LM5116: Can we use LM5116 for 12V to -55V/1.4A application

Jimmy WANG

Genius 4065 points

Part Number: LM5116

Hi team,

Can we use LM5116 for 12V to -55V/1.4A application. Could you help review the schematic? thanks!

Vin=12V

Vo=-55V@1.4A

over 4 years ago

0 Timothy Hegarty over 4 years ago

TI__Guru 73402 points

Hi Jimmy,

This topic is already discussed on this thread: https://e2e.ti.com/support/power-management/f/power-management-forum/995448/design-a-ibb-that-meeting--55v-1-4a-output-when-input-12v

My recommendation is to add more ceramic input capacitance from VIN to -VOUT across the FETs as this provides the switched current to the power stage. Also, consider increasing the soft-start cap given the high Cout value. Finally, check compensation based on the output cap effective ESR.

Regards,

Tim

0 Jimmy WANG over 4 years ago in reply to Timothy Hegarty

Genius 4065 points

Hi Timothy,

I use TINA to simulate LM5116, but can not work.

Could you help me check the schematic correctness? thanks!

LM5166-12V to -55V.TSC

0 Timothy Hegarty over 4 years ago in reply to Jimmy WANG

TI__Guru 73402 points

HI Jimmy,

This may be related to the GND connection in the model for IBB. Another option here is PSPICE for TI.

Regards,

Tim

0 Jimmy WANG over 4 years ago in reply to Timothy Hegarty

Genius 4065 points

Hi Timothy,

So TINA can not do this simulation(GND connection)? Could you please help confirm the schematic?

The design condition 12V to -55V can normally work?

0 Timothy Hegarty over 4 years ago in reply to Jimmy WANG

TI__Guru 73402 points

Hi Jimmy,

See Figure 8 of app note snva856: http://www.ti.com/lit/snva856

Regards,

Tim

0 Jimmy WANG over 4 years ago in reply to Timothy Hegarty

Genius 4065 points

Hi Tumothy,

I cannot open it. Could you share PDF here? thanks!

+1 Timothy Hegarty over 4 years ago in reply to Jimmy WANG

TI__Guru 73402 points

Try this link: https://www.ti.com/lit/an/snva856a/snva856a.pdf ...or search for snva856 on ti.com

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LM5116: Can we use LM5116 for 12V to -55V/1.4A application