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Laptop cooling method

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Member level 5
Aug 27, 2010
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How laptop cooling fan automatic run when it getting heat.any idea about cooling fan function schematic circuit diagram.
Thank you

There is a temperature sensor on the motherboard which senses CPU heat and there is a fan controller on motherboard which adjusts PWM duty cycle that goes to fan to change the fan speed depending on temperature.

Thank you Mr. CMOS.
can tell me what is ic part no in temperature sensor?. how it's functioning?

Temperature sensor's output varies according to the temperature of the processor. It's output voltage increases with increase in temperature. Sensor output acts as feedback for controlling PWM for processor fan.

Hi Mr.yadavvlsi,
thank you for your post.
normally what is the average CPU (processor) temperature you have any one temperature sensor ic part no and give me some explain.
thank you

Processor's temperature sensor is installed above the processor. You are a laptop mechanic so you can see it.

Thank you for your post.i'm asking for any other temperature control circuit on the mother board? schematic diagram.........
thank you

Laptop when used continuously gets overheated, and to circulate the heat with the atmosphere there is a fan attached with every laptop. If a laptop is placed at a flat surface then it becomes quite difficult for the fan to force the heat out, so it is recommended that laptop should be kept at a place where from it is easy for fan to circulate the air. I saw that with my laptop that when it gets overheated and fan is not able to expel the heat out then it restarts itself or it gets shutdown automatically, overheating can also be harmful for the chips as well.

i actually have a laptop case that has the tiny pop-out kickstands that allows air to circulate and prevents the laptop from overheating

Apart from cpu control, if you see back of the fan, you see a thermister which senses air temp. Circuit in fan controls speed of the fan. If you shorten this thermister, fan runs at full speed

Sir, Same problem i m facing. Mr. kalimuthu have told me that i have problem of nvidia graphics chip. When it gets over heated my lappie automatically turns to hibernation mode. Sometimes my lappie works continuously for 10-12 hrs and works properly, but sometimes it turns to hibernation withing 15 mins. Can nvidia chip on MB is replaceable or i have to change my MB?
I have Hp pavilion dv2819tx. Plz tell me the solution.

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