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  • I assume you need the level shift... because your driving mc pin is not 5V safe... but you do not want the inversion, do you?

    You need now to convert your inverting circuitry in a non-inverting level shifter... and with you PCB already done, you get out of this only with 'fix-wiring-in-the-air' and trace cutting... latter may be prevented...

    Give these approaches a shot:

    First is a bit a hack... The diode in the second is to make sure that the voltage on the input side is lowered, but has a negative inpact on the output, which raises the LOW... between 0.2V at lowest without Diode, and about 0.9 with Diode... To compensate for the first Diode, you may add one in the output as well in forward direction AND add a 33..68K resistor to ground... but that's a lot of stuff in the air...

    Second is a typical MOSFET level shifter.

    As a third, you may also use a 2-transistor - double inverter - after all you may just have all additional components at hand anyway ;-) - with:

    • no trace cutting
    • T1-Base on PCB (instead of T2-Base)
    • T2-Emitter and Collector on PCB (as originally)
    • R2-in-the air with one end on R3-+rail
    • R2-in-the air with non-rail, T1-Collector and T2-Base in the air
    • T1-Emitter somewhere on Ground / T2-Emitter

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