Inverting DCDC

Takahiro Nishizawa

Genius 5575 points

Other Parts Discussed in Thread: TPS54240

I have a question.

Please tell us the best product that meets the following conditions.

Vin=12V

Vout=-6V

Iout=1A

The pin is out of the IC.

(No : SON, WSON, X2SON, QFN and so on)

(OK : SOT, HSOIC, TSSOP and so on)

Best regards,

Takahiro Nishizawa

over 7 years ago

0 JohnTucker over 7 years ago

TI__Guru**** 191445 points

Nishazawa-san,
I would probably start here: www.ti.com/.../description
There are technical resources here: www.ti.com/.../slva317, www.ti.com/.../slva540
And design tool here: www.ti.com/.../swiftinv-calc

0 Takahiro Nishizawa over 7 years ago in reply to JohnTucker

Genius 5575 points

Thank you for your answer!

I want to check Loop response.
But we cannnot check it by webench in negative output voltage .
Do you show us the data of Loop response?

Vin=12V
Vout=-6V
Iout=1A

Best regards,

Takahiro Nishizawa

0 JohnTucker over 7 years ago in reply to Takahiro Nishizawa

TI__Guru**** 191445 points

Nishazawa-san,
There is no way to simulate the loop characteristics for TPS54240 in the inverting buck boost configuration using the existing tools. You would have to estimate it by the non-inverting case, e.g. Vin = 18 V and Vout = 6 V. There are some TI devices that do support inverting buck boost in software. See LM2505 as an example:
www.ti.com/.../LM25005

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Inverting DCDC