circuitry

noun3

1. •
   A specific system of electrical circuits in a particular device; (uncountable) the design of such a system.

   • Telemetering transmitter removed from its pressurized container. The circuitry for each of the 23 channels can be quickly unplugged for servicing. — 1947
2. •
   Electrical (or, by extension, other) circuits considered as a group.
3. •
   (figurative) The brain's neural network.