laptop motherboard power remain on

[LS]

Hi,
In a HP NX9010 when I plug in the power the LCD lamp is ignited without I
push the power button.
After when I power on, the laptop work fine.
When I press the power button to shutdown, the lcd lamp remain ignite and a
sound-stop led remain on.
Wher is the problem ?
I think the cause of the problem is one of the this chip:
MAX3243C
LM339M
MAX1632EAI
Someone can help me ?
thanks

 

[Franc Zabkar]

Hi,
In a HP NX9010 when I plug in the power the LCD lamp is ignited without I
push the power button.
After when I power on, the laptop work fine.
When I press the power button to shutdown, the lcd lamp remain ignite and a
sound-stop led remain on.
Wher is the problem ?
I think the cause of the problem is one of the this chip:

MAX3243C

That's an RS232 interface chip.

LM339M

Quad comparator.

MAX1632EAI

Power Supply Controller for Notebook Computers

I'd be looking at this chip or the MOSFET switches on each of its
outputs.

See the application circuit on page 25 of this datasheet:
http://pdfserv.maxim-ic.com/en/ds/MAX1630-MAX1635.pdf

Someone can help me ?
thanks

- Franc Zabkar

 

[LS]

I'm testing this chip, but the pin 23 SHDN it's in automatic startup because
I read the same value of a v+ power input.
Can you explain me the automatic startup configuration ?
thanks

 

[Franc Zabkar]

I'm testing this chip, but the pin 23 SHDN it's in automatic startup because
I read the same value of a v+ power input.
Can you explain me the automatic startup configuration ?
thanks

Check pins 7 and 28. These control the 5V and 3.3V rails. Did you test
the MOSFETs for shorts?

- Franc Zabkar