7400 Series Guide: 74HC04/74LS04 (NOT gates)

This IC, often found as 74LS04 or 74HC04, is a chip with six NOT gates – or inverters. The NOT gate is a logic gate that always gives you the opposite of what you put in. It is one of the most basic building blocks in digital electronics and comes in a 14-pin package with the following pinout:

74HC04 package and pinout

In this guide, you will learn what the 74×04 IC does and how to hook it up in a circuit.

What does the 74HC04 / 74LS04 do?

The 74×04 gives you six inverters that can be used individually. A NOT gate (or inverter) is a logic gate that outputs the opposite of the input. In the truth table below, you can see what the output will be for any given input:

NOT truth table
Truth table for the NOT gate (inverter)

How To Use This Chip

Like every other chip in the 7400 series, this IC must be connected to power before you can use it. Most 7400 ICs support a VCC voltage of 5V. One difference between the HC and LS version of the chip is that the 74HC04 supports 2V to 6V, while the 74LS04 supports only 5V.

Once it’s connected, you can use any of the six inverters inside.

How to connect the 74HC04 to 5V on a breadboard
The 74HC04/74LS04 IC connected to power

Output Current

Each gate output of the 74HC04 can sink or source 4 mA when powered with 5V.

HIGH-Level Output Current: 0.4 mA
LOW-Level Output Current: 8 mA

74×04 Pinout

The 74×04 has 14 pins and contains six inverters laid out as shown in the pinout diagram below:

Pin NamePin #TypeDescription
1A1InputInput to the first NOT gate.
1Y2OutputOutput from the first NOT gate.
2A3InputInput to the second NOT gate.
2Y4OutputOutput from the second NOT gate.
3A5InputInput to the third NOT gate.
3Y6OutputOutput from the third NOT gate.
GND7PowerConnect to ground.
4Y8InputOutput from the fourth NOT gate.
4A9OutputInput to the fourth NOT gate.
5Y10InputOutput from the fifth NOT gate.
5A11OutputInput to the fifth NOT gate.
6Y12InputOutput from the sixth NOT gate.
6A13OutputInput to the sixth NOT gate.
VCC14PowerPositive power supply. Connect to +5V power.
Pin overview for the 74×04 IC

74×04 Circuit Example

A NOT gate can be used for a zillion different things. For example, you can convert an AND gate into a NAND gate, like this:

Equivalent NAND gate built from AND nad NOT gates

Or you could convert an OR gate into a NOR gate, like this:

NOR gate equivalent from OR and NOT

Alternatives and Equivalents for 74HC04 / 74LS04

There are many versions of the 74×04 chip. They all have the same functionality but with different specifications such as supported voltages and maximum current output.

Here’s a list of a few equivalents of this chip:

  • 74HC04 (High-speed CMOS)
  • 74HCT04 (High-speed CMOS, TTL compatible)
  • 74LS04 (High-speed TTL)
  • 74LVC04 (Low Voltage TTL)
  • 74AC04 (Advanced CMOS)
  • 74ALS04 (Advanced Low-Power Schottky TTL)
  • 74F04 (Very High Speed)
  • 74C04 (CMOS, similar to the 4000-series)

Some manufacturers also add a prefix, such as the SN74HC04 and SN74LS04 by Texas Instruments.

Can’t find the 74×04 anywhere? Then try one of the following IC alternatives:

  • 74×05 – Hex inverters (with open-collector outputs).
  • 74×14 – Hex inverters (with Schmitt-trigger inputs).
  • CD4049 – Hex inverting buffers/converter.
  • CD4069 – Hex inverters/NOT-gates.
  • CD40106 – Hex inverters (with Schmitt-trigger inputs).

If you can’t find the 74×04 IC in your local electronics store, don’t worry, you’ll most likely find it in one of the stores listed on this page of online stores where you’ll find components and tools for all your electronics projects.

Datasheet for the 74LS04 and 74HC04 chips

Download the PDF datasheet for your version of the 74×04 here:

4 thoughts on “7400 Series Guide: 74HC04/74LS04 (NOT gates)”

      • Image and table are both wrong. Check out the image in the TI datasheet, page 1, “functional pinout”.

        Pin 8 is an output, pin 9 input. Pin 10 output , pin 11 input, pin 12 output, pin 13 input.

        • Thanks! My script had an error. I’ve updated the pinout image and table. Let me know if you still see any other errors


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