RTC PCF85363ATL and PCF85263ATL Internal protection

[satishghariya]

In RTC PCF85363ATL/AX and PCF85263ATL, Internal battery switchover circuit is present. Also both the parts are UL listed part.

My question here is--> Do we need to add series resistor or diode or both for the battery protection. Is there any internal current limiting protection on battery pin and also is any protection diode internally.

Regards,
Satish

[maw]

Hi TomasVaverka

Same here, is there any further documentation regarding this topic? The UL number might not suffice as argument for safety compliance.

BR

Markus

[TomasVaverka]

Hi Martin, Markus,

Please refer to the UM10301, Chapter 13.

https://www.nxp.com/docs/en/user-guide/UM10301.pdf 

Best regards,

Tomas

[maw]

Thanks, Tomas

In chapter 13 you mentioned, the following passage worries me:

All RTCs in this manual incorporate neither a dedicated switch-over circuit nor a charger and therefore this has to be realized with some external components. Only a few components are necessary to realize this as is illustrated in some example circuit

diagrams.

Doed this apply to the PCF85363ATL as well?

BR

Markus

[TomasVaverka]

Hi Satish,

There is only a diode protection, a series resistor needs to be added externally.

Best regards,

Tomas

[martin_studach]

Hi

Is there an official documentation / application note on this topic? In case I have to discuss it with a test laboratory or notified body?

Regards

Martin

[satishghariya]

Thanks Thomas,

Regards,

Satish