not charging... no 3.3v... power manager?

Question

iPad Air Wi-Fi

首先你得要准备一部iPad Air（1rd Gen）只支持Wi-Fi的机型这里我们指的是A1474机型它拥有64位的A7双核处理器并拥有16,32,64GB甚至是128GB的内存选择

20 个问题查看全部 | 35配件购买

Dolcebimbo72 @dolcebimbo72

声誉积分: 43

3

1

发帖于: 2016年12月8日

更多选项

not charging... no 3.3v... power manager?

Hi guys... I', struggling trying to solve an issue with this iPad Air...this is the scenario: while off, when connectin lighting cable it switches on but it does not charge the battery... what\s weird is that there is no "not chargin" message near battery icon... simply nothing.

Analyzin with multimeter there are no shorts at all in the board, but 3.3 volts rail is completely missing..... all the other voltages are present. I tested continuity between dock pins soldered to the board and checkpoint and everything is ok... I already replaced the charging IC (U6000) but no result.... each and every smd belonging to PP3V3_ACC line is good and functional... should I replace the power manager (U8100) or anyone of you can suggest me other solutions? thanks everyone in advance....

已回答！ 显示答案我也有这个问题

这是一个好问题吗？

是否

得分 0

添加一条评论

1个答案

已选择的解决方案

Minho @refectio

声誉积分: 221.8千

15

295

808

发帖于: 2016年12月8日

更多选项

The PP3V3_ACC line is only present when the phone powers on. Otherwise, unless there is an accessory plugged into the Lightning port, you don't need to worry about it.

Did you check all the rails generated by the PMIC, there are a few dozen?

Perhaps your Tristar replacement did not succeed and you should try it again.

EDIT

This is the Tristar circuit. Check the following voltage rails

PP3V0_S2R_TRISTAR

PP1V8_S2R_TRISTAR

PPVBUS_PROT

(but not PP3V3_ACC)

You should be able to find the schematic on the web

这个答案有帮助吗？

是否

得分 1

3条评论:

and could you tell me what are exactly the rails to check, the ones involved in battery charging process?

由 Dolcebimbo72 完成的 2016年12月8日

the voltage rails you mentioned are present... I thought the problem was in PP3V3_ACC just because battery is not charging.... so confused :-(

由 Dolcebimbo72 完成的 2016年12月8日

As I said, perhaps your Tristar replacement did not succeed. You should also check all the PMIC rails, the problem could be elsewhere. Good luck!

由 Minho 完成的 2016年12月8日

添加一条评论

and could you tell me what are exactly the rails to check, the ones involved in battery charging process? — Dolcebimbo72
the voltage rails you mentioned are present... I thought the problem was in PP3V3_ACC just because battery is not charging.... so confused :-( — Dolcebimbo72
As I said, perhaps your Tristar replacement did not succeed. You should also check all the PMIC rails, the problem could be elsewhere. Good luck! — Minho

iPad Air Wi-Fi

not charging... no 3.3v... power manager?

1个答案

添加你的答案