https://community.nxp.com/t5/Other-NXP-Products/PCAL6416AHF-misbehaves-when-machine-starts/m-p/1368933#M12511 <P>Please find attached the video of misbehavior of I2C GPIO expander in field. It works fine when the machine is stopped!</P><P>The connections are as below:</P><P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="gpio expander" style="width: 639px;"><img src="https://community.nxp.com/t5/image/serverpage/image-id/161757iB74CA3B7C9C444E2/image-size/large?v=v2&amp;px=999" role="button" title="expander.png" alt="gpio expander" /><span class="lia-inline-image-caption" onclick="event.preventDefault();">gpio expander</span></span><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="LEDs" style="width: 284px;"><img src="https://community.nxp.com/t5/image/serverpage/image-id/161758i4730FA0245434CD2/image-size/large?v=v2&amp;px=999" role="button" title="leds.png" alt="LEDs" /><span class="lia-inline-image-caption" onclick="event.preventDefault();">LEDs</span></span></P><P>The GPIO expander works fine when the machine starts,<BR />The LEDs stop working!</P><P>The values of the control registers and data registers are printed on display for debug purpose, as seen in video top right and left corners.</P><P>(motor[17Hp] &lt;- Supply -&gt; SMPS -&gt; Controller [buck converter] -&gt; LCD module [buck converter])</P> Wed, 10 Nov 2021 05:23:43 GMT Ashok_Sharma 2021-11-10T05:23:43Z https://community.nxp.com/t5/Other-NXP-Products/PCAL6416AHF-misbehaves-when-machine-starts/m-p/1368933#M12511 <P>Please find attached the video of misbehavior of I2C GPIO expander in field. It works fine when the machine is stopped!</P><P>The connections are as below:</P><P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="gpio expander" style="width: 639px;"><img src="https://community.nxp.com/t5/image/serverpage/image-id/161757iB74CA3B7C9C444E2/image-size/large?v=v2&amp;px=999" role="button" title="expander.png" alt="gpio expander" /><span class="lia-inline-image-caption" onclick="event.preventDefault();">gpio expander</span></span><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="LEDs" style="width: 284px;"><img src="https://community.nxp.com/t5/image/serverpage/image-id/161758i4730FA0245434CD2/image-size/large?v=v2&amp;px=999" role="button" title="leds.png" alt="LEDs" /><span class="lia-inline-image-caption" onclick="event.preventDefault();">LEDs</span></span></P><P>The GPIO expander works fine when the machine starts,<BR />The LEDs stop working!</P><P>The values of the control registers and data registers are printed on display for debug purpose, as seen in video top right and left corners.</P><P>(motor[17Hp] &lt;- Supply -&gt; SMPS -&gt; Controller [buck converter] -&gt; LCD module [buck converter])</P> Wed, 10 Nov 2021 05:23:43 GMT https://community.nxp.com/t5/Other-NXP-Products/PCAL6416AHF-misbehaves-when-machine-starts/m-p/1368933#M12511 Ashok_Sharma 2021-11-10T05:23:43Z