IC 7400 Working and Its Applications

IC 7400 is the most popular logic family in integrated circuits. Texas Instruments has introduced the first logic chip namely SN5400 series TTL (transistor-transistor logic) in the year 1964. Later on, SN7400 series logic chip was introduced in the year 1966. These chips were gained above 50% of the logic chip market quickly. Finally, these ICs are becoming consistent electronic components. In the past decade, there are different pin-compatible generations with descendant families were developed to give support for lower-power supply voltages, low-power CMOS technology, & surface-mount packages. This article discusses an overview of IC 7400.

What is IC 7400?

The IC 7400 can be built with a number of devices, which provides all from basic logic-gates, FFs (flip-flops), counters to ALU, and bus transceivers. The extended family of digital ICs is 7400 series ICs. This series ICs mainly include different discreet logic chips like logic gates along with different registers, RAM units, and decoders.

The IC 7400 is a 14-pin chip and it includes four 2-input NAND gates. Every gate utilizes 2-input pins & 1-output pin, by the remaining 2-pins being power & ground. This chip was made with different packages like surface mount and through-hole which includes ceramic (or) plastic dual-in-line and flat pack.

ic- 7400
ic- 7400

IC 7400 Pin Configuration

The pin configuration of 7400 IC is discussed below.

  • Pin1: It is an A-input Gate-1
  • Pin2: It is B-input Gate-1
  • Pin3: It is Y-output Gate-1
  • Pin4: It is an A-input Gate-2
  • Pin5: It is a B-input Gate-2
  • Pin6: It is a Y-output Gate-2
  • Pin7: It is a GND terminal
  • Pin8: It is a Y-output Gate-3
  • Pin9: It is a B-input Gate-3
  • Pin10: It is an A-input Gate-3
  • Pin11: It is a Y-output Gate-4
  • Pin12: It is a B-input Gate-4
  • Pin13: It is an A-input Gate-4
  • Pin14: It is a Vcc pin (Positive Supply)

IC 7400 Specifications

Some of the specifications and features of 7400 IC include the following.

  • The voltage supply is 5 V
  • Propagation delay for each gate will be 10 ns
  • Maximum toggle speed is 25 MHz
  • Power utilization for each gate is 10 mW
  • Independent 2-i/p NAND Gates- 4
  • The output can be interfaced with TTL, NMOS, CMOS.
  • The range of operating voltage will be large
  • Operating conditions are extensive
  • Not suitable for new designs which use 74LS00
  • Using 7400 family-based integrated circuits, an engineer can design flip-flops (FFs), counters, buffers, and logic gates in different packages, and these can be connected as preferred to solve an exact problem.

7400 Family IC’s

Some of the most commonly used 7400 family ICs with their functions are discussed below.

  • IC 7400 is a Quad two-input NAND-gat
  •  IC 7402 is a Quad two-input NOR-gat
  •  IC 7404 is a Hex Inverter
  •  IC 7408 is a Quad two-input AND-gate
  • IC 7432 is a Quad two-input OR-gates
  • IC 7447 is a BCD – 7-segment display driver or decoder
  • IC 7474is a twin D-type +ve edge-triggered FF’s
  • IC 7470 is a 4-bit decade counter
  •  IC 7486 is a Quad two-input XOR-gate
  •  IC 7490 is a 4-bit decade counter
  • IC 74138 is a 3-to-8 decoder
  • IC 74153 twin 4-1 multiplexer
  • IC 74157 is Quad D-type FFs with opposite o/ps
  • IC 74160 is a 4-bit binary synchronous counter
  • IC 74164is an 8-bit parallel-out serial shift register
  • IC 74174 is a Quad D-type FFS with opposite o/ps
  • IC 74193 is a 4-bit synchronous up or down binary-counter
  • IC 74245 is an octal bus TX/RX with 3-state output
  •  IC 74266 is a Quad two-input XNOR-gate
  •  IC 74373 is an Octal D-type clear latch
  • IC 74374 is an Octal D-type FF’s

The above mentioned ICs are some of the 7400 families based ICs. Other types of 7400 series ICs are not useful in all cases but they are used rarely. These ICs are used separately to design current digital electronics. But, the above mentioned ICs are easily available in the market and these can be found in an extensive variety of digital designs like low-end devices to high-tech devices.

IC 7400 Circuit Diagram using NAND Gate

The 7400 IC using NAND gate is most generally used transistor-transistor-logic (TTL) device. It can be built with 4-independent 2-input NAND gates.

The main feature of this is that any type of logic gate can be designed with the help of only NAND gates. Thus, IC7400 is suitable to learn regarding digital logic & a universal-spare while particular logic functions are required.


The main function of NAND-gate is when all the inputs are high (1) or low (0), then only the output will be high (1). The function of this logic gate is complementary or opposite to AND gate.

The Boolean expression of this gate is logic addition which is reverse to the AND gate. For example, if the logic expression of AND gate is A*B, then the logic expression of the NAND gate is A*B’. The frequently used logic gate IC is IC 7400 with AND gate. This logic gate includes 4-independent NAND gates by typical pin arrangement. It can operate at 70 o C temperature.


The applications of IC 7400 include the following.

  • These ICs are used to design a system like theft or burglar alarms
  • These are used in freezer warning buzzer
  • These are used in theft alarms activated by light
  • These are used in an automatic watering system

Thus, this is all about an overview of IC 7400. This is a small scale integration (SSI) package. This IC can be built with 4 dual-i/p NAND gates. Because, by using this gate, any type of logic gate can be designed. Here is a question for you, what is the main function of IC 7400?