What is Flip flop ?

Flip flop

Flip flop –

“A digital computer needs devices which can store information.”

A flip flop is a binary storage device , it can store binary bit either 0 or 1. It has two stable States : high and low I.e. 1 , 0 .

Or

A basic sequential logic circuit is a flip flop has bistable state or two stable state , first is “0” and second is “1” .

Type of flip flops –

1. R-S flip flop

2. D – flip flop

3. J – k flip flops

4. Master slave J-K flip flop.

Characteristics –

flip flop is a bistable device, it has only two States 0 and 1 .

Flip flop has two outputs , one output is complement of other.

R-S flip flop –

A flip flop is a device with two stable state. It is reset and second is set. The S-R latch is the simplest flip flop. It is also called S-R (R-S) flip flop.

In this circuit one of the transistors it Saturated and the other is cut off.

Symbol of s-R flip flop

We discuss two type of R-s flip flop :

1 Transistor latch

2. diode latch

Transistor latch using :

There are two  control input S and R

1. In first case when S = 0 , R = 0 . Then transistor T1 not working because of forward bias now T2 base find R = 0 and from Q point as 5v voltage. It T2 is saturated the T2 connected to ground and Q connect T2 Then point Q = 0 .

2. Second case R = 0 , S = 1 . S = 1 connect to transistor T1 base point T1 saturated and T1 connect to ground so Q = 0.

Now Q = 0 , R = 0 both value to comes T2 each transistor than T2 not working but transistor T1 connect to Q , so Q = 1

3. Third case R = 1 , s = 0 for value of R = 1 T2 transistor then T2 not working , but transistor T1 connect to Q so We find transistor Q = 1

Third case R = 1 ,S = 0 for value of R , T2 transistor saturated and Q connect to ground Q = 0

Then Q = 0 , s = 0 both values comes for T1 transistor but T1 not saturated Q = 0.

4. Fourth case R = 1 , s = 1 . This is called race condition .

R S Q Comment
0 0 NC NO CHANGE
0 1 1 SET (0)
1 0 0 RESET (0)
1 1 NA NOT ALLOWED

Timing diagram –

Diode latch R-S flip flop –

There are two types of diode latch flip flops –

1. NOR latches

2. NAND latches

NOR latches –

R-S (S-R) flip flop can be constructed with the help of 2 NOR gates which are available as ICs .

Working-

1. Let Q = 0 and Q = 1 in ( initial value) when R=0 and S = 0.

Now the inputs to hence output q = 0
similarly input to the NOR Gate B are S = 0 and q = 0 , then output Q = 1.

Hence no change in the state of ff.

2. when R = 0 , S = 1.

Now the input the NOR gate B are S=0 and Q = 1 the output Q should be 0.

Q = 0

similarly now the inputs to the NOR Gate A are R = 0 and Q = 0 hence it is output Q = 1
hence the result of the FF set .

3. when R=1 , S = 0

Now the input the NOR gate A are R = 1 and Q = 0 then the output Q should be 0 .

Q= 0

similarly now the inputs to the NOR gate B are s = 0 , Q = 0 then the output Q=1

This condition are reset.

4. When both S and R. R = 0 , S= 1
then both the output Q and Q will be forced to be in 0 state.

But Q = 0 and Q = 0 is meaningless

condition are not allowed

Truth table –
R S Q Q Comment
0 0 0 1 NO CHANGE
0 1 1 0 SET
1 0 0 1 RESET
1 1 1 0 NOT ALLOWED

NAND latches –

1. initially let Q = 0 , Q = 1 suppose R = 1 and S = 1 , Then input to the NAND Gate A are S = 1 , Q = 1 , so that the output Q = should be in o state.

Q = 0

similarly the NAND Gate B are R = 1 , Q = 0
Then the outputs becomes Q should be 1 .

Q = 1

The condition is no change.

2. when R = 1 , S = 0.

when the inputs S = 0 and Q = 1 with the NAND Gate A form the output becomes Q should be 0.

Q = 0

similarly the NAND gate B are R = 1 and Q = 0 .

Then the output become Q should be 0.
Q = 1.

3. When S = 1 and R = 0.

Now the gate III condition just opposite. Then it is obvious that the flip flop resets.

I.e. Q becomes 0.

4. when R = 0 , S = 0 .

Then the don’t case condition lead to the result that Q = 1 , Q = 1 , but this is meaningless.

The condition is not allowed.

Truth table –
R S Q Q COMMENT
1 1 0 1 NO CHANGE
1 0 1 0 SET
0 1 0 1 RESET
0 0 1 1 NOT ALLOWED
Timing diagram –

Clocked flip-flop –

“This could be achieved with a modified version of the flip flop called as a clocked RS FF.”

It is very useful to add clock to SR flip flop to shown this figure.

Symbol –

Circuit diagram –

Action Of Clocked R-S Flip Flop-

1. When the clock input (CK) is low condition both the AND Gates are disabled.
Thus their output remains low (0). This makes S1 = 0 and R1 = 0 the state of the FF will not change .

2.When CLK = 1 , then the AND GATES are enabled and the S , R inputs are able to reach at the inputs of the RS FF .

Depending on the states of R and S inputs the flip flops can SET RESET .

All possible states of R and S along with the corresponding state of the output.

Working –

Case I When CLK = 0

1. S = 0 , CLK = 0 , Then S1 = 1 similarly R = 1 , CLK = 0 , R1 = 1 in NAND Gate.

S1 ,R1 NC condition.

2. S = 0 , CLK = 0 then S = 1

And R = 1 , CLK = 0 , Then R1 = 1 NC condition

3. S = 1 , CLK = 0 Then S1 = 1

R = 0 , CLK = 0 Then R1 = 1

4. S = 1 , R = 1 , then NC change.

CASE II . When CLK = 1

1. s = 0 , CLK = 1 Then S1 = 1
R = 1, CLK = 1 Then R1 = 0 and
We know S1 = 1 , R1 = 0 is called reset condition Q = 0

2. S = 1, CLK = 1 Then S1 =0
R = 0 , CLK = 1 Then R1 = 1
and we know S1 = 0 , R1 = 1 is called set condition Q = 1

3. S = 0 , CLK = 1 then S1 = 1
R = 0 , CLK = 1 then R1 = 1 and
S1 and R1 = 1 Then Q = no change.

Truth Table –

CLK S R S1 R1 Q
0 0 0 1 1 NC
0 0 1 1 1 NC
0 1 0 1 1 NC
0 1 1 1 1 NC
1 0 1 1 0 0 (RESET)
1 1 0 0 1 1 (SET)
1 0 0 1 1 NC
1 1 1 0 0 NOT ALLOWED

Timing diagram –

Disadvantage –

1. race condition.

2. level locking (means only one Level work (high).

D flip flop –

“Clocked RS flip flop can be modified to a better version called as D-type flip-flop.”

This flip flop possesses only one data input. The D flip flop is widely used , it is also know as a data or delay flip flop.

Symbol –

Circuit Diagram –

Working –

CASE I .

When D = 1 then S = 1 and R = 0 hence as clock goes high , the flip-flop will be Set or Q will become 1

Q = 1 .

CASE II.

If D = 0 then S = 0 and R = 1 Hence as the clock goes high the flip-flop will RESET
Q = 0

Edge Triggered Flip Flop –

The clock input pulses and corresponding output at the differentiating circuit. This output consists of positive and negative going spikes.

There are two types –

1. Positive edge triggered FF –

The flip-flop responds for 0 to 1 change of the clock pulse such a flip flop is called as a positive edge triggered flip flop.

2. Negative Edge Triggered Flip Flop –

A circuit which respond to 0 to 1 change of the clock pulse or at the fulling edge is called as a negative edge triggered flip flop.

Symbol & Circuit Diagram –

CASE I . When CLK = 0 then each value of D use find the output no change.

CASE II. When CLK = 1

1. When CLK = 1 Then D value do not. Then output find NC condition.

2. IF CLK is falling edge output remains find NC condition.

3. If CLK is rising edge then D = 1 then find output Q = 1 .

4. If CLK is rising edge and D = 0, then find output Q = 0.

Truth Table –

CLK D Q
0 X NC
1 X NC
DOWN X NC
UP 0 0
UP 1 1

Disadvantage –

In this output change only on the rising or falling edge of CLK .

Preset And Clear –

It should be clear that the output of a flip flop changes whenever a clock pulse is applied.

These leads which help to set or clear (reset) the flip-flop are independent of clock . This will be clear form the discussion to follow.

Preset –

Preset is called “direct set” means unclocked.

Clear –

Clear is called “direct reset“.

Working –

1. when preset = clear = 0 then gate P and Q both don’t case their second output is not allowed Q = * .

2. when preset = 0 , clear = 1 then R = 0 , but Q gate depend upon their second input in the NAND Gate latch , don’t care Q = 1.

3. when preset = 1 clear = 0 then S = 0 , so don’t care Q = 1 and similarly Q = 1 (Reset ).

4. when preset = 1 = clear then if CLK = 0 for P gate input are 1 there R = 1 similarly S = 1 then output NC condition.

5.Preset = clear = 1 then CLK = 1
A’ = 0 , Preset = 1 then R = 0
B’ = 0 , clear = 1 then S = 0

6. Preset = clear = 1 then CLK = low
A’ = x then R = 1
B’ = x then S = 1
NC condition.

7. Preset = 1 = clear then CLK = high
D= 0 , CLK = High , A’ = 1 , Preset = 1 , R = 1
And D’ = 1 ,CLK = high, B’ = 0 , clear = 1 , S =0.

8. Preset = 1 = clear then CLK = high
D = 1 , CLK = high , A’ = 0, Preset = 0, R= 0
D’ = 0 , CLK = high , B’ = 1, clear = 1, S = 1
1 set.

Truth table –

Preset clear CLK D Q
0 0 x x *
0 1 x x 1
1 0 x x 0
1 1 0 x NC
1 1 1 x NC
1 1 down x NC
1 1 up 0 0
1 1 up 1 1

Timing Diagram –

Propagation Delay-

Propagation delay is the amount of time taken for the output of a gate.

o

A flip flop to change State after the input changes states. Output changing 0 to 1 and 1 to 0 .

Setup Time –

The setup time t is the minimum time for which the data bit must be present before the clock pulse arrives.

Hold Time –

Hold time is the minimum time for which the data must remain present after the edge of the clock pulse.

J-K flip flop –

“A J-K flip flop is a modification of the R-S flip flop in that uncertain state of the RS type is defined in the JK type.”

Or

“J-K flip flop is an essential building block of sequential circuits such as counters and shift registers.”

The data at the J and K inputs of the JK flip flop controls (set and reset) output.

Symbol & Circuit diagram –

Working –

1. When J = K= 0 (inactive State)
Both J and K = 0 clock pulse has no effect O/P.

Then R = 1 , S =1 then o/p is same NC condition.

2. When J = 0 , K = 1 (reset stage)
When J = 0 the o/p of AND GATE corresponding to J becomes 0.

example – R = 1 , S = 0 then the o/p Q is reset condition means Q = 0.

3. Set state ( J = 1 , K = 0 )
This case Q = 1, the AND gate responding to k becomes 0 ,

example R = 0 and S = 1 Therefore Q = 0 and Q = 1 it is called set condition.
Q = 1

4. Toggle stage

J = 1 , K = 1

In this case R = 0 , S = 0 , toggle Mode.

Truth Table –

CLK J K Q
0 x x NC
1 x x NC
Down x x NC
X 0 0 NC
Up 0 1 RESET (0)
Up 1 0 SET (1)
Up 1 1 Toggle (0)

Timing Diagram –

In RS flip flop S = R = 1 gives unpredictable state of the output. In a JK flip flop J = k = 1 is permissible. In this condition the state output is changed , complement of the previous state is available .

If in the previous stage Q is 0 it becomes 1 and vice versa :

If a JK flip flop is level triggered ,the output is not stable with J = K = 1 so long as the clock is high . The output goes on changing its State to avoid such oscillations an R-C circuit is incorporated in the clock input circuit to make a J-K flip flop edge triggered , gives stable o/p.

Master slave JK flip flop –

“A JK master slave flip flop consists of two Gates or clocked RS flip flops called as a master and a slave.”

Output of the second flip flop (slave) is (fed) back to the input of the first (master) as shown fig .

When clock is high master is active and slave is inactive.

When clock is low master inactive but slaves is active.

Symbol and Circuit diagram –

Working-

1. Set Conditions –

J = 1 , K = 1 and clock = high , if Q = 0 , Q = 1 (previous state) then master will set in R = 1, S = 0 and slave will inactive .

When clock = low

In case master inactive but slave FF active and find input R = 1, s = 0 then R’ = 0 , S’ = 1 and output Q = 1 , Q = 0 , it is called set condition .

2. Reset Conditions
J = 0 , k = 1 clock = high in preset condition Q = 1, Q = 0 of flip flop.

During the high clock signal master will reset R = 0 , S = 1 but output remains same ( in preset condition Q = 0 ,Q = 1 ) as the slave will be inactive when clock is low .

When the clock signal is low : then master will be inactive and slaves be active so flip flop remains find reset it means Q = 0 , Q = 1.

Toggle condition –

J = K =1
In this above condition Q = 0 , Q = 1 (pre) condition of flip flop.

During the high clock signal master will toggle (means R = 0 , S = 1) so R= 1 , S = 0 and output remains same (Q = 0 , Q = 1) as the slave will be inactive when clock is high.

when low clock signal arrives master will be inactive and slave will be active which toggle the flip-flop output Q = 1 , Q = 0.

Truth table –

CLK J K Q Q COMMENT
1 1 0 1 0 SET
1 0 1 0 1 RESET
1 1 1 1 0 TOGGLE

Master Slave Flip Flop With Preset And Clear –

Truth Table-

PRESET CLEAR CLK J K Q
0 0 x x x *
0 1 x x x 1
1 0 x x x 0
1 1 x 0 0 NC
1 1 up to down 0 1 0
1 1 up to down 1 0 1
1 1 up to down 1 1 Toggle

 

What is the Op Amp ?

54 thoughts on “What is Flip flop ?

  1. I manage a vape shop website directory and we have had a listing from a vape shop in the USA that likewise offers CBD goods. A Calendar month afterwards, PayPal has contacted use to say that our account has been limited and have requested us to take out PayPal as a payment solution from our vape store website directory. We do not retail CBD items like CBD oil. We simply offer web marketing professional services to CBD firms. I have checked out Holland & Barrett– the UK’s Top Health and wellness Merchant and if you take a close look, you will witness that they offer a relatively substantial series of CBD products, primarily CBD oil and they also happen to accept PayPal as a payment solution. It emerges that PayPal is administering double standards to different firms. Due to this stipulation, I can no longer accept PayPal on my CBD-related website. This has restrained my payment choices and right now, I am greatly contingent on Cryptocurrency payments and straightforward bank transfers. I have consulted with a lawyer from a Magic Circle law practice in London and they stated that what PayPal is doing is definitely against the law and discriminatory as it should be applying a systematic criterion to all companies. I am yet to check with another attorney from a US law office in London to see what PayPal’s legal position is in the USA. Meanwhile, I would be highly appreciative if anyone here at targetdomain could provide me with substitute payment processors/merchants that work with CBD firms.

  2. Does anyone know what happened to Dime Piece LA celebrity streetwear brand? I am unable to check out on Dimepiecela site. I have read in Harpers Bazaar that they were acquired by a UK hedge fund in excess of $50 million. I’ve just bought the Dimepiece Do You Faux Suede Square Pillow from Ebay and absolutely love it xox

  3. I oversee a vape shop web directory and we have had a listing from a vape shop in the USA that additionally advertises CBD goods. A Calendar month later, PayPal has written to use to say that our account has been limited and have requested us to take out PayPal as a payment solution from our vape shop directory. We do not offer for sale CBD goods such as CBD oil. We solely offer web marketing services to CBD firms. I have had a look at Holland & Barrett– the UK’s Major Wellness Store and if you take a good look, you will see that they offer a comparatively substantial variety of CBD product lines, primarily CBD oil and they also happen to take PayPal as a payment solution. It emerges that PayPal is applying double standards to many different companies. As a result of this stipulation, I can no longer take PayPal on my CBD-related online site. This has restrained my payment possibilities and now, I am seriously reliant on Cryptocurrency payments and direct bank transfers. I have consulted with a lawyer from a Magic Circle law practice in London and they explained that what PayPal is doing is absolutely against the law and inequitable as it should be applying a consistent benchmark to all firms. I am yet to check with a different lawyer from a US law firm in The city of london to see what PayPal’s legal position is in the USA. In the meantime, I would be highly appreciative if anybody here at targetdomain could offer me with alternative payment processors/merchants that work with CBD companies.

  4. Does anybody know if I am able to buy Just Delta 8 Gummies (justdeltastore.com) at Local Vape Shop, 1525 Mesa Verde Dr E #114, Costa Mesa, CA, 92626?

  5. It’s really very complex in this full of activity life to listen news on TV,
    thus I just use the web for that reason, and get the most recent news.

  6. Hmm is anyone else experiencing problems with the images on this blog loading?
    I’m trying to determine if its a problem on my
    end or if it’s the blog. Any suggestions would be greatly appreciated.

  7. By way of introduction, I am Mark Schaefer, and I represent Nutritional Products International. We serve both international and domestic manufacturers who are seeking to gain more distribution within the United States. Your brand recently caught my attention, so I am contacting you today to discuss the possibility of expanding your national distribution reach.We provide expertise in all areas of distribution, and our offerings include the following: Turnkey/One-stop solution, Active accounts with major U.S. distributors and retailers, Our executive team held executive positions with Walmart and Amazon, Our proven sales force has public relations, branding, and marketing all under one roof, We focus on both new and existing product lines, Warehousing and logistics. Our company has a proven history of initiating accounts and placing orders with major distribution outlets. Our history allows us to have intimate and unique relationships with key buyers across the United States, thus giving your brand a fast track to market in a professional manner. Please contact me directly so that we can discuss your brand further. Kind Regards, Mark Schaefer, marks@nutricompany.com, VP of Business Development, Nutritional Products International, 101 Plaza Real S, Ste #224, Boca Raton, FL 33432, Office: 561-544-0719

  8. I was wondering if anyone knows what happened to Dime Piece LA celebrity streetwear brand? I am having trouble to check out on Dimepiecela site. I’ve read in Cosmopolitan that the brand was bought out by a UK hedge fund for $50 m. I have just bought the Dimepiece Sport Heavyblend Crewneck Sweatshirt from Amazon and totally love it xox

  9. Does anyone know what happened to Dimepiece LA celebrity streetwear brand? I cannot check out on Dimepiecela site. I’ve read in GQ that the brand was acquired by a UK hedge fund for $50 m. I’ve just bought the Dimepiece International Playa Duffel from Amazon and totally love it xox

  10. Awsome article and straight to the point. I don’t know if this is truly the best place to ask but do you guys have any ideea where to employ some professional writers? Thanks 🙂

  11. What抯 Happening i am new to this, I stumbled upon this I’ve found It absolutely useful and it has aided me out loads. I hope to contribute & assist other users like its helped me. Good job.

  12. Hey are using WordPress for your site platform? I’m new to the blog world but I’m trying to get started and set up my own. Do you require any coding knowledge to make your own blog? Any help would be really appreciated!

  13. Hmm it looks like your website ate my first comment (it was super long) so I guess I’ll just sum it up what I wrote and say, I’m thoroughly enjoying your blog. I too am an aspiring blog writer but I’m still new to everything. Do you have any points for first-time blog writers? I’d definitely appreciate it.

  14. Thanks for your exciting article. One other problem is that mesothelioma cancer is generally a result of the breathing of fibres from mesothelioma, which is a dangerous material. It’s commonly found among staff in the structure industry with long contact with asbestos. It can be caused by moving into asbestos protected buildings for years of time, Your age plays an important role, and some folks are more vulnerable for the risk in comparison with others.

  15. One other issue is that if you are in a situation where you will not have a co-signer then you may really want to try to exhaust all of your educational funding options. You will find many awards and other free college funding that will offer you money to assist with university expenses. Thank you for the post.

  16. I do not even know how I ended up right here, however I assumed this submit was once great. I don’t recognize who you are however certainly you are going to a famous blogger for those who aren’t already 😉 Cheers!

  17. I oversee a vape store directory site and we have had a posting from a vape shop in the United States that also offers for sale CBD items. A Calendar month afterwards, PayPal has written to use to say that our account has been restricted and have requested us to get rid of PayPal as a payment solution from our vape store submission site. We do not sell CBD items like CBD oil. We only provide promotion and marketing professional services to CBD firms. I have checked out Holland & Barrett– the UK’s Top Wellness Retail store and if you take a good peek, you will witness that they sell a reasonably substantial variety of CBD items, primarily CBD oil and they also happen to take PayPal as a settlement method. It emerges that PayPal is administering contradictory standards to different firms. As a result of this restriction, I can no longer accept PayPal on my CBD-related website. This has limited my payment possibilities and currently, I am intensely contingent on Cryptocurrency payments and direct bank transfers. I have spoken to a lawyer from a Magic Circle law practice in London and they stated that what PayPal is doing is definitely unlawful and discriminatory as it ought to be applying a systematic benchmark to all firms. I am still to check with another lawyer from a US law practice in London to see what PayPal’s legal position is in the USA. In the meantime, I would be extremely appreciative if anyone here at targetdomain could offer me with substitute payment processors/merchants that work with CBD companies.

  18. I have come to understand that rates for internet degree authorities tend to be an excellent value. Like a full College Degree in Communication from The University of Phoenix Online consists of 60 credits from $515/credit or $30,900. Also American Intercontinental University Online comes with a Bachelors of Business Administration with a total course requirement of 180 units and a price of $30,560. Online studying has made getting your college degree far more easy because you may earn the degree from the comfort of your home and when you finish working. Thanks for all your other tips I have certainly learned through your web site.

  19. Thanks for your write-up. One other thing is that if you are disposing your property on your own, one of the issues you need to be aware of upfront is when to deal with property inspection reports. As a FSBO seller, the key about successfully transferring your property as well as saving money with real estate agent commissions is understanding. The more you understand, the smoother your home sales effort is going to be. One area that this is particularly critical is assessments.

  20. I have seen that good real estate agents almost everywhere are getting set to FSBO Advertising and marketing. They are noticing that it’s in addition to placing a sign in the front area. It’s really about building human relationships with these vendors who at some time will become purchasers. So, after you give your time and effort to serving these retailers go it alone : the “Law involving Reciprocity” kicks in. Good blog post.

  21. My brother suggested I might like this web site. He was totally right. This post truly made my day. You can not imagine just how a lot time I had spent for this information! Thanks!

  22. Thank you for all of your hard work on this web site. My niece really loves carrying out investigation and it’s really simple to grasp why. I know all about the lively way you give good tricks by means of your web site and as well as strongly encourage participation from some others on this theme then our princess is truly starting to learn a lot of things. Have fun with the rest of the new year. Your conducting a useful job.

  23. I think other website proprietors should take this web site as an model, very clean and excellent user genial style and design, let alone the content. You’re an expert in this topic!

  24. One thing is one of the most typical incentives for applying your credit cards is a cash-back and also rebate provision. Generally, you get 1-5 back in various expenses. Depending on the card, you may get 1 again on most purchases, and 5 again on expenditures made using convenience stores, filling stations, grocery stores plus ‘member merchants’.

  25. I enjoy you because of all your efforts on this web site. My mum really loves setting aside time for research and it is easy to understand why. My spouse and i notice all relating to the powerful ways you create reliable tips and hints by means of the blog and even attract contribution from some others on this situation and my girl is studying a great deal. Take pleasure in the rest of the year. Your carrying out a really great job.

  26. Thank you for the auspicious writeup. It if truth be told used to be a enjoyment account it. Look advanced to more introduced agreeable from you! By the way, how can we communicate?

  27. One thing I’d like to say is that often before buying more computer system memory, take a look at the machine within which it will be installed. If your machine will be running Windows XP, for instance, the memory ceiling is 3.25GB. Adding over this would basically constitute just a waste. Make sure that one’s mother board can handle your upgrade quantity, as well. Good blog post.

  28. Hi there! This post couldn’t be written any better! Reading through this post reminds me of my previous room mate! He always kept talking about this. I will forward this article to him. Pretty sure he will have a good read. Thank you for sharing!

Leave a Reply

Your email address will not be published. Required fields are marked *

error: Content is protected !!
Exit mobile version