BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

[jamesp]

Hello Guys,
need help here...i bought a MB from aliexpress for my samsung np500p4c-so5aewith pcb BA41-01938A PTC, model xidan-14 rev. 1.2.
the board does not work and i checked with my multimeter p3.3v_aux and 5v_alw on, but no output reading. have checked the tps51125 for the entrip1 and entrip2 signal both have no enable signal, KBC3_SUSPWR and KBC3_USBCHG both no output to trigger q571 and q575 resulting entrip1 and entrip2 signal pulled down by q574 and q572.
i suspecting the bios chip not communicating with SIO MEC1310 Because when i checked with my DSO rigol1054z, there is no spi clk and thus no decoding read by my DSO.
my question is, is the BIOS FLASH the culprit or Some components out there?
help is highly appreciated thanks!

[mon2]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

Was the board purchased as non-working? You should contact the vendor and copy AliExpress staff as a complaint if the vendor does not assist for a proper resolution. You have a limit timeline for this complaint.

[jamesp]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

the board was bought a year ago by my friend, and he dont ask for any help until now only, he asked for me to checked this newly bought but non functional board. that is why i doubt if the hardware is the culprit because it looks new.
he cant complain now to aliexpress, maybe some guy out here can help me to help my friend (because he is not a techie guy)

[mon2]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

I think we have the same scope but have not used any of the logic analyzer functions. Have a dedicated tool for spi bus study. Love the scope so far.

If you are not getting the enables, they are often driven by the KBC IC. The KBC may need to be reflashed. Post the schematic if available or at least the KBC part number. Then wait on additional advice.

The main bios is usually driven by the PCH which features the SPI master.

Does the CPU or PCH get warm or hot?

Is the main power rail if ~19v present? This should be after the typical 2*DCin mosfets. The mosfets will be driven by the gate pins of each by the charger IC.

Which charger IC is onboard?

[jamesp]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

i screenshot the schematic pertaining the entrip1 and entrip2. attached here as png file. you are correct, the kbc which happens to be MEC1310 is the one that talking to spi rom w25q32bv, and voltage reading on myspi rom is...
pin1...2.156
pin2...0.213
pin5...1,0 -1.1
pin6...0.210
i know that voltage measurement does mean nothing, and i have used before my DS1054z to decode the MOSI and MISO out of this spi rom but i cant get a result even i flashed this from different bios dump from this site through other threads. and i noticed a no clocked input and CS signal coming from EC MEC1310. i checked the clocked generator but its ok, as i measures a 32khz output going to the EC.
i also attached here the schematic as my ref.

[jamesp]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

PS... 19v rail is complete. EC Chip and TPS51125 is not warming up. but the EC have 3v supply coming from TPS51125 LDO but theres no 3v and 5v coming out due to as i have said the KBC3_suspwr and KBC3_usbchg have no output from MEC1310 that will enable entrip1 and 2

[mon2]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

What is the voltage on pin #8 of this spi flash?

Is the KBC warm or hot to the touch?

[jamesp]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

3.3v on pin 8 and pin 7, ....pin 3 and 4 is tied on ground.
KBC is cold dead

[mon2]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

Good voltage.

Both, entrip1 and entrip2 are active high pins but unable to see how these pins will see a logic high to enable each.

The mosfets that drive these pins will only produce a logic low. Perhaps there are internal pull ups inside the tps device??

[jamesp]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

to enable both entrip1 and 2, is to have logic high on kbc3_SUSPWROR KBC3_USBCHR., but it is not happening.
PLS. SEE attachment for the desired logic.

[mon2]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

To me, G_ = ground but maybe drawn strange.

What are the voltage readings of pin #2 of the mosfets that connect with the entripx pins?

[jamesp]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

both for entrip1 and 2 are zero readings.
what do you think? is my EC firmware corrupted?

[mon2]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

Not sure since the first gate voltage is '1' (logic high).

Do you have a voltage on the pull up resistors with _STB labels?

There must be pull resistor or similar also on these entripx pins.

The mosfet will open = high impedance or close = pull the entripx to ground.

How will these pins receive a logic '1' status?

Will review it tomorrow. Time for beauty sleep.

[jamesp]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

if pin1 of both q571 and q575 is high, AFAIK the P5.0v (with stb label) on both pin 3 will be pulled down, thus switching off both q572 and q574. and if that happensentrip1 and entrip2 will be left connected by r1082 and c1136 for entrip2, and r1071 and r1070 for entrip1.
...and it is not happening now on the mainboard of my friend

[jamesp]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

NEED HELP, does anyone knows this mainboard??

[mon2]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

What is the voltage of pin #13 (EN0) of the TPS (reports??) IC?

[jamesp]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

it is TPS51125RG , and pin13 reads 4.6 vdc

[jamesp]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

r104, r1045 and r1046 are Not present on actual mainboards. and it indicates at 19v it should have at least 3.7v based on schematic. and upon checking it reads 4.6v.

[mon2]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

For the switching power rail outputs that are missing on the tps51125, remove all power and measure the resistance to ground at the output inductors.

Post the measurements.

[jamesp]

Re: BA41-0938A PTC BOARD Model XIDAN-14 Rev 1.2 need help

600kohms down to 50kohms then back again to 600k, maybe due to capacitor across L507 to gnd and L10 inductors to gnd. but definitely is not shorted.
temperature is dead cold. as there was no 3.3v_alw and 5.0v_alw output from L10 and L507, the only outputi get is the 2.0v ref , 3.3v LDO and 5.0v ldo on pin3,8 and 17 respectively of tps51125.
as per datasheet of tps51125, if entrip1 and entrip2 is enabled...it should produce an output on L507 and L10, andthats my problem i think. en0 is ok, VIN is also ok. the missing link is the entrip1 and entrip2 voltage. according to the the datasheet iread, if a 150k resistor is put acroos the entrip2 like in the given schematic, i should expect a 1.5v, but since the gate of the mosfet q574 was at high logic and the pin 6 goes directly to ground thereby negating the purpose of 150k pull down resistor, thats why im getting no voltage reading