RTC battery circuit of i.MX6 Dual-lite

[inhojeon]

Hi,all!

I have a question about RTC Battery circuit of i.MX6 Dual-lite.

below that is schematics of SABRE BD about RTC part.

I don't understand that circiut. (ex. Is U500 just charing battery for RTC? or another working something?)

Let me that circuits is how to working,ASAP.

Best Regards,

Inho Jeon.

[Yuri]

Hello,

    one of supply sources should be used for P3V15_BACKUP : external battery

or U500. The header for the battery is not mounted, so U500 is used by default.

In order to apply the battery : "Cut shunt [SH500] and wire to header to operate
with external battery" - as noted on the scheme.

Have a great day,

Yuri

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[inhojeon]

Hi, Yuri.

Thank you for your reply.

You mean U500 is just like dummy external battery,is it right?

And, To use real RTC external Battery, not use U500 olny connect battery, is that right?

I have questions.

Recommend me about Voltage level of RTC external battery

And, If use rechargeable RTC ext battery, to recharge RTC battery at turn on systems need another recharing battery circuits?

MMPF100NPAZES have a LICELL Charger on datasheet.

Best Regard,

Inho Jeon.

[Yuri]

  Please look at my comments below.

1.

Yes, U500 serves as dummy battery, to use real RTC external Battery -  do not use U500 ;

olny connect battery.

2.

Please refer to i.MX6 Datasheet(s) for RTC voltage.

Say, from IMX6DQCEC (Rev. 4, 07/2015)  : VDD_SNVS_IN min =2.8 V,   max= 3.3 V

3.

Yes, a recharger scheme is needed for rechargeable battery.

Regards,

Yuri.

[inhojeon]

Hi, Yuri.

Thank you for your relpy.

And, below that is MMPF0100NPAZES blockdiagram.

But, Connect Li-on battery is not charging.

Is that another need circuit?

Best Regards,

Inho Jeon.

[Yuri]

  Please refer to section 6.4.7.1.1 (Coin cell charger control) of
the Datasheet.

http://www.nxp.com/files/analog/doc/data_sheet/MMPF0100.pdf?fasp=1&WT_TYPE=Data%20Sheets&WT_VENDOR=F...

Regards,

Yuri.