Best Regards

0 John Smith over 4 years ago in reply to Yichen Xu

Prodigy 120 points

Hi Yichen,

We need 100mA on each rail, so 100mA on 20V and 100mA on -20V. The input is from TI battery BQ25150's PMID, which is 1.5A @ 3~5V. If the output from the boost is too noisy, I think we could also have LDO stages for each rail, or a second stage LC filter. We need these power rails clean enough for TI OPAx991. Thanks Yichen.

+1 Yichen Xu over 4 years ago in reply to John Smith

TI__Expert 4760 points

Hi John,

TPS61175 could cover your power requirements. You need another diode on the output side and then create +/-20V output like the 61080 figure you attached.

Best Regards

Power management

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TPS61080: create +/-20 V at 150mA