eMachines E19T5W Service Manual - Page 19

19" LCD Color Monitor Emachine E19T5W +5V C701 NC/0.1uF U701SOT-223 NC/LT1117-18 3 VI 2 VO VO 4 C703 + NC/100uF/16V +3V3 C704 NC/0.1uF H1 8 7 6 99 18 27 36 5 5 4 4 TP H2 8 7 6 99 18 27 36 5 5 4 4 TP H3 8 7 6 99 18 27 36 5 5 4 4 TP 1 GND 1 2 3 1 2 3 1 2 3 BL_ADJ(DC) R31 C51 R32 R29 R33 Q4 0V ~ 3.3V 4.7K 1UF 0 X X X 0V ~ 5V 4.7K 1UF X 1K 4.7K MMBT3904 BL_ADJ R31 C32 P W M 47 N.C D C 4K7 1uF FTD7 FTD8 FTD9 FD Mark FD Mark FD Mark +5V C706 NC 3,4 +5V +12V C707 NC +5V GND 1 GND 3 +12V 5 GND 7 +5V 9 GND 11 CN701 2 BL_ON 4 BL_ADJ 6 +12V 8 GND 10 +5V 12 GND +5V R708 +5V R728 1K 1/10W 10K 1/10W C708 NC R705 2 R701 1K 1/10W 0 1/10W R706 0 1/10W 3 1Q7R07107 NC NC +5V Adj_BACKLIGHT 4 C709 0.1uF + C710 100uF/25V CONN C711 NC Q703 PMBS3904 R710 NC Q707 R712 PMBS3904 4.7K 1/10W + C719 47uF/16V +3V3 +5V +3V3 R716 NC R714 R717 10K 1/10W 10K 1/10W R715 NC R723 51K 1/10W VLCD VLCD 5 +5V +3V3 Q704 AO3401 R721 0 1/10W R722 NC 4 on_Panel R725 4.7K 1/10W C718 0.1uF C715 Q706 0.1uF/NC PMBS3904 C705 1uF/16V + C717 10uF/16V R727 10K 1/10W R711 30K 1/10W +5V 3,4 +5V R729 on_BACKLIGHT 4 D704 SR24 10K 1/10W 3,4 +5VA D704(SSM12L) Vf=0.38V and If=1A. So when system power on, the system loading is about 400mA (3.3V is about 200mA and 1.8V is about 200mA), So D35 changed from 1N4148(or BAT42) to SSM12L(schottky diode). P.S: The 1N4148 Vf=0.7V~1V can't meet LDO spec. The BAT42, Vf is OK but the If=200mA(forward current) can not meet current spec. 07/21 Q706 3904->3906 for pluse add c705 for inrush current D702 LL4148 D701 LL4148 Q702 PZT2907A R704 100 1/10W R702 VCTRL 4 51 1/10W + C702 4.7uF/16V VCC1.8 VCC1.8 4 R703 2K 1/10W VCC3.3 VCC3.3 4 D703(BAT54) Vf=0.53V (worst cauae) when If=100mA. So when system power off, the system loading is about 32mA, it is safe. +5VA +5VA C713 0.1uF 1 GND TO-263 U702 AIC1084-33PM 3 VI 2 VO VCC3.3 C712 + 100uF/16V C714 0.1uF VCC3.3 4 Title POWER Size Document Number B G2188-1-X-X-2-061215 Date: Friday , December 15, 2006 Sheet 3 of Rev 1 6 19