Circuit Simulation Playback

Watch Digital Circuits Build Themselves

SimCast is interactive circuit simulation playback — choose a lesson, hit play, and watch every component appear, every wire connect, and every signal propagate. Each step narrated. Every moment explorable.

78+ Lessons
3701+ Animated Steps
100% Browser-Based

How SimCast Works

Each lesson guides you through building a real circuit — no prior experience needed.

1

Press Play

Choose a lesson and hit play. The simulator opens with an empty canvas, ready to build.

2

Watch It Build

Components appear, wires connect, and the circuit assembles itself step by step — with narrated explanations.

3

See It Run

Signals flow, gates toggle, and you see the circuit working in real time. Pause and explore at any point.

Pro

Pro Lessons

Dive deeper — advanced circuits, memory systems, ALU design, and full CPU architecture.

Lesson 1: Introduction to Digital Signals lesson preview Pro

Lesson 1: Introduction to Digital Signals

34 steps
Lesson 2: Binary Number System lesson preview Pro

Lesson 2: Binary Number System

42 steps
Lesson 3: Two's Complement lesson preview Pro

Lesson 3: Two's Complement

44 steps
Lesson 4: The NOT Gate (Inverter) lesson preview Pro

Lesson 4: The NOT Gate (Inverter)

37 steps
Lesson 5: The AND Gate lesson preview Pro

Lesson 5: The AND Gate

47 steps
Lesson 6: The OR Gate lesson preview Pro

Lesson 6: The OR Gate

47 steps
Lesson 7: Building Simple Circuits lesson preview Pro

Lesson 7: Building Simple Circuits

56 steps
Lesson 8: The Buffer Gate lesson preview Pro

Lesson 8: The Buffer Gate

34 steps
Lesson 9: The NAND Gate lesson preview Pro

Lesson 9: The NAND Gate

44 steps
Lesson 10: The NOR Gate lesson preview Pro

Lesson 10: The NOR Gate

49 steps
Lesson 11: The XOR Gate lesson preview Pro

Lesson 11: The XOR Gate

36 steps
Lesson 12: The XNOR Gate lesson preview Pro

Lesson 12: The XNOR Gate

44 steps
Lesson 13: De Morgan's Law I lesson preview Pro

Lesson 13: De Morgan's Law I

41 steps
Lesson 14: Universal NOT Gate lesson preview Pro

Lesson 14: Universal NOT Gate

32 steps
Lesson 15: Universal AND Gate lesson preview Pro

Lesson 15: Universal AND Gate

42 steps
Lesson 16: Universal OR Gate lesson preview Pro

Lesson 16: Universal OR Gate

42 steps
Lesson 17: Boolean Simplification I lesson preview Pro

Lesson 17: Boolean Simplification I

43 steps
Lesson 18: Boolean Simplification II lesson preview Pro

Lesson 18: Boolean Simplification II

40 steps
Lesson 19: Product of Sums (POS) lesson preview Pro

Lesson 19: Product of Sums (POS)

38 steps
Lesson 20: Don't Care Conditions lesson preview Pro

Lesson 20: Don't Care Conditions

33 steps
Lesson 21: Propagation Delay lesson preview Pro

Lesson 21: Propagation Delay

31 steps
Lesson 22: Half Adder lesson preview Pro

Lesson 22: Half Adder

37 steps
Lesson 23: Full Adder lesson preview Pro

Lesson 23: Full Adder

53 steps
Lesson 24: 4-Bit Ripple Carry Adder lesson preview Pro

Lesson 24: 4-Bit Ripple Carry Adder

64 steps
Lesson 25: Half Subtractor lesson preview Pro

Lesson 25: Half Subtractor

42 steps
Lesson 28: Overflow Detection lesson preview Pro

Lesson 28: Overflow Detection

29 steps
Lesson 29: 2-Bit Binary Multiplier lesson preview Pro

Lesson 29: 2-Bit Binary Multiplier

67 steps
Lesson 30: 4-Bit Magnitude Comparator lesson preview Pro

Lesson 30: 4-Bit Magnitude Comparator

59 steps
Lesson 30: 1-Bit Magnitude Comparator lesson preview Pro

Lesson 30: 1-Bit Magnitude Comparator

50 steps
Lesson 31: 2-to-1 Multiplexer lesson preview Pro

Lesson 31: 2-to-1 Multiplexer

31 steps
Lesson 32: 4-to-1 Multiplexer lesson preview Pro

Lesson 32: 4-to-1 Multiplexer

43 steps
Lesson 33: 8-to-1 Multiplexer lesson preview Pro

Lesson 33: 8-to-1 Multiplexer

60 steps
Lesson 34: 1-to-4 Demultiplexer lesson preview Pro

Lesson 34: 1-to-4 Demultiplexer

67 steps
Lesson 35: 2-to-4 Decoder lesson preview Pro

Lesson 35: 2-to-4 Decoder

46 steps
Lesson 36: 3-to-8 Decoder lesson preview Pro

Lesson 36: 3-to-8 Decoder

72 steps
Lesson 37: Priority Encoder lesson preview Pro

Lesson 37: Priority Encoder

37 steps
Lesson 38: Binary to Gray Code Converter lesson preview Pro

Lesson 38: Binary to Gray Code Converter

72 steps
Lesson 39: Gray Code to Binary Converter lesson preview Pro

Lesson 39: Gray Code to Binary Converter

77 steps
Lesson 40: 4-Bit Parity Checker lesson preview Pro

Lesson 40: 4-Bit Parity Checker

62 steps
Lesson 40: 4-Bit Parity Generator lesson preview Pro

Lesson 40: 4-Bit Parity Generator

77 steps
Lesson 41: Introduction to Sequential Logic lesson preview Pro

Lesson 41: Introduction to Sequential Logic

32 steps
Lesson 42: SR Latch (NOR-Based) lesson preview Pro

Lesson 42: SR Latch (NOR-Based)

43 steps
Lesson 43: SR Latch (NAND-Based) lesson preview Pro

Lesson 43: SR Latch (NAND-Based)

44 steps
Lesson 44: Gated SR Latch lesson preview Pro

Lesson 44: Gated SR Latch

56 steps
Lesson 45: The Clock Signal lesson preview Pro

Lesson 45: The Clock Signal

43 steps
Lesson 48: D Flip-Flop lesson preview Pro

Lesson 48: D Flip-Flop

40 steps
Lesson 49: JK Flip-Flop lesson preview Pro

Lesson 49: JK Flip-Flop

44 steps
Lesson 50: T Flip-Flop lesson preview Pro

Lesson 50: T Flip-Flop

38 steps
Lesson 51: Flip-Flop Preset and Clear lesson preview Pro

Lesson 51: Flip-Flop Preset and Clear

44 steps
Lesson 52: Master-Slave Flip-Flop lesson preview Pro

Lesson 52: Master-Slave Flip-Flop

36 steps
Lesson 53: Introduction to Registers lesson preview Pro

Lesson 53: Introduction to Registers

62 steps
Lesson 54: Shift Register (SIPO) lesson preview Pro

Lesson 54: Shift Register (SIPO)

43 steps
Lesson 55: Shift Register (PISO) lesson preview Pro

Lesson 55: Shift Register (PISO)

46 steps
Lesson 56: Asynchronous Counter lesson preview Pro

Lesson 56: Asynchronous Counter

51 steps
Lesson 57: Synchronous Counter lesson preview Pro

Lesson 57: Synchronous Counter

43 steps
Lesson 59: Ring Counter lesson preview Pro

Lesson 59: Ring Counter

60 steps
Lesson 60: Johnson Counter lesson preview Pro

Lesson 60: Johnson Counter

49 steps
Lesson 62: Counter Applications lesson preview Pro

Lesson 62: Counter Applications

36 steps
Lesson 63: RAM Cell (SRAM) lesson preview Pro

Lesson 63: RAM Cell (SRAM)

40 steps
Lesson 64: Memory Organization lesson preview Pro

Lesson 64: Memory Organization

42 steps
Lesson 65: Sequence Detector lesson preview Pro

Lesson 65: Sequence Detector

60 steps
Lesson 66: Traffic Light Controller lesson preview Pro

Lesson 66: Traffic Light Controller

45 steps
Lesson 68: Program Counter lesson preview Pro

Lesson 68: Program Counter

49 steps
Lesson 70: Control Unit Basics lesson preview Pro

Lesson 70: Control Unit Basics

64 steps
Pro

Level 2 Review: 4-Bit Calculator

70 steps
Pro

NOR Logic Implementation

54 steps
Pro

NAND Logic Implementation

55 steps
Pro

Logic Levels and Thresholds

22 steps
Pro

Circuit Optimization II

31 steps
Pro

Circuit Optimization I

36 steps
Pro

Sum of Products (SOP)

83 steps
Pro

Parity Generators and Checkers

50 steps

Unlock all 72+ Pro lessons with DigiSim Pro

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