CD4014 8-Stage Static Shift Register IC

The CD4014 is a CMOS logic-based IC belonging to a CD4000 series of integrated circuits. It is an 8-stage shift register with parallel or serial input/ serial output. It has pins for both serial input and parallel inputs. The mode selection pin is available to control the input mode. Moreover, control pins enable inputs to the 8-stage shift register.  This IC make up of flipflops. The common clock signal gives transition signals to all flipflops that’s why they are synchronous with each other. All the inputs are connected to diodes to protect them against static discharges. It is available in 16-pin PDIP, GDIP, PDSO packages.

CD4014 Pinout Diagram

CD4014 is an 8-bit static shift register. It consists of fourteen pins. Out of 14, seven pins are responsible for parallel data input from INPUT PI 1 to INPUT P1 7. Additionally, it has three output pins Q6-Q8. This figure shows a pinout diagram.

CD4014 Pinout diagram 8 stage shift register

Pin configuration Details 

This shift register has 16 pins in total. All these pins, their name, and description are given in the table below.

Pin NumberPin NameDescription
1, 4, 5, 6, 7, 13, 14, 15From INPUT PI 1 to INPUT PI 7Parallel input data pins
2, 3, 12OUTPUT Q6, Q7, Q8Output pins
8VSS (Ground)Ground of the circuit or negative power supply
9INPUT P/SParallel/ serial control input pin
10CLOCKClock pulse/ input signal
11SERIAL INSerial Input data pin
16VDDPositive terminal of voltage supply

 CD4014 Shift Register Features

  • 8-stage parallel input/serial output shift register with 9 input lines and 3 output lines
  • output buffering and control gating
  • Fully static operation
  • Wide voltage supply range of 3-V to 15-V
  • High noise immunity of 0.45
  • Operating Temperature Range is from -55°C to +125°C
  • Propagation delay is 320ns
  • The maximum Leakage input current of 1uA at 15V (over full temperature range)
  • Low Power TTL compatibility

Note: You can refer to the datasheet for more electrical specifications. The link of the datasheet is at the end of tutorial.

Other alternative and Equivalent shift Registers: 74HC595, CD4035,CD4015, CD4014

Where to Use CD4014? 

This IC is just like a parallel to the series converter. It allows you to take multiple values as an input at once and then shift them out by controlling four output pins in parallel. If you want to control many devices through a microcontroller.

For example, LEDs then you can use this IC. CD4014 IC is easy to use. Its connection diagram and the logic diagram are shown below. Its internal structure consists of D-type, master-slave flip-flops. You can see that it has a common clock.

CD4014 8 stage shift register connection diagram

Working Principle

It has a parallel/serial control input pin which is responsible for deciding whether the data shifts into the register in parallel or in a serial manner. When the value of parallel/serial control input is LOW or 0, data is serially shifted into the register. Data sends in parallel mode into each stage when this input is HIGH or 1. The CD4014 shift register has a common clock that is responsible for the shifting of data. At the positive edge of the clock signal, the data is shifted into the registers in serial or parallel manner depending on the state of parallel/serial control input pin synchronously. It has three output pins coming out of the sixth, seventh and eighth stages of flipflops. The logic diagram of the circuit is given below.

 8 stage shift register logic diagram

CD4014 IC can be used for demultiplexing of data. You control the outputs through this IC when you do not have enough GPIO pins on your microcontroller or microprocessor as it provides you with eight parallel input pins and one serial input pin.

CD4014 Simulation Circuit Examples

In the end, we will see two example circuits to better understand the working principle. Proteus has a built-in library of CD4014, we can use this library to design example circuits. Firstly, we will see a parallel data transfer example. After that, we will look into serial data shifting example.

Parallel Data Transfer Example

First of all, we select parallel data transfer by setting the P/S pin to active high. Therefore, a CD4014 shift register will jam the data available on the SIN (pin11) pin. It will only shift data from parallel pins such as D0-D7.

  • At the start, we give input to parallel input pins 00000111. After that as soon as we provide a positive edge of the clock cycle, 111 appears at the output pins. Because most significant three bits develop at the output only.
  • Similarly, we give logic inputs of 00000101 and 00000100. Consequently, respective logic appears at the output pins on every positive clock edge.
CD4014 shift register parallel data transfer example simulation

In short, the advantage of using parallel transfer is that unlike,  data appears at the output in a single clock.

Serial data shifting Example CD4014

In this example, we use the 8-stage static shift register to transfer data to the output pins bit-by-bit. Firstly, we set the P/S pin to logic zero that will select a serial shifting mode. We provide a logic input 00000001 at the input of serial pin. As you can see from the simulation, the output starts to appear on Q6-Q8 pins after the seven clock cycle. Because initially, input signals are active low.

CD4014 shift register SERIAL data transfer example simulation

Applications CD4014 Shift Register

Some of the applications of this IC are:

  • Data queueing is performed through this IC
  • Parallel to serial conversion of data and it is useful in circuits that have to deal with a large number of inputs at a time.
  • General-purpose registers and Arithmetic Logic units (ALU’s)
  • Delay circuits and pulse extenders.
  • Digital memory circuitry such as calculators, computers and data processing systems
  • Communication lines for demultiplexing of a data line

2D Diagram

 2 Dimension diagram

Datasheet

CD4014 Datasheet

Proteus Simulation

CD4014 is a shift register IC,  it can transfer data in serial as well as in parallel mode. In parallel mode, pin D0 to D7 is used as data input pins.  In serial mode, data transferred serially. Serial IN pin is used to transfer data serially.

Pin10 is a clock pin. This IC makes the transition of data on every positive edge of the clock signal. For simulation purposes, We will use a toggle switch to provide a positive edge. Because, switching from zero to one, will provide a positive edge, to shift register.

Pin9  is a mode select pin, that is the P/~S pin. It is used to select either serial or parallel mode. To select parallel mode, set this pin to one. To select serial mode, set this pin to 0.

Q5 to Q7 are output pins. That means, this shift register, only provides three most significant bits, at the output. Now let’s see CD4014  simulation, and how it works in Proteus.

How to use CD4014 in Parallel Mode

  • Click on the proteus play button.
  • First let select parallel mode, by setting pin 9 to logic high.
  • At the start, let’s give input  00000111 to parallel input pins.
  • After that, as soon as, we provide a positive edge of the clock cycle,
  • 111 appears at the output pins.
  • Because, only the most significant three bits, appear at the outputs pins.
  • Similarly, we give two more logics at the parallel data input pins and, observe output pins.
  • Consequently, respective logic appears at the output pins, on every positive clock edge.

How to use CD4014 in Serial Mode

Now let’s see how it works in serial mode.

  • First,  select serial mode by setting pin 9 to logic low.
  • Let’s restart the simulation.
  • Note that, at the start, all output pins, and internal states, are initially set to zero.
  • CD4014 is an 8-bit shift register IC. In serial mode, data transfer bit by bit. 
  • Therefore, if we apply logic one on a serial input pin, it will appear on output pins, after the 5th clock cycle, or on the 6th clock cycle.
  • Because in serial mode, data transfer bit by bit.
  • As you can see,  the logic one appears on Q5 on the 6th clock cycle, and on Q6 on the 7th clock cycle, and so on.
  • Similarly, now let’s apply logic zero, on the serial data input pin. As you can see, logic zero appears on Q5 on the 6th clock cycle, and on Q6 on the 7th clock cycle, and so on.

Other electronics components:

Leave a Comment