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imx535qsb ,mc34708 's output is  vsrtc=1.2 instead of 1.3v?

Question asked by yan jianping on Oct 18, 2012
Latest reply on Oct 20, 2012 by yan jianping

i I finished  a board full of references to imx53qsb reference schematic. I used the MC34708 PMIC as the demo does that.

in this design I  use  MC34708 to power the iMX535.The system should be  automaticaly startup when the power comes up,but i fail.

in the design ,pums[5:1]=00111;ictest=gnd;

and i have tested  these parameters:

vccbp=3.8v

VCOREDIG =1.496v;

vcore=2.775v;

vREFCORE =1.19v;

valways =3.785v;

vddlp=1.476v;

vsrtc=1.234v

PWNON1=1.496v;

PWNON2=0;

PMIC_ON_REQ=0v?

so ,i have some questions :

1)vsrtc is 1.2v instead of 1.3v?

2)vpll,sw2,sw1,and so on ,  approach to 0v?

3)but i tested qsb (tp12),i find PMIC_ON_REQ=1.3v and PMIC_STBY_REQ(tp5)=0.and i want to know the difference between the qsb(the qsb  system has no sd card to boot yet) and my design .and this difference hanppened beacuse vsrtc is different ?

 

Is there anybody who has experiance with auto startup the MC34708 ?


 

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