Hello friends, power on process of *LA-6591P* is little bit different, because of *battery module power slecter section*, we will also discuss that section very soon,
Today we discuss some of basic power process of Rtc, 3.3valw and 5valw
Like we see Requirements of charging ic Pu11(isl88731c) are ...Inputs pin no 22 Dcin, Pin2 Acin( above +2.4 volt)
Outputs pin no 3 vref3,
Pin no 13 Acok/ Acav_in , (+3volt)
After that we see Requirement of pu2 (sn608098) to enable ldo and 3.3valw ,5valw are .....A) power_src, (vin of sn608098)
B) alwon which is generated by mec5055,
Question is how to generate *alwon by mec5055* .?
Now we will see power source of mec5055, only rtc supply is there, before 3.3valw, so now concentrate how to generate rtc supply,There are two source of rtc supply,
1) CMOS battery,
2) +3.3v_rtc_ldo which is generated by sn608098 pin no 5, that is a reference voltage output of sn608098 if vin is present reference voltage output required only 1uf/6.3v cap across to ground,
Both supply goes to PD1 if CMOS battery not available the Rtc power generate by sn608098,
So if we remove CMOS battery there are no problems it will power on because rtc voltage also available by sn608098, pd1 ouput line (main rtc source line) must be ok because mec5055 Dell power interface also pulled up by rtc power, Yes mec5055 is programmed, A little introduction of rtc power of la-6591p,
I hope you like,
