(2) SIL504 trouble shooting: (U4, U2)
X1, 20Mhz?
RESET successful?
YES
System IIC ok? (U4 pin 15,14)
YES
SIL504 IIC ok? (U4 pin 2, 3)
YES
DEINTDONE Signal ok? (U4 pin21)
No
No
No
No
1.check X1, C41, C42
2.check U17,RP25
1.Q2,Q3 ok? (level shift )
2. RP7 ok? ( IIC Pull high)
1.R10,R11ok? ( IIC Pull high)
2.Replace U4
1.check SIL504 1.8V ok?
2.check U2, U3 ok?
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