4 Replies Latest reply on Jul 8, 2019 5:14 AM by shahabamo

    Potential Issue on PS_SRST# Signal (MicroZed)

    shahabamo

      Hi,

       

      While Checking out MicroZed schematics (Rev.E), I noticed that the PS_SRST# signal is pulled up to 1.8V on Page 5. This signal is also connected to RST# pin of the SPI flash (U7), which is pulled up internally to 3.3V voltage (according to it's datasheet. The pull-up resistance is not declared). It seems that when the PS_SRST# signal is not driven low, It's something between 1.8 ~ 3.3, which may fall below The VIH threshold of SPI flash (0.7*VCC  = 2.31V) and prevent the SPI flash (or other 3.3V Reset inputs) to recover from Reset State.

      Please let me know that am I correct and Is it a safe design practice?

       

      -regards