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CD4023 triple input NAND gate

Mostly if you want to set up conditions for something to happen electronically then it's pretty normal these days to reach for a cheap microcontroller and with a few lines of code the job is done. For instance, imagine that you need a light in a car to be "ON" (lit) if one or more doors are open. It is quite a simple program, no dramas.

BUT, imagine there is a worldwide shortage of microcontrollers and all that you have are a few logic chips in the bottom of a component bin. In particular, you see a CD4023 triple input NAND gate.

If we look at the logic table and connect up the chip correctly, can we not use this to set up the required conditions, just like the old days?

Of course! So in this circuit I use an 8-way dip switch to simulate a car door opening or closing (6V coming in through a 1k resistor indicating closed or "1").

The CD4023 is configured such that 5 doors of our imaginary hatchback must be closed before the "alarm" output LED is doused. Well, you can see how well it works in the following video.