TPS61178: Design Questions

Qiang Ren

Part Number: TPS61178

Tool/software:

Hello Team,

Currently my customer is using TPS61178 in system and meet one design question, could you please help on it? Thanks!

The TPS61178 is connected to a 1V/5.5V power rail(The voltage may change between 1V or 5.5V in different board bring ups), which is powered before the TPS61178 output is enabled. The 1V/5.5V rail is connected by a diode and 1kOhm resistor to the TPS61178 output 12V, and the 1V/5.5V will power down when the TPS61178 output is enable.

We want to check with you if any risk of this design. Thanks!

Regards,
Qiang

5 months ago

0 Fergus He 5 months ago

TI__Genius 14345 points

Hi Qiang,

Thank you for reaching out.

Is the 1V/5.5V rail is connect to the output side of TPS61178 through a diode and 1k resistor?

If so, it should be ok.

External FET should be used to keep a true disconnect when TPS61178 is shutdown.

Best Regards,

Fergus

0 Qiang Ren 5 months ago in reply to Fergus He

TI__Intellectual 1595 points

Fergus,

Thanks for your reply. And I also want to check with you about the input impedance of the device, which I didn't find in the D/S. Thanks!

Regards,

Qiang

0 Fergus He 5 months ago in reply to Qiang Ren

TI__Genius 14345 points

Hi Qiang,

The input impedance should be related to the input capacitor, inductor and the loop gain.

Are all of your schematic parameters fixed already?

Best Regards,

Fergus

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TPS61178: Design Questions