820-2850-A: battery not detected

[mon2]

Re: 820-2850-A: battery not detected

Replace Q7035. It is defective. From where do you purchase electronic parts? If you are in Europe, do you have a VAT #? If yes, may be able to drop ship from Arrow.com.

Digikey / Mouser / RS Electronics may have this or valid replacement part.

Then there is AliExpress as well.

It is not a bad idea to source some of the other mosfets and perhaps a fresh U7000 for your toolbox.

[DrFalken]

Re: 820-2850-A: battery not detected

Replace Q7035. It is defective. From where do you purchase electronic parts? If you are in Europe, do you have a VAT #? If yes, may be able to drop ship from Arrow.com.

Digikey / Mouser / RS Electronics may have this or valid replacement part.

Then there is AliExpress as well.

It is not a bad idea to source some of the other mosfets and perhaps a fresh U7000 for your toolbox.

I'm in Italy, I have VAT # and sometimes I buy from Mouser and TME.
Do You think I should change also Q7030 ?
I've some AON6312 (30V 83A) & AON6414A (30V 30A) and some other up to 24A: can I use them just to check if there's anything else bad before I place the order ?
Can I put back L7030 ?
Thank you !!!

[mon2]

Re: 820-2850-A: battery not detected

I will suggest to solder back L7030 after we can confirm that U7000 with the new mosfet is working properly.

Once ppbus_g3h is restored, then solder back L7030.

Will check on the mosfets inventory and specs once at the office and update this thread.

[DrFalken]

Re: 820-2850-A: battery not detected

I will suggest to solder back L7030 after we can confirm that U7000 with the new mosfet is working properly.

Once ppbus_g3h is restored, then solder back L7030.

Will check on the mosfets inventory and specs once at the office and update this thread.

Great, thank you !

[mon2]

Re: 820-2850-A: battery not detected

Q7035 from Renesas is available from Aliexpress.

However, both Q7030 & Q7035 mosfets should be fine to be replaced with the:

Texas Instruments p/n CSD17506Q5A

https://www.arrow.com/en/products/cs...?q=CSD17506Q5A

The common pin pitch (1.27mm) and metal belly for the drain pins should allow for the same soldering footprint. That is, pins 5-6-7-8 are bonded together underside the TI and Renesas parts so they will fit the same footprints on the PCB.

Send me a PM and share your address & VAT # - should be able to drop ship it to you from Arrow (Europe).

[DrFalken]

Re: 820-2850-A: battery not detected

Q7035 from Renesas is available from Aliexpress.

However, both Q7030 & Q7035 mosfets should be fine to be replaced with the:

Texas Instruments p/n CSD17506Q5A

https://www.arrow.com/en/products/cs...?q=CSD17506Q5A

The common pin pitch (1.27mm) and metal belly for the drain pins should allow for the same soldering footprint. That is, pins 5-6-7-8 are bonded together underside the TI and Renesas parts so they will fit the same footprints on the PCB.

Send me a PM and share your address & VAT # - should be able to drop ship it to you from Arrow (Europe).

Thank you for the hints!
I've an account with Arrow and will see to order the TI mosfets from them: I'll update the thread when replaced

[DrFalken]

Re: 820-2850-A: battery not detected

Q7035 and Q7030 just replaced with CSD17506Q5A
New Q7035 readings:
resistance between SOURCE (1-2-3) & DRAIN (5-6-7-8) of Q7035 > 2MegaOhm
resistance between SOURCE (1-2-3) & GATE (4) of Q7035 > 2MegaOhm
resistance between GATE (4) & DRAIN (5-6-7-8) of Q7035 > 2MegaOhm

Also:
L7030 pad #1 > 2 MegaOhm

[mon2]

Re: 820-2850-A: battery not detected

Ok. Good readings on the replacements.

Remove all power and check the details of the battery mosfet @ Q7055.

Meter in resistance mode (2k scale).

Measure & post the readings for:

source (1-2-3) & drain (5-6-7-8)
source (1-2-3) & gate (4)
gate (4) & drain (5-6-7-8)

Searching again for a low resistance.

Also, while in resistance mode, check the resistance of D6950 (dual ESD diode) pins 1 & 2. Both should be of a HIGH resistance otherwise, D6950 is defective.

If the readings are NOT of a low resistance then power up again with the battery.

Post the voltage readings of Q7055 battery mosfet for:

source (1-2-3)
gate (4)
drain (5-6-7-8)

While you are in voltage mode, check the voltages present on pins 1 & 2 of the dual ESD diode @ D6950 (pin # 1 & 2). Ideal case is that these are with ~3v3-~3v42 each since these open-drain lines are each pulled upto 3v42.

Any chance your battery is still charged ? If not, this test will have to do.

[DrFalken]

Re: 820-2850-A: battery not detected

Ok. Good readings on the replacements.

Remove all power and check the details of the battery mosfet @ Q7055.

Meter in resistance mode (2k scale).

Measure & post the readings for:

source (1-2-3) & drain (5-6-7-8)
source (1-2-3) & gate (4)
gate (4) & drain (5-6-7-8)

Searching again for a low resistance.

Readings on Q7055
source (1-2-3) & drain (5-6-7-8) > 2MegaOhm
source (1-2-3) & gate (4) > 2MegaOhm
gate (4) & drain (5-6-7-8) 2MegaOhm

Also, while in resistance mode, check the resistance of D6950 (dual ESD diode) pins 1 & 2. Both should be of a HIGH resistance otherwise, D6950 is defective.

4 KiloOhm

If the readings are NOT of a low resistance then power up again with the battery.

Post the voltage readings of Q7055 battery mosfet for:

source (1-2-3)
gate (4)
drain (5-6-7-8)

While you are in voltage mode, check the voltages present on pins 1 & 2 of the dual ESD diode @ D6950 (pin # 1 & 2). Ideal case is that these are with ~3v3-~3v42 each since these open-drain lines are each pulled upto 3v42.

Any chance your battery is still charged ? If not, this test will have to do.

Voltage readings of Q7055 with the battery:
source (1-2-3) = 9.74V
gate (4) = 0
drain (5-6-7-8) = 9.74V

D6950 pin 1 = 0
D6950 pin 2 = 0

But probably the battery is almost empty...

Note: both F7040 and L7030 are still removed from the board

[mon2]

Re: 820-2850-A: battery not detected

Solder back L7030. Check the resistance to ground of both sides of L7030. Should remain as a high resistance.

Then solder back the fuse F7040. Check the resistance again on F7040. Should be a high resistance.

Then power up and confirm the voltage @ F7040.

The resistance on D6950 is good.

Voltage on D6950 is not good but it is linked to PPBUS_G3H which we have dismantled.

Check again once the parts are back on the logic board (F7040 & L7030).

[DrFalken]

Re: 820-2850-A: battery not detected

Solder back L7030. Check the resistance to ground of both sides of L7030. Should remain as a high resistance.

Then solder back the fuse F7040. Check the resistance again on F7040. Should be a high resistance.

Then power up and confirm the voltage @ F7040.

The resistance on D6950 is good.

Voltage on D6950 is not good but it is linked to PPBUS_G3H which we have dismantled.

Check again once the parts are back on the logic board (F7040 & L7030).

Before I solder back L7030 & F7040 I've checked voltages on their pads:

L7030 pad #1 (CHGR_PHASE): 0
L7030 pad #2 (PPVBAT_G3H_CHGR_REG): 9.74V
F7040 pad #1 (PPVBAT_G3H_CHGR_REG): 9.74V
F7040 pad #2 (PPBUS_G3H): 0

When I'll solder F7040, pad #2 (PPBUS_G3H) will have the same voltage of pad #1 (PPVBAT_G3H_CHGR_REG)=9.74V: is this correct ?

L7030 soldered:
GND to L7030 pin #1 > 2MegaOhm
GND to L7030 pin #2 > 2MegaOhm

L7030 & F7040 soldered:
GND to F7040 pin #1 > 2MegaOhm
GND to F7040 pin #2 > 2MegaOhm

[DrFalken]

Re: 820-2850-A: battery not detected

Put battery back.

Voltage readings:
F7040 pin #1 = 2.85V
F7040 pin #2 = 2.85V
D6950 pin #1 = 0.33V
D6950 pin #2 = 0.33V

[DrFalken]

Re: 820-2850-A: battery not detected

Removed battery and removed L7630, other readings:

- L7630 pad #1 to GND = 32 KiloOhm
- L7630 pad #2 to GND = 12 Ohm

- Q7630 pin 5 to GND > 2MegaOhm
- Q7630 pin 1-2-3 to GND = 31 KiloOhm
- Q7630 pin 4 to GND = 137 KiloOhm
- Q7630 source (1-2-3) & drain (5-6-7-8) > 2MegaOhm
- Q7630 source (1-2-3) & gate (4) = 106 KiloOhm
- Q7630 gate (4) & drain (5-6-7-8) > 2MegaOhm

- Q7635 pin 5 to GND > 2MegaOhm
- Q7635 pin 1-2-3 to GND = 0 (GND)
- Q7635 pin 4 to GND > 2MegaOhm
- Q7635 source (1-2-3) & drain (5-6-7-8) = 31 KiloOhm
- Q7635 source (1-2-3) & gate (4) > 2MegaOhm
- Q7635 gate (4) & drain (5-6-7-8) > 2MegaOhm

[mon2]

Re: 820-2850-A: battery not detected

1) Solder back L7630. The resistance is ok for this low voltage rail.

2) Remove the battery.

3) Apply the power adapter, what is the voltage reading for F7040, pin #1 ?

Since F7040 is soldered in place, the same voltage should be present on pin # 2 - confirm it.

This is a check for PPBUS_G3H and should be ~12V.

4) If you do not see this voltage on PPBUS_G3H, then power down and remove F7040 fuse again.

Then power up without this fuse and check the voltage @ F7040, pin # 1.

5) If you do see the proper voltage for PPBUS_G3H, check the voltage again for D6950.

D6950 pin #1 = 0.33V
D6950 pin #2 = 0.33V

these are not good voltage readings...

Post your readings.

6) The battery mosfet is still a suspect @ Q7055.

Remove all power. Meter in resistance mode (2k scale).

Measure the resistance for:

source (1-2-3) & drain (5-6-7-8)
source (1-2-3) & gate (4)
gate (4) & drain (5-6-7-8)

For these checks, you will use red meter probe on one pin group & black meter probe on the other pin group. Repeat for each 3 of the tests.

The voltage that you are presently reading is from the partially charged battery ending up on PPBUS_G3H.

[DrFalken]

Re: 820-2850-A: battery not detected

1) Solder back L7630. The resistance is ok for this low voltage rail.

2) Remove the battery.

3) Apply the power adapter, what is the voltage reading for F7040, pin #1 ?

Since F7040 is soldered in place, the same voltage should be present on pin # 2 - confirm it.

F7040 pin #1 = 0.48V
F7040 pin #2 = 0.48V

I'm gonna remove F7040 and report

[DrFalken]

Re: 820-2850-A: battery not detected

4) If you do not see this voltage on PPBUS_G3H, then power down and remove F7040 fuse again.

Then power up without this fuse and check the voltage @ F7040, pin # 1.

F7040 pad #1 = 0.08V
F7040 pad #2 = 0.48V

5) If you do see the proper voltage for PPBUS_G3H, check the voltage again for D6950.


these are not good voltage readings...

Post your readings.

D6950 pin #1 = 3.35V
D6950 pin #2 = 3.35V

6) The battery mosfet is still a suspect @ Q7055.

Remove all power. Meter in resistance mode (2k scale).

Measure the resistance for:

source (1-2-3) & drain (5-6-7-8) > 2 MegaOhm
source (1-2-3) & gate (4) > 2 MegaOhm
gate (4) & drain (5-6-7-8) > 2 MegaOhm

For these checks, you will use red meter probe on one pin group & black meter probe on the other pin group. Repeat for each 3 of the tests.

The voltage that you are presently reading is from the partially charged battery ending up on PPBUS_G3H.

Q7055 readings:
source (1-2-3) & drain (5-6-7-8) > 2 MegaOhm
source (1-2-3) & gate (4) > 2 MegaOhm
gate (4) & drain (5-6-7-8) > 2 MegaOhm

[mon2]

Re: 820-2850-A: battery not detected

Q7055 resistance is fine.

Remove the battery, leave off F7040 fuse.

With the adapter connected, carefully measure & post the voltages on each pin of the U7000 IC.

U7000 may be defective but will know more after these measurements.

Also, PPBUS_G3H normal voltage may be lower for this logic board but it certainly should not be as low as you are reading. So far, this is showing that the battery voltage is passing through onto the PPBUS_G3H common rail ok but U7000 side is not creating a similar voltage when the adapter is connected.

reference reading on PPBUS_G3H:

https://www.logi.wiki/index.php?title=PPBus_G3H

[DrFalken]

Re: 820-2850-A: battery not detected

Q7055 resistance is fine.

Remove the battery, leave off F7040 fuse.

With the adapter connected, carefully measure & post the voltages on each pin of the U7000 IC.

U7000 may be defective but will know more after these measurements.

Also, PPBUS_G3H normal voltage may be lower for this logic board but it certainly should not be as low as you are reading. So far, this is showing that the battery voltage is passing through onto the PPBUS_G3H common rail ok but U7000 side is not creating a similar voltage when the adapter is connected.

reference reading on PPBUS_G3H:

https://www.logi.wiki/index.php?title=PPBus_G3H

Ok, I'll report very soon.
BTW I did the previous voltages measurements without battery, only with AC Adapter: should I repeat with both battery and AC adapter together ?

[DrFalken]

Re: 820-2850-A: battery not detected

U7000 only with AC adapter:

Pin01 (CHGR_AGATE) = 7.3V
Pin02 (PPCHGR_DCIN) = 16.36V
Pin03 (CHGR_ACIN) = 3.86V
Pin04 (CHGR_VFRQ) = not measured
Pin05 (CHGR_ICOMP) = 0V
Pin06 (CHGR_CELL) = 3.41V
Pin07 (CHGR_VCOMP) = 0V
Pin08 (CHGR_VNEG) = 0V
Pin09 (CHGR_AMON) = 0V
Pin10 (SMBUS_SMC_5_G3_SDA) = 3.34V
Pin11 (SMBUS_SMC_5_G3_SCL) = 3.34V
Pin12 (PP3V42_G3H) = 3.42V
Pin13 (CHGR_RST_L) = 3.42V
Pin14 (SMC_BC_ACOK) = 2.32V
Pin15 (CHGR_BMON) = not measured
Pin16 (CHGR_BGATE) = 0V
Pin17 (CHGR_CSO_N) = 0.8-0.7-0.6 decreasing
Pin18 (CHGR_CSO_P ) = 0.8-0.7-0.6 decreasing
Pin19 (PP5V1_CHGR_VDD) = 0V
Pin20 (PP5V1_CHGR_VDDP) = 0V
Pin21 (CHGR_LGATE) = 0V
Pin22 (GND) = 0V
Pin23 (CHGR_PHASE) = 0.6-0.5-0.4 decreasing
Pin24 (CHGR_UGATE) = 0V
Pin25 (CHGR_BOOT) = 0V
Pin26 (CHGR_SGATE ) = not measured
Pin27 (CHGR_CSI_N) = 2.0-1.9-1.8 decreasing
Pin28 (CHGR_CSI_P ) = 1.2-1.19-1.18 decreasing

[mon2]

Re: 820-2850-A: battery not detected

Pin19 (PP5V1_CHGR_VDD) = 0V
Pin20 (PP5V1_CHGR_VDDP) = 0V

Replace U7000. These pins should not be 0V and pretty sure these pins are from an internal LDO that feeds from pin 2 as the input voltage.

If U7000 has been replaced or was faced with possible liquid damage, consider to flux and reflow the part to test again. Fairly inexpensive part from Aliexpress or other sources.