https://community.nxp.com/t5/Sensors/MPXH6400AC6T1/m-p/1388984#M6797 <P>Hello,</P><P>These pins must be leave unconnected since these pins are used for factory calibration, you must not connect to external circuitry or ground, otherwise you will probably change the calibrations values causing a malfunction of the device, or even worst, the device could be permanently damaged.</P><P>So, as I mentioned before, I do recommend leave these pins unconnected.</P><P>I hope this information will be useful for you. I am glad to help.</P><P>Best regards,</P><P>David</P> Fri, 17 Dec 2021 20:57:02 GMT diazmarin09 2021-12-17T20:57:02Z https://community.nxp.com/t5/Sensors/MPXH6400AC6T1/m-p/1388964#M6796 <P>There are 4 pins that state "Do not connect to external circuitry or ground." Is it recommended to connect these DNC pins together to provide better structural strength for the sensor? Will this affect any signals? Removing tubing can sometimes cause the sensor to be ripped from the PCB.</P> Tue, 03 Feb 2026 20:55:01 GMT https://community.nxp.com/t5/Sensors/MPXH6400AC6T1/m-p/1388964#M6796 cwtengr 2026-02-03T20:55:01Z https://community.nxp.com/t5/Sensors/MPXH6400AC6T1/m-p/1388984#M6797 <P>Hello,</P><P>These pins must be leave unconnected since these pins are used for factory calibration, you must not connect to external circuitry or ground, otherwise you will probably change the calibrations values causing a malfunction of the device, or even worst, the device could be permanently damaged.</P><P>So, as I mentioned before, I do recommend leave these pins unconnected.</P><P>I hope this information will be useful for you. I am glad to help.</P><P>Best regards,</P><P>David</P> Fri, 17 Dec 2021 20:57:02 GMT https://community.nxp.com/t5/Sensors/MPXH6400AC6T1/m-p/1388984#M6797 diazmarin09 2021-12-17T20:57:02Z