Question, i.MX28 power supply

[SLICE]

I would like to ask about i.MX28 power supply.

Could you show me what registers of i.MX286 are back-upped by battery.

Especially, my customer wants to know what registers among those are related to returning from backup state.

It is grateful if you can show that.  

Could you show me what behavior will occur on i.MX28 when supplying 3.3V when register setting of Battery(A15) pin is 4.2V?

Is it possible for i.MX28 not to boot-up?

Thanks,

Miyamoto

[Yuri]

Hello,

  The i.MX28 have so called persistent bits, shown in Table 12-11 (Persistent Bits)

and described in Chapter 22 (Real-Time Clock Alarm Watchdog Persistent Bits)

of i.MX28 Reference Manual, Rev. 2, 08/2013.

  As for Battery Input Voltage: it should be in range 3.1 V - 4.242 V.

But “with external loadings (for example, one DDR2 device and SD Card/NAND

 Flash), MX28 PMU was tested at BATT/DCDC_BATT > 3.30 V.

AN4199 (Using the i.MX28 Power Management Unit and Battery Charger

Getting Started with Power Supply) provides recommended i.MX28 power

configurations.

https://www.nxp.com/docs/en/application-note/AN4199.pdf 

Have a great day,
Yuri

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