Analysis process:
Measured voltage: 1.20V
Measured voltage: 1.27V
According to the DDR specification, the U11 supply voltage is no less than 1.283V
According to the I.MX6 specification, the U4 supply voltage below 1.35V will cause the processor to reduce the frequency.
Need help analysis:
According to the measured voltage 1.27V (U4 standard value is 1.4V), 1.2V (U11 standard value is 1.35V), U4 reference voltage VF=0.7324V, U11 reference voltage VF=0.7062 are calculated.
It does not correspond to the 0.8V 1% described in the specification,
Suspect that CPU 1.4V, DDR1.35V location voltage is too low is the reason why CPU restart and power failure can not start.
Two position voltage is too low will have CPU restart, unable to start, run the risk of exception. What are the reasons for this?