ISL question

[MDY]

ISL6259 recives 20V and vdd at 5V. But pin 14 ACOK is 0.50V.
PPBUS is 0.50V too and no short to ground.
17,18 and 27,28 measure ok.
Anything more to check before replace isl6259?

Board was liquide damage but comes to me completly cleaned. No green light.

 

[dukefawks]

ISL seems dead to me, but very limited info.

 

[MDY]

What more should I measure? Need more pins?

 

[MDY]

Well, I replaced ISL but still PPBUS at 0V and acok at 0.30V

 

[larossmann]

R7005 resistance is what? What is the resistance to ground on PPBUS_G3H? What voltage is on CHGR_ACIN pin of 6259?

 

[MDY]

Board is 820-4924

acin - 4.90V
R7105 - 20ohm
ppbus - .0L and .170 in diode mode.
ppbus - 1V
CHGR_DCIN - 20V

 

[dukefawks]

If pin 2 receives 16V+ and ACIN is 4.9V, ACOK should come high at least. Measurement on PPBUS is also worryingly low. What is resistance to GND on PPBUS?