The Glue Logic Toolbox#
This is the section that most books leave out. Instead of organizing by chip — here is the 74HC595, here is what it does — it organizes by problem. A working engineer rarely thinks “I want a shift register”; they think “I need more outputs than my microcontroller has pins.” This part maps the problem to the part that solves it.
Quick reference#
| I need to… | Reach for |
|---|---|
| one inverter | 74HC04, or 74LVC1G04 (single-gate) |
| debounce a signal | 74HC14 (Schmitt inverter) |
| more outputs | 74HC595 (serial-in, parallel-out) |
| more inputs | 74HC165 (parallel-in, serial-out) |
| switch analog signals | 4066 (quad analog switch) |
| one of eight sensors | 4051 (8-channel analog mux) |
| level shifting | 74LVC, TXS, TXB |
| a reset delay | 555, an RC network, or a supervisor IC |
Each entry expands into its own page with the reasoning, alternatives, and gotchas.