TPS65185: Schematic review

Vincent LINTILHAC

Part Number: TPS65185

Hi,

I have some issues with my PMIC, none of the rail are coming up when I pulled up WAKEUP and POWERUP, and I cannot access the device through I2C.

I ordered some extra chips to try to switch it, in case I overheated it, but I would like to make sure that my problems are not coming from design issues.

Can you help me reviewing my schematic (I pull up the POWERUP pin externally and Vin voltage is 3.2V).

Also, is to ok to left POWERUP floating if I use the I2C register to turn the PMIC in ACTIVE mode, or should it be pulled-up or connect to WAKEUP?

Best,

Vincent L.

over 5 years ago

0 Gerard Copeland over 5 years ago

TI__Genius 10610 points

Hi Vincent,

I am not able to see your schematic. Can you please try attaching it again?

Thanks,

Gerard

0 Vincent LINTILHAC over 5 years ago in reply to Gerard Copeland

Prodigy 70 points

Sorry the picture didn't went through.

Vincent

0 Gerard Copeland over 5 years ago in reply to Vincent LINTILHAC

TI__Genius 10610 points

Hi Vincent,

I believe the following schematic concerns are the reason the PMIC will not power up:

The VN net must be supplied by the inverting buck-boost converter output. This is the node connecting D3 and C17.
The VB and VIN nets should be switched. VIN corresponds to C19. VB corresponds to C18.

Additional comments on the schematic:

TI recommends capacitor voltage ratings at least two times the expected DC bias.
A 4.7 uF decoupling capacitor is recommended at the VDDH_IN input.

Thanks,

Gerard

0 Gerard Copeland over 5 years ago in reply to Gerard Copeland

TI__Genius 10610 points

Hi Vincent,

Additionally, if PWRUP is unused it is recommended to pull the pin up to a defined voltage level, such as VIO. In this case I2C can still be used to transition between STANDBY and ACTIVE states.

Thanks,

Gerard

0 Vincent LINTILHAC over 5 years ago in reply to Gerard Copeland

Prodigy 70 points

Thanks for your time and answers.

Best,

Vincent

Power management

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TPS65185: Schematic review