Components

74HC595 pinout and how it turns 3 microcontroller pins into 8 extra outputs, plus the latch-pulse mistake that trips up almost everyone.

CD4017 pinout, why its outputs aren’t in numeric pin order, and how it pairs with a 555 for the classic LED chaser circuit.

LM741 pinout, why it needs a split supply unlike the LM358, and where offset null and slew rate actually matter.

L298N breakout board pinout, wiring, and the onboard 5V jumper mistake that damages a lot of these boards early on.

2N2222 pinout for the modern TO-92 package, why it’s usually a PN2222A underneath, and what changes on the older metal-can version.

LM358 pinout, why its single-supply design differs from a classic split-supply op-amp, and where it trips people up.

LM386 pinout, how its gain-setting pins work, and a minimal wiring for a battery-powered speaker amp.

A pinout reference for the 7805 linear voltage regulator, including typical capacitor wiring and heat considerations.

555 timer pinout, how the internal comparators and flip-flop actually work, and the wiring mistakes that stop it oscillating.