I have the following circuit that consists of a Monostable Multi-vibrator, SN74LVC1G123 configured to detect a falling edge upon button press and outputs a logic HIGH which in turn is inverted using the Open Drain Inverter SN74LVC1G06. The problem is that the inverter is not inverting the output pulse from the SN74LVC1G123. The output of the Inverter is pulled up externally. What am I missing here?

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    \$\begingroup\$ So if it does not work, how does it work then? The '123 output goes high and low according to button press? The 1G06 output does not invert but buffers? Or is it always high or low? \$\endgroup\$
    – Justme
    Mar 18, 2022 at 15:43
  • \$\begingroup\$ Does Output Pullup work or is there a connection failure? try external pullup or down with 1k,, does voltage change ? Is input voltage correct? \$\endgroup\$ Mar 18, 2022 at 16:23
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    \$\begingroup\$ @Justme The 123 outputs does as expected. Goes high and low depending on the button state, however the inverter output is always high. It is supposed to go low when 123 outputs a high pulse. \$\endgroup\$
    – Adnan
    Mar 19, 2022 at 4:06


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