74HC04 hex inverter
Six inverters, same package, same rules.
- 14 pins
- 1 setting
- In 1 project
- In 5 lessons
The 74HC04 hex inverter in brief
What it is, and every setting the properties panel gives it.
The 74HC04 packages six independent inverters in one 14-pin chip. Unlike the two-input logic families, its pins alternate input and output all the way down the package instead of grouping by gate, so pin 1 is one gate’s input and pin 2 is that same gate’s output; it is worth checking the pinout rather than assuming the 74HC00’s layout. Pin 14 is VCC and pin 7 is GND, both real pins the chip needs wired before it inverts anything, and its outputs sit high-impedance rather than at a defined level while it is unpowered. An inverter has no controlling-value shortcut the way an AND or OR gate does, since its one input decides the output outright: a known input always gives a known, inverted output, and only a genuinely unknown input gives an unknown one. The datasheet’s typical propagation delay of 9 nanoseconds applies here too, inertially, the same as the rest of the 74HC family Mokxi models.
- Family
- Logic
- Pins
- 14
- model
- 74HC04 (or 74HCT04, 74LS04)
14 pins
Named as the editor names them, so a wire lands where you expect it.
Input6
- 1A
- 2A
- 3A
- 4A
- 5A
- 6A
Output6
- 1Y
- 2Y
- 3Y
- 4Y
- 5Y
- 6Y
Input or output2
- GND
- VCC
How to use a 74HC04 inverter
The 74HC04 holds six NOT gates: each output is the opposite of its input. It is the simplest chip in the 74HC family and a handy way to flip a signal without spending a microcontroller pin or a line of code.
In the traffic light here, the crossing’s request button pulls pin 2 to ground, and the same line goes into one inverter. When the button is pressed the input goes low, so the inverter’s output goes high and lights the WAIT lamp at once, without the Arduino doing anything.
The 74HC14 is the same six inverters with Schmitt-trigger inputs, the better choice for a slow or noisy signal such as an RC delay or a long wire.
What is true about the 74HC04 hex inverter, here
In its help article’s own words: what the simulation gets right, and where it stops.
74HC04: hex inverter
The 7404: six independent inverters sharing one supply. Unlike the two-input
packages, it alternates input and output down each row (pin 1 is 1A, pin 2 is
1Y), so its pin table is worth reading against the datasheet rather than assumed
from the 7400. Propagation delay: 9 ns typical. See it in: Traffic light.
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.
See the 74HC04 hex inverter in a project
One built-in project uses it. It opens in the editor, already wired.
Where it turns up in a lesson
5 lessons place it in their own circuits.
The boards it is shown on
This board has a built-in project with the 74HC04 hex inverter in it.
The rest of the bench
Every one of these is drawn and simulated the same way.
Wire up the 74HC04 hex inverter
Open the editor and push it into the breadboard. It is free, and it runs on your own machine.