sequential-logic
Mastering Sequential Logic: The D Latch Explained and Simulated
TL;DR: A D latch stores one bit. It has two inputs (Data and Enable) and follows the characteristic equation . When Enable is HIGH, the latch is transparent — Q...
combinational-logic
Multiplexers (MUX) Demystified: The Data Traffic Controller
TL;DR: A multiplexer (MUX) selects one of data inputs and routes it to a single output, controlled by select lines. The Boolean expression for a 4-to-1 MUX is . A...
sequential-logic
SR vs. JK Flip-Flops: The Basics of Sequential Logic
TL;DR: The SR latch is the simplest memory element but has a forbidden state when both inputs are 1. The JK flip-flop fixes this by redefining J=K=1 as a toggle,...
and-gate
The AND Gate: Foundation of Digital Logic and Decision Making
TL;DR: An AND gate outputs 1 only when every input is 1; otherwise the output is 0. Boolean expression . Despite the simple logic, real AND gates have non-zero propagation...
clock-signal
The Clock Pulse: Why Computers Need a Heartbeat
TL;DR: A clock signal is a periodic square wave (typically 50% duty cycle) that synchronizes every flip-flop and pipeline stage in a synchronous digital system. Modern CPUs derive multi-GHz clocks...
d-flip-flop
The D Flip-Flop: Edge-Triggered Memory in Digital Design
TL;DR: A D flip-flop captures whatever is on its data (D) input at the moment of an active clock edge and holds that value until the next active edge. Its...
education
The End of the Breadboard? Why Virtual Labs are Here to Stay
TL;DR: Browser-based circuit simulators teach digital-logic concepts faster and more reliably than physical breadboards by collapsing the build-test-revise cycle from minutes to seconds, exposing every signal at every node, and...
arithmetic-circuits
The Half Adder vs. The Full Adder: How Computers Do Math
TL;DR: A half adder sums two single bits to produce Sum (XOR) and Carry (AND). A full adder sums three bits — A, B, and a carry-in — and is...
half-adder
The Half Adder: Your First Step into Digital Logic Design
TL;DR: A half adder is the simplest binary-addition circuit. Two inputs (A, B) produce two outputs: Sum = (XOR) and Carry = (AND). It's only "half" an adder because it...
not-gate
The Humble NOT Gate: Inversion's Power in Digital Logic
TL;DR: The NOT gate (inverter) takes a single input and outputs its logical complement: . It is the third member of the AND/OR/NOT functionally complete set. Beyond simple inversion, NOT...
jk-flip-flop
The JK Flip-Flop: Universal Sequential Building Block
TL;DR: The JK flip-flop is the most versatile 1-bit memory element. Its J and K inputs at the active clock edge select one of four modes — hold (00), reset...
johnson-counter
The Johnson Counter: A Twisted-Ring Counter Explained
TL;DR: A Johnson counter is a synchronous shift register where the inverted output of the last stage feeds back to the first stage. With flip-flops it produces unique states, and...