Source: https://mokxi.com/parts/74hc86
Updated: 2026-09-27

Part

# 74HC86 quad XOR

Four XOR gates.

or see every part

- 14 pins

Drawn live by the editor's own code, at the size you see it.

Reference

## Every one of its 14 pins

Pin

Role

What it does

1A

Input

1B

Input

1Y

Output

2A

Input

2B

Input

2Y

Output

GND

Input or output

3Y

Output

3A

Input

3B

Input

4Y

Output

4A

Input

4B

Input

VCC

Input or output

This part

## What it does

The 74HC86 packages four independent two-input XOR gates in one 14-pin chip, wired the same pin layout as the 74HC00: pin 14 is VCC, pin 7 is GND, and both have to be wired before any gate does anything. An XOR has no controlling value the way an AND or OR gate does, since either input alone can flip the answer, so an unknown on either input gives an unknown output regardless of the other input’s level. That makes it the odd one out among the logic families Mokxi models, and it is also what makes an XOR the natural core of a binary adder’s sum bit, or of a simple parity check across several inputs. The same 9 nanosecond typical propagation delay applies here, inertially, so a pulse narrower than that time never reaches the output. Wired next to a 74HC00, as it is on the logic gate simulator page, the two chips answer the same two inputs completely differently, which is the whole point of showing them side by side.

How it is modeled

## What is true about the 74HC86 quad XOR, here

### 74HC86: quad 2-input XOR gate

The 7486, same package, four exclusive-OR gates: the adder and parity building
block, and the cheapest way to make a controllable inverter. An XOR has no
controlling value, so any unknown input gives an unknown output. It sits one gate
deeper inside the package than a NAND, so it is slower: propagation delay 12 ns
typical. See it in: Full adder.

### Not modeled

One typical delay, and nothing around it. Each chip carries a single propagation
delay taken from its datasheet's typical column at VCC = 5 V, CL = 15 pF and
25 °C, and uses it for every path through the package. There is no minimum or maximum,
no spread between the gates in one chip, no rise or fall time, no output slew and no
dependence on supply voltage, load capacitance or temperature, all of which a real
74HC part has, and all of which a datasheet gives ranges for. On the 74HC595 the one
figure is the STCP-to-Qn number used for SHCP and MR to Q7S as well, which
the datasheet lists a nanosecond or two apart.

No setup, hold or pulse-width checks. The 74HC74 and the 74HC595 take a clock edge
whenever they see one; nothing here refuses data that changed too close to the edge or
a clock pulse that was too narrow, and nothing warns about it. A real part would
metastable or simply miss.

No supply current, no output current limit and no bus contention damage. An output
driving into another output is resolved as two drivers on one net; nothing gets hot.

Sequential parts power up cleared rather than random, because a toggle divider fed
Unknown never escapes it. See how faithfully a part
behaves.

From The 74HC logic family, in full.

Projects

## See the 74HC86 quad XOR in a project

Learn

## Where it turns up in a lesson

### In the twelve week course

- Week 6: Arithmetic from gates: the full adder

### In a learn article

- Half Adder and Full Adder: Truth Table to Breadboard

More parts

## The rest of the bench

Every one of these is drawn and simulated the same way.

Full-size breadboard

A real 0.1 inch grid with the rails and the center channel, 63 columns wide.

Jumper wires

Drag from any pin or hole to any other. Corners snap, and you can drag them.

Power

A supply rail at the voltage you choose.

Ground

The other end of every circuit.

LED

Lights when current flows. Five colors, and the brightness is what your eye would see.

Resistor

Any value you like, with the color bands drawn to match.

ESP32-C3-DevKitM-1

A RISC-V board that runs your firmware at 160 MHz on the real memory map.

Pushbutton

A 12 mm tactile switch. Hold it while the simulation runs.

Raspberry Pi Pico

The RP2040 board on our own Cortex-M0+ core. Pick a program and press Run.

Raspberry Pi Pico W

Raspberry Pi Pico W (RP2040). The same board and the same pinout as a Pico, with the CYW43439 on it. The WiFi is simulated (no radio, no real internet), and the on-board LED, which hangs off that chip rather than off GP25, is driven through the same path. Everything else is the Pico.

STM32F411 Black Pill

The Black Pill on our own Cortex-M4 core. Pick a program and press Run.

BBC micro:bit V2

The nRF52833 board with its 5x5 LED matrix, buttons A and B and a speaker. Wire the rings to a breadboard.

See every part

## Wire up the 74HC86 quad XOR

Open the editor and push it into the breadboard. It is free, and it runs on your own machine.

Start building Open the editor
