A1708 820-00840 5V on USB-C after replaced charging chips. No liquid signs.

it-solve

Member
Hi Guys,

Have this board which had one USB-c with 5V looping U3100 and other with no voltage U3200. Replaced U3200 and got 5V voltage on both USB-C ports.
Replaced U3200 thinking that it may be faulty too, but still stuck at 5V


PPDCIN_G3_CHGR - 5V
PPBUS_G3 - 3.4V
PP3V3_G3H - 3.3V
F7000 - 2.3V
PP5V_S5 - 0V
P5V_S4 - 2.8V

TBA_VDDA - 5V
TBA_VDDP - 5V
TBA_BOOT1 - 1.8V
TBA_BOOT2 - 1.8V

L7670 - 2.8V

Where I should be looking? Any suggestions?


Something I have never come across before. One of the CD3215C chips I have replaced has different ID under the printed part. Have anyone seems anything like this?
Cannot make up the ID, but seems like TPS series used for usb-c controllers on laptops.

IT-Solve_20-07-29_08-48-22.jpg
 
Last edited:

2informaticos

Administrator
Staff member
"PPBUS_G3 - 3.4V"
Do you mean 3.4V at PPBUS_G3H?

Also I'm not sure if you really changed U3200 two times...

Post LDO voltages and diode mode on both CD3215 chips.
 

it-solve

Member
Probably I wasn't clear, I have not changed U3200 twice. I replaced both U3100 and U3200 I meant.

PPBUS_G3 - 3.4V - I am sure I read it 3.3V bit earlier, Now it shows 2.2V - 0.5 Diode mode

PP3V3_UPC_XA_LDO - 3.3V - 0.51 in diode mode
PP3V3_UPC_XB_LDO - 3.3V - 0.51 in diode mode

What are other LDO voltages?
 

2informaticos

Administrator
Staff member
"I replaced both U3100 and U3200 I meant."
I supposed that, but you only mentioned U3200 replacement two times (re-read first post); I wanted to be sure.
Post accurate information for the future.

"What are other LDO voltages?"
There are 4 LDOs; 1V1, 2x 1V8, 3V3.
 

it-solve

Member
Got it, sorry for the typo there.

LDO voltages are;
PP1V8_UPC_XA/B_LDOD - 1.8V - 0.5
PP1V8_UPC_XA/B_LDOA - 1.8V - 0.5
PP1V1_UPC_XA/B_LDO_BMC - 0V - 0.5
PP3V3_UPC_XA/B_LDO - 3.3V - 0.5

Thanks Again
 

2informaticos

Administrator
Staff member
Missing 1V1 LDO points to bad CD3215.
You should check voltage there when the charger is connected to corresponding port.
Really strange to have exactly 0.500 diode mode reading on all LDOs, never saw that.

Be aware of fake/remarked "new" CD 3215 chips...
 

it-solve

Member
Sorry I was rounding to decimals there, my bad.

You should check voltage there when the charger is connected to corresponding port.
Yes checked the both 1.1 and 1.8 voltages by swapping between 2 ports.

Usually, 5V is when usb-c chips are not communicating right? I will swap that "remarked" chip
 

it-solve

Member
Replaced the chip with one from the same batch. Same suspicious quality. Still no change from 5.13V on both ports

There is something new though. Seems like I have lost 1.8 LDOA and PP3V3 on the newly replaced chip U3200

PP3V3_G3H_UPC_XA/B - 3.41V - 0.364 - Reboots every 3-5sec

PP1V8_UPC_XA_LDOD - 1.796V - 0.476 - Stable
PP1V8_UPC_XB_LDOD - 1.801V - 0.472 - Reboots every 3-5sec
PP1V8_UPC_XA_LDOA - 1.824V - 0.508
PP1V8_UPC_XB_LDOA - 0.016V - 0.502

PP1V1_UPC_XA/B_LDO_BMC - 0V - 0.502

PP3V3_UPC_XA_LDO - 3.380V - 0.509 - Reboots every 3-5sec
PP3V3_UPC_XB_LDO - 0.016V - 0.540


I reflowed U3200 thinking it may not have settled well, but still same readings. Perhaps this whole batch is bad, what are the odds of that.

Unfortunately, this is my last 5 in this batch I ordered from Professional BGA chip factory. Which reminds me that I need to order more, these CD3215 are never enough.
Any suggestions on a good supplier?
 

2informaticos

Administrator
Staff member
You should test buying 2 chips from different stores.
Do NOT buy high quantity before assure the quality...

BTW, go for the port which doesn't restart first.
The restart possibly means that port is good and board tries to start; other issue (apart of USB-C) makes the board restarts.
 

it-solve

Member
Thanks for all of your help 2informaticos. I am giving up on this one.
I have replaced that chip and now I am getting completely different readings with high heat signature on the replaced U3100, while still stuck at 5V.
Additionally, I also detect a short on PP1V1_UPC_XA_LDO_BMC. Checked C3104 and is reading fine.

Either this whole batch of CD3215 is busted or there is something else there which is giving me inconsistent values.
 

2informaticos

Administrator
Staff member
Be aware of marking codes.
Original chips have a nice engraved marking, very easy to read.
Fake/remarked chips have serigrafied marking, almost impossible to read; many times needs to wet the chip with alcohol, to make code visible.
 
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