Hello,I am use ms35fs6500 to provide power for mpc5744 ,the ms35fs6500 provide 1.25v,3.3v and 5v for mpc5744p,but the AD of mpc5744p have a big noise,and i have do this :
PMC.PMCCR.B.PMCCR_EN=0b1;
PMC.PMCCR.B.INT_REG_BYPASS=0b1;
the noise is still remain, I test all method ,and I find if i parallel a external 3.3v in my minimum system board ,then the noise is disappear.
The information is about this:
I use 2 PNP for ms35fs6500, the ms35fs6500 is in debug mode , the exposed pad of ms35fs6500 is not connect to GND, and the power dissipation of the minimum system board is small , the 1.25v,3.3v and 5v is normal.
why the noise is generate? what should i do?