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820-4924 q7130

G

grmacs

Member
Hi there, I have a q7130 that is causing a short via diode check on PPBUS_G3H. with part gone none of the points where chip was go to ground except the points that should. I ordered a part from mouser but it appears it isn't configured the same because when I solder new one on, it registers 0.5V on PPVBAT G3H diode to ground with new chip on the board. I've double checked its alignment and making sure there's not enough solder there to bridge to any of the ground points. Is there a part off any of the 2011/2 mbp logics or mac air logic that would work for q7130?
Chip that was there has 4902nf RDUOZ on it
New chip says 4902NF RGI5T

THis is what I ordered: NTMFD4902NFT1g from mouser.
If not it can I order this?:

10pcs NTMFD4902NFT1G 4902NF ORIGINAL MOSFET N-CH DUAL 30V 8DFN 4902 NEW | eBay

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2informaticos

2informaticos

Administrator
Staff member
"q7130 that is causing a short via diode check on PPBUS_G3H"
What was the exact value of that short, in diode mode (red probe at ground)?

"it registers 0.5V on PPVBAT G3H diode to ground with new chip on the board"
You should worry about PPBUS_G3H because of Q7130, not about PPVBAT_G3H.
However, check if Q7155 is not shorted.
 
G

grmacs

Member
ppbus_g3h is .142V with Q7130 on board and F7140 removed.

q7155 not shorted.

I have to assume I have the wrong chip for replacement of q7130, correct?

with q7130 chip off, only 3,4,5 pin pads are ground. DIode test black probe (red to ground) at any other pad point q7130 is .4 or higher. As soon as I put chip back on everything on that circuit drops diode test readings.
 
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G

grmacs

Member
0.142V drop diode check red probe to ground is good for PPBUS_G3Hw f7140 removed? Is that typical or board specific?
 
2informaticos

2informaticos

Administrator
Staff member
Use Google and read about Schottky and normal Si diodes.
Then check diode mode on PPBUS_G3H on boards w/ and w/o integrated Schottky diode...
 
G

grmacs

Member
Had weird readings at ISL, tried resoldering then replaced so I think ISL is good:
1-0
2-16.5V
3-4V
9-0
12-3.4V
13-3.4V
14-3.31V
17-0
19-5.5V
20-5.5V
27-16.5V
17/18- 3.5ohm
27/28-20.2ohm

PPBUS_g3H - 0V diod red to ground=.131V
 
2informaticos

2informaticos

Administrator
Staff member
Check all components around U7100 and resolder all there.
Pay atention to R/C networks from pins 5, 7, 8.
Do you have 3V at pin 6?
 
G

grmacs

Member
Man... scratching my head...
yes 3V at pin 6
Touched up all. checked things around 5, 7, 8. Replaced related caps there just in case 7142/15/16.

Getting some voltage at PPBUS_G3H pulsing 3.9-4.1V
 
2informaticos

2informaticos

Administrator
Staff member
Remove F7140 and check again voltage at L7130.
Checl all the traces between Q7130 and U7100, as to other components too.
 
G

grmacs

Member
THink I had some bad solder. FInally circled back to this board and did some resoldering aroun u7100 and q7130. Plugged in and got a snap sound from something toward fan end of board. Not seeing any visible evidence of what happened but I have 12.3V at PPBUS G3H now steady.

GUessing the snap was somehing SMC related? checked around there after researching the boards here a bit:

Have 3+ volts at SMC RESET L, SMC ONOFF, SMC VDDA, SMC PM G2 EN However I do not have anything at SMC Adabpter EN...

I reflowed the SMC but my best guess as a newb is smc needs to be replaced? or no?
 
2informaticos

2informaticos

Administrator
Staff member
Check signals and voltages for U5000 (2 OF 2) at page 38.
Be sure to get oscillation from Y5110.

Also check voltage and diode mode at SCL/SDA lines of battery bus.
R7100 is good?
 
G

grmacs

Member
R7100 is good
Others not previously posted u5000:
smc wake L - 0V
pp3v3_s5_AVREF_SMC is 3.3V
PP1V2_S5_VDDC is 1.2V

Y5110
Pin 1 .218V steady (no oscope)
Pin 3 is .237V Steady

SMBUS SMC 5G3 SCL= 0V and .003V red probe to ground diode
/SDA pulses .2V then 3.42V then 0V-ish quickly to .2V and back to 3.42V repeats and .5V to red probe to ground diode
 
2informaticos

2informaticos

Administrator
Staff member
You have a good reason for your symptom.
Find the short at SMBUS_SMC_5_G3_SCL line.
D7050 is first to chek, if soldered of course.
 
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G

grmacs

Member
SMC. No luck after pulling d7050, looking around traces, pulled ISL.... nada, pulled SMC and .503V drop on SCL now.
Replacing SMC (first attempt at SMC for me) fun fun fun.
 
G

grmacs

Member
Well damn it. SMC replacement went well I believe but now I'm back to an issue with PPBUS_G3H is steady 8.65V. Had low resistance at R7185 due to q7180. Now that resistance is looking right. 8.65V PPBUS seemed like it would be a CELL problem I guessed but I have 3.42V at pin 6 of U7100 and good solders there. CHanged U7100 just in case redouble triple checked solders on that and still 8.65V at PPBUS_G3H.

Damn damn damn... I thought for sure i'd be set after SMC but I'm guessing I have a voltage somewhere thats borderline? cleaned the hell out of the board wondering if maybe something somewhere was pulling down voltage just enough to screw my PPBUS voltage.
 
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