Breadboard simulator
A 400-point breadboard whose strips connect the way real ones do: five-hole rows, power rails along the edges, and parts whose legs sit in the holes (or do not, if you miss). Jumper wires, Dupont leads and the breadboard's own loose contacts have their resistance, so a high-current circuit on a breadboard shows its sag and its hot wires. From the breadboard, lay the circuit out on a perfboard and solder the back, or on a printed circuit board with routed copper, and run it on the same solver. A 3D view shows the board from any angle with the legs in their holes.
Open the labFree, in your browser, no account needed. Part of a free electronics simulator with 293 parts, 193 lessons and 66 builds.
What you can do
- The first circuits of the Fundamentals course are built on it: battery, switch, resistor, LED, then transistors and ICs.
- Learn which rows are joined before you plug in, by hovering a hole.
- Move from breadboard to perfboard to PCB without rebuilding the circuit.
- Find out why a breadboard is not for high current: watch a contact or a jumper heat up.
Builds (7)
18650 battery level indicator
Three LEDs show full, half and low.
555 delay-off timer with relay
Switches a load off after a set time.
PWM fan or LED dimmer
Variable brightness or speed from a knob.
Water-level indicator
LEDs show tank level through probe wires.
LM386 speaker amplifier box
Small amplifier for a phone or radio.
3. Potentiometer: a dimmer
Step 3 of the automatic light: VR1 (10 k) between the switch and R1. Knob at 0: about 15 mA. Knob at the far end…
12. 555 timer: stay on after they pass
Step 12 of the automatic light: The PIR now drives Q2 as an inverter, pulling TRIG low while it sees movement (R8…
Lessons (2)
Perfboard: make every connection yourself
A breadboard joins each 5-hole strip for you. A perfboard joins nothing: every hole is its own island until you solder…
Arduino Nano on a breadboard: a servo sweep
The Nano is an Uno shrunk to 45 × 18 mm, with the same ATmega328P. The Servo library makes 50 Hz pulses on any pin…
Parts (24)
Resistor (CFR-25)
Carbon film · 0.25 W
Potentiometer
Rotary · 10 kΩ linear
Photoresistor (LDR) (GL5528)
GL5528 CdS light-dependent resistor · 14 kΩ at 10 lux · 1 MΩ dark · γ 0.6 · 100 mW
Electrolytic capacitor
Aluminium · 470 µF 25 V · polarised
Supercapacitor
10 F 2.7 V EDLC cell · ESR 75 mΩ · ±20 %
Film capacitor
Polyester box · 1 µF 100 V · non-polarised, fine for AC
Toroidal inductor
Ferrite toroid · 1 H · DCR 8 Ω
Ceramic capacitor
X7R multilayer (MLCC) · 100 nF 50 V · non-polarised, very low ESR
Variable capacitor
Air-dielectric tuning capacitor · 10 pF – 365 pF · now 187 pF
Axial choke
Ferrite-core inductor · 100 µH · DCR 350 mΩ · saturates near 900 mA
Ferrite bead
Ferrite bead · 120 Ω at 100 MHz · 0.03 Ω DC · 3 A · blocks high-frequency noise, passes DC
Quartz crystal
32.768 kHz watch crystal · series resonance 32.768 kHz · C0 1.3 pF · simulated Q 2000 (real…
NTC thermistor (MF52)
10 kΩ NTC sensor (MF52) · R25 10 kΩ · B 3950 K · resistance falls as it warms
PTC thermistor
Switching PTC · 25 Ω cold · switches at 80 °C · resistance climbs steeply above it (motor start…
MOV varistor
14D471K metal-oxide varistor · 470 V at 1 mA · clamps surges, absorbs about 70 J · use across…
Aged electrolytic
Aluminium electrolytic that has dried out with age and heat · marked 470 µF 25 V · ESR 2 Ω (a new…
Breadboard
Half-size solderless breadboard · 30 columns × a–j + 2 power rails each side
Perfboard
Prototype board 24 × 18 holes · 2.54 mm pitch · FR-4, plated through-hole pads on both sides · no…
Via
Plated via · 1 mm pad, 0.5 mm drill · joins top and bottom copper
Printed circuit board
2-layer FR-4 board 102 × 66 mm · 1.6 mm · 1 oz copper · 0 nets from the schematic · showing the…
DC barrel jack
Panel / breadboard jack · 5.5 × 2.1 mm · centre pin + · 5 A
USB-A receptacle
USB-A receptacle (female), through-hole · pins VBUS, D−, D+, GND · a phone plugged in checks…
Wall outlet
Duplex universal outlet · 2 sockets on one 16 A rating · 250 V · neon indicator
Net meter
Bi-directional kWh meter · 1000 imp/kWh
Calculators
LED resistor calculator
The series resistor for one LED or a string
Series and parallel resistor calculator
Total resistance of resistors in series or in parallel
Resistor colour code calculator
Read a 4-band or 5-band resistor
Also on the lab
Solar PV simulator · Battery and BMS simulator · ESP32 simulator · Arduino simulator · House wiring simulator · PCB layout and perfboard · Brownout backup · Piso Wi-Fi on solar · Questions answered · Compared with other simulators