Hi all,
I am facing a clock disturbance issue. I have 10 PCBs all connected in a cascaded style. Each PCB have 2 sptic6c595 used to drive seven segment displays. All the shift registers are driven by a single mcu. The displays on very last PCB gets disturbed after some time. The disturbance is due to clock line(SRCK) because if i touch the clock line (with something non conductive) on any PCB, the display starts to behave well. The clock line is quite long and shared among all shift registers. I also found that if the clock line is touched on all PCBs to the points where they are soldered, the last display starts working fine otherwise display gets corrupted (Segments half turned on). I am stuck at this point and i am pretty sure nothing else is disturbing these segments because the soldering, wires and mcu firmware has been double checked. Any help related to this clock issue would be appreciated. I have also attached the PCB schematic. The problematic line is black-arrowed. Blue line shows the track on PCB and Yellow line depicts that it is a jumper.
I am facing a clock disturbance issue. I have 10 PCBs all connected in a cascaded style. Each PCB have 2 sptic6c595 used to drive seven segment displays. All the shift registers are driven by a single mcu. The displays on very last PCB gets disturbed after some time. The disturbance is due to clock line(SRCK) because if i touch the clock line (with something non conductive) on any PCB, the display starts to behave well. The clock line is quite long and shared among all shift registers. I also found that if the clock line is touched on all PCBs to the points where they are soldered, the last display starts working fine otherwise display gets corrupted (Segments half turned on). I am stuck at this point and i am pretty sure nothing else is disturbing these segments because the soldering, wires and mcu firmware has been double checked. Any help related to this clock issue would be appreciated. I have also attached the PCB schematic. The problematic line is black-arrowed. Blue line shows the track on PCB and Yellow line depicts that it is a jumper.
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