Applications of Flip Flop

Digital electronics is a very important branch of engineering used for circuit design and data storage. Flip Flops are an important part of digital electronics and are widely used for different purposes. In this article, we will study what are flip flops and the principles used in the working of flip flops. We will also see the applications of flip-flops through certain examples. Later we will discuss the advantages and disadvantages of flip-flops. The article will conclude with a discussion about the future trends of flip flops.

Table of Content

What is a Flip-Flop?

Flip Flops can be understood as a device that helps to maintain a certain state of the circuit unless any input is given to change the state. Flip Flop is termed as the basic memory unit of digital memory because it can store two states, high(‘1’) and low (‘0’). There are various flip-flops like D flip-flops , JK flip-flops, and T flip-flops. Let us now see the working of flip-flops.

Types Of Flip Flops

Let us study the different types of flip-flops

D Flip Flop

These are basic flip-flops used in appliances like counters . There are two inputs to the D flip flop, one is D and the other is D’. Corresponding to this input, an output is generated which changes with the clock pulse. Let us understand this using a truth table.

SR Flip Flop

SR flip flop is most common because it is very simple to design and easier to understand. It consists of two inputs namely ‘Set’ and ‘Reset’ pin and it has corresponding output pins Q and Q’. When the input of ‘S’ pin is high, the output ‘ is high and Q’ is low. Let us understand this with the truth table of this flip flop.

JK Flip Flop

JK flip flop is made by adding some advancements in SR flip flop. It is made specially to design the case where J=1 and K=1. In case, when the inputs applied to the flip flop are different, the output is the value of input J and when the inputs are same ( when J and K are both high) then the output toggles from one state to another. Let us understand this from the truth table.

T Flip Flop

T flip flops are similar to JK flip flop except that they have one input instead of two. In this, J and K are connected together and the output changes accordingly as the clock pulse is provided as an input. Let us understand this from the truth table.

Working Principle of Flip Flop

Let us understand the working principle of flip-flop using the example of a simple D flip-flop.

A D Flip Flop has been shown in the diagram above. This flip flop consists of two inputs one of which is data input and the other is clock input. Corresponding to these two inputs are two outputs Q and Q’ (Q-complement). Now let us see the principle of operation.

Principle of Flip Flop

The flip flop is present in a certain state which is termed as the rest state of the flip flop. Let us consider that the initial state is when Q is 0 and Q’ is 1.

The data input is then used to decide the next state of flip-flop, this state will be triggered when a clock signal is given. The D high is the ‘set’ state and the D low is the ‘reset’ state. It is important to note that flip-flop doesn’t take input continuously, the clock is used to determine when the input data is taken. The flip-flop will change the state when the clock transitions from high to low depending on the data input.

According to the input, the output Q and Q’ get updated. The “set” transition state makes Q high and Q’ low. This is the reverse for the “reset” state. The output has been shown in the truth table above. This is how a flip-flop operates.

Applications of a Flip-Flop

Let us see some applications of flip-flop

• Flip Flops are used as the basic storage unit in digital electronics . They have the ability to store different states in a circuit making them the basic block. They are termed as storage registers and can store data in terms of ‘0’ and ‘1’. Therefore multiple flip flops can be used to store large data bits used in electronics engineering.
• Flip Flops are used as counters, the term counter indicates a circuit that progressively shows the numbers. These counter circuits are implemented to display binary numbers in sequential order with the help of a clock pulse. Some common counters are counter 2 circuit, counter 4 circuit and even counter 7 circuit.
• One important application of flip flop is its use as Frequency Dividers where they are used to divide the frequency of input signal by a certain factor. By making the appropriate connections at the input and the output terminal of the flip flop, one can easily decide the factor by which the incoming signal frequency will be divided.
• Flip Flops also find their application in digital signal processing which is very crucial in electronics. In DSP, flip flops are used for data sampling , buffering, and synchronization of data. The ‘toggle’ feature of the flip flop is extensively used in digital signal processing since it can help to toggle between the two signal states.
• Flip Flops are largely used as shift registers and for the transfer of data. Shift registers are used to transfer data bits one by one to the next register. By temporarily storing data and then transmitting data when they receive clock impulse, they help to transfer data. This is essentially useful for rotate operations and series-parallel conversions.

Now let’s go through the Examples of flip-flip to understand its applications

Examples of a flip-flop

Let us now understand the applications of flip-flop through certain examples.

• Digital Alarm Clocks: Flip Flops perform the task of storing and controlling the information regarding time in a digital clock. They store all this time-related data in binary form and display it accordingly, the alarm feature can be activated by triggering the clock at the time when it should begin to ring.
• Digital Door Lock: Digital Door locks are devices that can be used to secure certain devices like doors, boxes, etc. Flip Flops play an important role in these door locks where flip flops are used to verify the data entered by intruders to the actual code of the lock. Only when the details entered match, the lock opens giving the user access.
• Digital Thermostat: We know that a thermostat is a device that is used for detecting and sensing temperature. These devices monitor the temperature and change the conditions accordingly like controlling the cooling and heating processes. Flip Flops are also used in these devices to establish proper control.
• Digital Display: Digital display is an important part of digital watches and digital traffic control. Here flip flops are used to store all the available data in binary format and then use this information to display the necessary details like the time or the color of the traffic light.
• Dispensing Machines: Certain dispensing machines like vending machines in hotels, and airports make use of flip flops to store inventory information and the details regarding the money sent by the user. Flip Flops operate in such a way that they ensure accuracy in the execution of tasks.

Advantages of a Flip-Flop

Let us see some advantages of flip-flop

• Flip-flops are essential elements since they can store binary data. They can be therefore used to represent certain states in sequential circuits.
• Flip-Flops provide control over various operations since they can be synchronized using a clock. This synchronization is necessary in digital circuits.
• The simple structure and design of flip-flops make them convenient to use. The simple design makes it easier to integrate one chip into the whole circuit.
• Flip-Flops are versatile and can be used for various purposes. Different flip-flops like D flip-flops, JK flip-flops, and T flip-flops can be combined to make circuits that provide diverse features.
• Flip-Flops are reliable since they can be used over different temperature ranges. They are even compatible with new technologies like TTL, CMOS, and LVCMOS.

Disadvantages of a Flip-Flop

Let us see some disadvantages of flip-flop

• Using flip flops brings unnecessary delay introduced due to the propagation delay of flip flops. This creates a time delay between receiving an input and generating an output.
• The effect of noise can be seen in flip flops. During the transmission of signal, noise can unwantedly affect the state of the flip flop resulting in wrong outputs.
• Flip Flops use power even in a stable state of operation which can lead to unnecessary power wastage. This is mainly due to leakage current making flip flops not the best choice for energy-efficient systems.
• The implementation of a circuit involving flip flops can be complex. As the circuit connections become more complex, it is difficult to synchronize the flip-flops and plan the execution.
• Flip Flops are only useful when it comes to storing binary data. This means that they are only capable of executing sequential logic and can’t serve the functionalities of devices like microprocessors.

Future Trends

The future trends of Flip Flop aim at working on certain aspects of flip flops that can help in the advancement of features of flip-flops. It is necessary to keep the flip-flops updated with the development of technology.

Some potential scope of improvement in flip-flops can be miniaturization in the design of flip flops. Developers are trying to design flip flops that can provide more functionalities than current flip flops and at the same time, they utilize less space. Nanotechnology is an important field that will help to achieve this miniaturization.

Another important trend can be making flip-flops energy-efficient. This will help in the reduction of energy consumption thereby resulting in optimized flip-flops. Some other important features that can be taken care of include increasing the operating speed of flip-flops to reduce delay and introducing the feature of operating flip-flops using programming languages.

Conclusion

We have seen how flip-flops form an integral part of digital electronics. Right from circuit designing to data storage, flip flops are used widely in different fields and have numerous applications. Despite the different uses of flip flops, there are some limitations of using flip flops which have been discussed in the article. The article also tries to cover the advancements that can be achieved in flip-flop design to improve the performance of flip-flops. Readers are advised to read the article in case of any doubts.

Applications of Flip Flops – FAQs

Is the flip flop same as a latch?

No, latch is different from flip flop in terms of the transition. In latch, the output changes as soon as input changes (level-triggered) whereas, in a flip flop the output changes only when signal goes from high to low or vice-versa (edge-triggered).

What is a truth table of a flip flop?

Truth Table is table that is used to show the different outputs generated when different inputs are applied across the inputs of flip flops.

What are some different types of flip-flops?

Some commonly used flip flops are D flip-flops, JK flip-flops, SR flip-flops, and T flip-flops.