HP DM1 Laptop Doesn’t Boot, +VCC_CORE Voltage Missing

A HP laptop doesn’t boot, press power button, the current 0.35A stopped, According to experience, doubt power supply for cpu problem. So test +VCC_CORE (PL13), found +VCC_CORE voltage missing. Observe carefully, there is a small hole on the lower mosfet PQ26, it was damaged. Removed PQ26, test the resistance between PL13 inductor and gnd, the value is normal.

So, replace a new PQ26, connect power and boot again, the current still is 0.35A and stopped. Touch power ic RT8165B, very hot, suspected it was damaged, so replace a new RT8165B. Boot again, the current 0.20A stopped, +VCC_CORE voltage missing, yet. Take the schematic diagram, test +VIN, VCC, PVCC, EN, etc,...read more 

ASUS X43B Laptop Doesn’t Trigger, EC Doesn’t Reset

A asus x43b notebook, doesn’t boot, connect power adapter, the current 0.005A, standby 3V, 5V voltages are normal. When press the power button, the laptop doesn’t trigger, the current doesn’t change. So check EC’s working conditions first, the EC chip is KB930QF A1.

So check power, clk, reset singal, found 37-Pin ECRST# singal voltage is 0.24V only, it isn’t normal. +3VALW is normal, and R1605 plus C1533 are RC Time delay circuit, to 37-Pin reset EC.  read more , By the way, In order to thank for every new and old customers and friends, offer 10% off from November 16th to November 30.

TPS51621 QFN-40 Power IC

http://www.htic-tool.com/tps51621-qfn40-power-ic-p-1657.html

TPS51611 QFN-32 Power IC

http://www.htic-tool.com/tps51611-qfn32-power-ic-p-1656.html

TPS51610 QFN-32 Power IC

http://www.htic-tool.com/tps51610-qfn32-power-ic-p-1655.html

TPS51511 QFN-20 Power IC

http://www.htic-tool.com/tps51511-qfn20-power-ic-p-1654.html

TPS51461 QFN-24 Power IC

http://www.htic-tool.com/tps51461-qfn24-power-ic-p-1653.html

TPS51427 QFN-32 Power Controller IC

http://www.htic-tool.com/tps51427-qfn32-power-controller-ic-p-1652.html

HP Compaq 511 Laptop Doesn’t Boot, Current 0.182A Fault

A HP Compaq 511 laptop, Press the power botton, the current 0.182A, then auto power off, doesn’t boot.

According to the current value, so doubt the power circuit problem, test +3VS, found the voltage is missing. +5VS voltage is normal.

So, check mosfet Q39 control G pole, the GATE_3S_R voltage is 0.24V only, it is not normal. Due to +5VS is normal, so GATE_3S is normal, just check GATE_3S_R circuit....read more

TPS51220A QFN-32 Power IC

http://www.htic-tool.com/tps51220a-qfn32-power-ic-p-1650.html

TPS51222 QFN-32 Power Controller IC

http://www.htic-tool.com/tps51222-qfn32-power-controller-ic-p-1651.html

HP 500 Laptop Clock Circuit Diagram And Failure Analysis

1, U28(ICS 954226) clock chip, if damaged, it will not respond when press the power button. Or auto reboot, or auto power off after led light. If 954226 pseudo soldering, will be able to boot sometimes, can not boot sometimes.  

2, L31, L32 inductor, if damaged or pseudo soldering, it will not respond when press the power button, or auto power off.

3, X1 crystal oscillator, if damaged, will not able to boot.

4, C428, C431 resonant capacitor, if electric leakage or damaged,...read more

TPS51218DSCR PIZI QFN-10 Power IC

http://www.htic-tool.com/tps51218dscr-pizi-qfn10-power-ic-p-1649.html

TPS51211 QFN-10 Power IC

http://www.htic-tool.com/tps51211-qfn10-power-ic-p-1648.html

UCC3804N DIP-8 PWM IC

http://www.htic-tool.com/ucc3804n-dip8-pwm-ic-p-1647.html

HP 500 Laptop Power Supply For Chipset Diagram And Failure Analysis

1, PU8(MAX8743) power control chip for chipset, if damaged, will not able to boot, or the fan rotations but cannot boot. Or auto power off after work for a period of time, or chipset very hot.

2, PQ20 mosfet, if damaged, will auto power off after work for a period of time, or cannot boot.

3, PL9 inductor or PC71 capacitor, if pseudo soldering, will auto power off after boot....read more

UC3854BDW SOP-16 ADVANCED HIGH-POWER FACTOR PREREGULATOR IC

http://www.htic-tool.com/uc3854bdw-sop16-advanced-highpower-factor-preregulator-ic-p-1646.html

UCC2818DW SOIC-16 Current-Mode SMPS Controller IC

http://www.htic-tool.com/ucc2818dw-soic16-currentmode-smps-controller-ic-p-1645.html

uP6215AK QFN-48 Power IC

http://www.htic-tool.com/up6215ak-qfn48-power-ic-p-1644.html

HP 500 Laptop Charging Control Circuit Diagram And Failure Analysis

1, PU1 (BQ24703) charging control chip, if damaged, the battery will not be able to chare. Or there is no response when press the power button. Or cannot boot.

2, PQ9 charging control mosfet, will not able to boot, plug power adapter, the led flicker.

3, PR19 resistor, if open circuit or pseudo soldering, will can not charge, or charge can not up to 100%.

4, PQ4 if damaged, only normal boot when power supply via battery, but system halted when power supply via the adapter.

5, PQ2 if damaged, only noot normal when power supply via the adapter,..read more

uP6209AQ QFN-24 Power IC

http://www.htic-tool.com/up6209aq-qfn24-power-ic-p-1643.html

UP6207BI QFN-32 Power IC

http://www.htic-tool.com/up6207bi-qfn32-power-ic-p-1642.html

UP6205A QFN-24 Power IC

http://www.htic-tool.com/up6205a-qfn24-power-ic-p-1641.html