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
laptop motherboard power remain on
Apr 25, 2006
3 Replies
On Tue, 25 Apr 2006 21:48:15 +0200, "LS" put finger to keyboard and composed:
That's an RS232 interface chip.
Quad comparator.
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:
formatting link
- Franc Zabkar
Please remove one 'i' from my address when replying by email.
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" ha scritto nel messaggio news: snipped-for-privacy@4ax.com...
On Fri, 28 Apr 2006 13:45:10 +0200, "LS" put finger to keyboard and composed:
Check pins 7 and 28. These control the 5V and 3.3V rails. Did you test the MOSFETs for shorts?
- Franc Zabkar
Please remove one 'i' from my address when replying by email.
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