topic Re: secure element se051 revers current in Smart Cards and Secure Element

secure element se051 revers current

Devkun — Tue, 02 Sep 2025 04:23:42 GMT

I'm using

I want to use the secure element feature to meet the Matter security criteria and the 14443A feature to implement Tap to Pair.

VIN Pin : in 3.3V DC Global net

Vout Pin pad to VCC Pin pad Connection.

SE051 switches on/off between VIN and Vout via the ENA pin.

When the switch is turned off, 14443a is activated..

Can the magnetically induced power from the NFC reader to the 14443 antenna affect the VIN?

Is the internal power switch of the SE051 protected against reverse current?

If this is not taken into consideration, can you suggest a solution?

Can I implement Matter's Tap to pair using SE051's 14443 feature?

Re: secure element se051 revers current

Kan_Li — Tue, 02 Sep 2025 06:10:02 GMT

Hi @Devkun ,

Can the magnetically induced power from the NFC reader to the 14443 antenna affect the VIN?

-No, it just supplies power to the same domain powered by VCC pin.

Have a great day,
Kan

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Re: secure element se051 revers current

Devkun — Tue, 02 Sep 2025 10:40:07 GMT

Thanks for the quick feedback.
i have a one more question.
According to the datasheet of SE051
The chosen interface is the only interface the SE051 will receive commands for processing. To select a different interface the IC needs to be reset.

My question is : can a reset be performed by controlling the ENA pin, thereby changing the interface?