LM5122ZA: negative input to high positive output

Denny Huang

Expert 7170 points

Part Number: LM5122ZA
Other Parts Discussed in Thread: PMP20371, LM5122, LM5156

Dear Team

May I know if TI have any suitable solution, either device or reference design, for the following spec?

Input voltage: -34V to -60V range

Output voltage: 12V

Output current: 0.6A

Many thanks

Denny

over 4 years ago

0 Youhao Xi over 4 years ago

TI__Guru* 78630 points

Hi Denny,

Thank you for reaching out. Yes this can be supported by a boost controller or converter in the inverting buck-boost configuration like shown in the following ref design:

https://www.ti.com/tool/PMP20371

Obviously the ref design has a much higher power than you need, and the components can be scaled down. You may submit a ref design request to the PDS group.

Thanks,
Youhao

0 Denny Huang over 4 years ago in reply to Youhao Xi

TI__Expert 7170 points

Hi Youhao

Sorry, The output voltage is 54V, dose pmp20371 is suitable for the spec?

Input voltage: -34V to -60V range

Output voltage: 54V

Output current: 0.6A

Many thanks

Denny

0 dehuan Qi over 4 years ago in reply to Denny Huang

TI__Intellectual 2775 points

Hi Denny,

If the output is 54V, the SW voltage is more than 114V, so LM5122 can't handle such high voltage.

This output power is not large, it is recommended to use the non-synchronous scheme. you can check LM5156.

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LM5122ZA: negative input to high positive output