Request for VBAT Interrupt Test Report of PCF85263A

[姚栋]

Dear NXP Team,  
Could you provide the official test report confirming the INT pin functionality  
in VBAT-only mode for PCF85263A (Rev.5.3)?
My application scenario is: after the MCU initializes the RTC, it cuts off its own power supply. When the set time is up, the main power circuit is awakened by the RTC's interrupt signal. It is required that 1) the RTC can issue an INT signal when only the backup battery is powered on. 2) the power switching event can be turned off to avoid interruption and interference with the normal operation of 1). thank you. yaodong160@126.com

Dear NXP Team, 

Could you provide the official test report confirming the INT pin functionality 

in VBAT-only mode for PCF85263A (Rev.5.3)?
My application scenario is: after the MCU initializes the RTC, it cuts off its own power supply. When the set time is up, the main power circuit is awakened by the RTC's interrupt signal. It is required that

1) the RTC can issue an INT signal when only the backup battery is powered on.

2) the power switching event can be turned off to avoid interruption and interference with the normal operation of 1).

thank you. yaodong160@126.com

[JozefKozon]

Dear Dong,

there isn't any test report regarding the PCF85263A VBAT power source to interrupt functionality. The functionality of the interrupts are described throughoutlly in the PCF85263A datasheet. 

1) the RTC can issue an INT signal when only the backup battery is powered on.

2) the power switching event can be turned off to avoid interruption and interference with the normal operation of 1).

[A] Do you mean, that the Interrupt function should be available only when the PCF85263A is powered by the battery? If yes, this is not possible. The Interrupt function is not based on what is the VBAT powered from. If you mean something else, please rephrase your question.

With Best Regards,

Jozef

[姚栋]

My question is: When VDD is powered off and VBAT is powered on, after pulling up the INT pin with VBAT, can the INT voltage be lowered when the timed alarm interrupt arrives? Can you confirm this? Can we also disable the interrupt output corresponding to VDD/VBAT switching by configuring it? Thank you for your prompt reply.

[JozefKozon]

Dear Dong,

thank you very much for clarification. 

My question is: When VDD is powered off and VBAT is powered on, after pulling up the INT pin with VBAT, can the INT voltage be lowered when the timed alarm interrupt arrives? Can you confirm this? Can we also disable the interrupt output corresponding to VDD/VBAT switching by configuring it? Thank you for your prompt reply.

[A] Yes, this is possible. Please refer to the section 7.9 in the PCF85263A datasheet. You can set, what will generate interrupt. It makes no difference if the PCF85263A is powered from VDD or VBAT. 

If you want to disable the interrupt when the PCF85263A is powered from VDD, then you can disable the interrupt in the registers.

To check if the PCF85263 is powered from VDD or VBAT can be by INTA pin. 

However if you will use the INTA for battery mode indication, then you cannot use it as the INTA output. You can use the INTB pin instead. 

With Best Regards,

Jozef