demultiplexer
Demultiplexer Tutorial: 1-to-4 and 1-to-8 (DEMUX)
TL;DR: A demultiplexer (DEMUX) is a combinational circuit that takes one data input and routes it to one of output lines, with the destination chosen by an n-bit select code....
Tag
combinational-logic
A collection of 9 posts
comparator
Digital Comparator Explained: Equality and Magnitude
TL;DR: A digital comparator is a combinational circuit that compares two N-bit binary numbers and outputs whether they are equal, or which one is larger. An equality comparator is built...
alu
How an ALU Works: Arithmetic Logic Unit from Gates
TL;DR: An Arithmetic Logic Unit (ALU) is a combinational circuit inside a CPU that performs arithmetic operations (addition, subtraction) and bitwise logic operations (AND, OR, XOR, NOT, shifts) on two...
priority-encoder
Priority Encoder Explained: 4-to-2 and 8-to-3
TL;DR: A priority encoder is a combinational circuit that takes N input lines and outputs a -bit binary code identifying the highest-priority active input. Unlike a plain encoder (which assumes...
combinational-logic
Static vs Dynamic Hazards in Combinational Logic
TL;DR: A static hazard is a momentary glitch on an output that should have stayed constant; a dynamic hazard is multiple transitions on an output that should have changed exactly...
boolean-algebra
Product of Sums (POS): Boolean Form for Efficient Logic
TL;DR: Product of Sums (POS) is the dual of Sum of Products: instead of ORing minterms for the 1s of a truth table, you AND maxterms for the 0s. POS...
combinational-logic
Decoders and Encoders: Driving a 7-Segment Display
TL;DR: A decoder converts an n-bit input into one of one-hot outputs. An encoder does the inverse. A BCD-to-7-segment decoder is a special case: it activates multiple outputs at once...
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...
karnaugh-maps
Karnaugh Maps: Visual Boolean Simplification
TL;DR: A Karnaugh map (K-map) arranges a truth table into a Gray-coded 2D grid where adjacent cells differ by one variable. Grouping adjacent 1s into rectangular powers-of-two produces minimal Sum-of-Products...
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