On Thursday, November 22, 2012 6:36:32 PM UTC+8, wrote:
I have an old IRIS 4d/35 system with touchscreen capabilities and display is CRT type.



Recently we upgraded the system to run on LCD displays where we needed to provide the touchscreen controller with a separate power supply since the power for the controller was previously drawn from the CRT power supply.



However when a new switching power supply was used the touchscreen did not work. Reverting back to the supply from the CRT works flawlessly.



The supplies required for the touchscreen controller are 12V, -12V and 5V. The CRT power supply had a common ground and so does the new switching power supply.



Any idea what could be the problem with the new power supply. Any advise would be very much appreciated.


When we upgraded from CRT to LCD the touchscreen was upgraded at the same time. I suspect the problem is with the power supply as reverting back to the original solves the problem.