Why this mobo has MOSFET drivers but still use 3 MOSFET per phase? Thanks!
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Re: MOSFET and MOSFET driver problem
Two have same type, while other one is different. That tells me this is totem pole pull/push with coil connected at midpoint of the totem pole. This way this switching regulator can switch very fast instead of waiting for inductor to fall down on it's own due to energy stored in the coil from high to near low. Now, one transistor pulls voltage in on-off while other set off-on transition to yank the voltage down from high to low rapid enough.
This is necessary when you go above 40-50KHz and this is running around 100-250KHz range.
Cheers, Wizard -
Re: MOSFET and MOSFET driver problem
From what i have seen, the lower Mosfets are in paralel, to reduce resistance and rreduce heat and looses.
OEM`s may cheap down here and populate only one. This increases heat and drops efficency significantly.
As long as the MOSFET can handle the current, there is no need for an paralel MOSFET to run the circuit.
The input MOSFET is not switched on very long and currents are mutch lower (well at 12v input voltage to the inductor).
So it does not generate much loss in general.Last edited by gonzo0815; 08-28-2009, 11:51 AM.Comment
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Hello everybody,
I'm learning alone at home (with you) of course.
I have an Acer VX5-591G laptop that was given to me as scrap where I was training and diagnosing.
The Laptop turns on and starts to boot for a few seconds but before displaying any image it short circuits the main 19V power supply and turns off.
I managed to "repair" the laptop and it turns on and everything works, I even did game tests for the CPU and GPU and everything works but what I did was remove a Mosfet (PQ807) from the VCC_GT power supply.
The VCC_GT power... -
I tried to use this method:
Testing an N-channel MOSFET:
Step 1: Discharge the Gate (turn off the MOSFET)
Place the black probe (COM) on the Source (S) and the red probe on the Drain (D). The multimeter should show no continuity (high resistance or "OL" – open line).
Then, touch the black probe to the Source (S) and the red probe to the Gate (G). This discharges any stored charge in the Gate, turning the MOSFET off.
Step 2: Charge the Gate (turn on the MOSFET)
Now, place the red probe on the Gate (G) and the black probe on the...09-27-2024, 03:31 AM -
Hi! Please help to find mosfet driver name. Laptop is Asus UX535L. CPU PWM - NCP81215D, Mosfets on CPU - fdpc5030sg. Driver - DYU or DYP, cannot find it on google.... -
Hello everyone,
I am trying to repair a faulty power suplly for a LED Light.
I measure 0 V on the output so LED dont light up, however in the input (out of rectifier), I have 60 V, so the problem must be in the middle.
Capacitors seems to be good condition, diode is also good (I tested). No burn signals elsewhere.
I attached the pcb board and a shcematic that I draw from observing the PCB. Note that there is an IC with the letters "BVYDLA" (I think its that)... its the only thing I found written on IC.
I cant find datasheets of this PCB.... -
hi
i need a help
ive got a lenovo thinkpad E15 gen 2
the problem is, qb6 7466 n chanel mosfet get very hot (without battery temp.76 with a battery 150)
laptop start and work ok but after the mosfet get very hot its turns off...
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