TPS53319: Regarding Recommended operating condition for EN voltage

Daisuke Higa

Part Number: TPS53319

Hi support team.

I have a question regarding Regarding recommended operating condition for EN voltage.

I have referred to the following post.

https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/1016282/tps53319-enable-voltage-should-not-higher-then-vreg-for-0-8-v?tisearch=e2e-sitesearch&keymatch=TPS53319#

The absolute maximum rating of EN is 7V. (Recommended operation is 6.5V.)

If EN is not allowed above VREG + 0.8V, what happens when the EV voltage reaches 6.5V?

Since the maximum VREG voltage is 5.36V, it will exceed VREG + 0.8V.

Isn't the recommended operating condition for EN voltage up to 6.16V?

There is insufficient explanation as to why VREG + 0.8V should not be exceeded.

Best regards,

Higa

over 3 years ago

0 David_Daniels over 3 years ago

TI__Mastermind 24195 points

There is an ESD clamping circuit on EN pin.

https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/908546/tps53319-about-en-pin

VREG voltage can vary. If VDD is 4.5V, VREG can not be 5.36V, so the recommendation VREG + 0.8V. If the concern is the voltage level, use a 1kohm resistor in series like the EVM schematic. The concern is latching up the device, if the EN is greater than VREG by 0.8V

0 David_Daniels over 3 years ago

TI__Mastermind 24195 points

There is an ESD clamping circuit on EN pin.

https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/908546/tps53319-about-en-pin

0 Daisuke Higa over 3 years ago in reply to David_Daniels

Genius 4380 points

Hi Daniels-san

Thank you for answering.

I apologize my late response.

VREG_max is 5.36V at VDD=12V.

In this case, if EN=6.5V, my understanding is correct that I need to put a resistor in series?

Regards,

Higa

+1 David_Daniels over 3 years ago in reply to Daisuke Higa

TI__Mastermind 24195 points

The VREG at 5.36V is a corner case though possible, it is unlikely. The VREG can be between 4.77V to 5.36V but typically is 5.0V

If directly driving the EN pin with a voltage greater than 5.5V, I would use a 1kOhm in series.

A voltage greater than 1.6V is needed on EN pin, to enable the device. If using the resistor divider to VIN/VDD to EN to ground then the 1kohm is not needed .

0 Daisuke Higa over 3 years ago in reply to David_Daniels

Genius 4380 points

Hi Daniels-san

I apologize my late response.

Thank you for your support.

I understood.

Thanks.

Regards,

Higa

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TPS53319: Regarding Recommended operating condition for EN voltage