No Power DAZAARMB6E0 REV E

[kalilinux25]

Hi Ive check the dcin at the PR188 it has 3.5-3.7v not stable.

Checking
PQ17 is ok not shorted
PIN5- 19V
PIN 3,21 -3.5-3.7 not stable
PIN4 -3.5-3.8V not stable

ACN- 3.6-3.9V
ACP- 3.6-3.9V
CMSRC -3.6-3.9V
ACDRV- 3.6-3.9V
ACOK -0V
ACDET - 2.7V
IADP -0V
IDCHRG- 0V
PMON-0V
PROCHOT-0V
ILIM-0V
LDODRV-0V
PHASE-0V
HIDRV-19V
BTST-5.6V
REGN- 5.9V

LINK to schematic https://www.badcaps.net/forum/troubl...60#post1581660

[mcplslg123]

Re: No Power DAZAARMB6E0 REV E

Replace PC122 & PC123 with exact same value. Rating of cap is very important here. i know that both the caps will measure good but still replace them.

[Adenitz]

Re: No Power DAZAARMB6E0 REV E

ACDRV shoud be about 25V. This voltage goes to gate and opens PQ17, so 19 V can pass through.
Please remove all power (DC IN an battery too) and then measure resistance to ground on pins 1, 2 and 3. This battery charger IC chip has built in MOSFET Short-Circuit Protection, so check PQ20, PQ1 and PQ2.
By checking MOSFET I assume check resistance D-S, D-G and G-S. Also check resistance to ground on each legs (D,S and G).
It is possible that short circuit is detected somewhere and BQ24780S turned OFF input MOSFET.

[kalilinux25]

Re: No Power DAZAARMB6E0 REV E

Replace PC122 & PC123 with exact same value. Rating of cap is very important here. i know that both the caps will measure good but still replace them.

im havig a problem looking a exact value I fount a 1n/50v and 0.1u50v is it same?

[kalilinux25]

Re: No Power DAZAARMB6E0 REV E

ACDRV shoud be about 25V. This voltage goes to gate and opens PQ17, so 19 V can pass through.
Please remove all power (DC IN an battery too) and then measure resistance to ground on pins 1, 2 and 3. This battery charger IC chip has built in MOSFET Short-Circuit Protection, so check PQ20, PQ1 and PQ2.
By checking MOSFET I assume check resistance D-S, D-G and G-S. Also check resistance to ground on each legs (D,S and G).
It is possible that short circuit is detected somewhere and BQ24780S turned OFF input MOSFET.

Ive check the PQ20 and PQ1 and PQ2 with diode and ohms mode to be sure but all readings are ok sir..the BQ24780S is also new but same issue .. I also make sure that all pins is soldered properly undermicroscope..

[mcplslg123]

Re: No Power DAZAARMB6E0 REV E

since there is no shorts, try a jumper from pin5 of PQ17 to PR8(CMSRC side). Be careful not to connect at VA2 side. Plug your dc again and hopefully you will get 24V at pin4 of PQ17. Report back.

[kalilinux25]

Re: No Power DAZAARMB6E0 REV E

since there is no shorts, try a jumper from pin5 of PQ17 to PR8(CMSRC side). Be careful not to connect at VA2 side. Plug your dc again and hopefully you will get 24V at pin4 of PQ17. Report back.

I only get same voltage reading 3.5-3.8 notstable

[Adenitz]

Re: No Power DAZAARMB6E0 REV E

So, you jumped PQ17 (connect pin 5 of PQ17 where you have 19V to PR8) and still have only 3.5V??

If you checked MOSFETS PQ1, PQ2 and PQ20, there is no danger to jump the MOSFET PQ17.
I don't think it is a good idea to jump PQ17 to CMSRC, because 4 k ohm resistor is there to limit the current and protect IC charger chip.
After checking PQ1 PQ2 and PQ20, I would jump PQ17 to VA2.

[kalilinux25]

Re: No Power DAZAARMB6E0 REV E

So, you jumped PQ17 (connect pin 5 of PQ17 where you have 19V to PR8) and still have only 3.5V??

If you checked MOSFETS PQ1, PQ2 and PQ20, there is no danger to jump the MOSFET PQ17.
I don't think it is a good idea to jump PQ17 to CMSRC, because 4 k ohm resistor is there to limit the current and protect IC charger chip.
After checking PQ1 PQ2 and PQ20, I would jump PQ17 to VA2.

VA2 I only have 3.3v on the NBSWON# but missing 3vpcu and 5vpcu

[kalilinux25]

Re: No Power DAZAARMB6E0 REV E

since there is no shorts, try a jumper from pin5 of PQ17 to PR8(CMSRC side). Be careful not to connect at VA2 side. Plug your dc again and hopefully you will get 24V at pin4 of PQ17. Report back.

VA2 I only have 3.3v on the NBSWON# but missing 3vpcu and 5vpcu

[mcplslg123]

Re: No Power DAZAARMB6E0 REV E

3VPCU/5VPCU will not generate as +19V is not crossing the 1st dc-in mosfet. Problem is definitely related to BQ24780S and/or dc-in fets.

[kalilinux25]

Re: No Power DAZAARMB6E0 REV E

3VPCU/5VPCU will not generate as +19V is not crossing the 1st dc-in mosfet. Problem is definitely related to BQ24780S and/or dc-in fets.

i tried 3 BQ24780S
ic but same readings sir what should i look for?

[mcplslg123]

Re: No Power DAZAARMB6E0 REV E

Replace the caps as suggested earlier.

[kalilinux25]

Re: No Power DAZAARMB6E0 REV E

Replace the caps as suggested earlier.

I already changed it same issue I get the caps from ACER ZQ0 parts

[kalilinux25]

Re: No Power DAZAARMB6E0 REV E

I tried to remove the
PR188
and put voltage at the dc in and test the PR188 PIN 1 git 19v stable and 5.6v at the pin 2

[kalilinux25]

Re: No Power DAZAARMB6E0 REV E

Hoping someone can guide me

[mcplslg123]

Re: No Power DAZAARMB6E0 REV E

If you inject +19V directly on CLR, do you get +3V & +5V ALW ?? BQ24780 wont work if anything is wrong in +3V rail.

[reformatt]

Re: No Power DAZAARMB6E0 REV E

ACOK is 0V. It should be 3V (voltage divider PR30/PR195 for REGN6V), unless it's being pulled low. Therefore, refer to the datasheet as to the conditions for ACOK to be pulled low:

The open drain ACOK output can be pulled to external rail under the following conditions:
• VVcc_UVLOZ < VVcc < ACOVP
• Vacdet > 2.4 V
• VVcc –Vsrn> VVcc_srn_fall + VVcc_srn_hyst

Provided Vcc is between the min and max limits, ACDET is above 2.4V, then your problem will lie in the last condition. Check components on the SRN pin and again, PC122 and PC123 are absolutely critical for the hysteresis part of the equation in terms of type and value.

[kalilinux25]

Re: No Power DAZAARMB6E0 REV E

If you inject +19V directly on CLR, do you get +3V & +5V ALW ?? BQ24780 wont work if anything is wrong in +3V rail.

Ididnt get any voltage on 3v and 5v

[mcplslg123]

Re: No Power DAZAARMB6E0 REV E

Ididnt get any voltage on 3v and 5v

Then check requirement of 3V/5V regulator.