1.Below is a screenshot of a good MUX versus bad MUX tested with the same option combinations, the bad MUX output indicates a shorter logic high during the detection time and there is also anomaly at the MUX output during the start-up. The input voltages to the MUX have no anomalies where these input ID voltages tells the MUX how many options the unit have and converted to logic and the synthesizer processor reads the MUX output and more options means longer pulse duration when the unit turns on and display the installed options after.
2.Input pins 4-12 are connected to input ID lines which are driven with a DC voltage (HIGH indicates an option or part is connected, LOW indicates an option or part is not connected). The Enable pin (2) and A0, A1, A2 pins (1, 15, 16) are driven by a separate programmable part which controls which input line we want see at the output. The output pin then goes through a buffer and to an ADC, after which the output is processed by the programed part.
When monitoring the MUX output directly (pin 8), as the enable and selection bits (A0, A1, A2) are changed, the graph shown below was gathered. The top trace is a the output of a functional chip, and the bottom trace is the output of a non-functional chip