Questions tagged [flipflop]
a flip-flop or latch is a circuit that has two stable states and can be used to store state information.
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How to build a selector
So I've been looking at this problem for a couple of hours, and I'm pretty sure I need to use finite state machines or at least some kind of memory elements to solve it... it goes as follows:
"A ...
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What exactly is a register?
Sometimes I'll look at registers in asm or when debugging a C output. What exactly is a register? In my understanding, it seems like it would consist of, for example 16 D-type flip-flops connected to ...
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One-way JK flip-flop using 74xx109
I want to design a flip flop circuit that effectively has one input and one output, as well as a reset trigger, along with clock and power, using a 74ACT109 JK flip flop. Basically, the output and ...
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What accounts for the current vacillation in this JK latch?
After trying a few different simulators (many of which didn't work for this) I was finally able to model a JK latch with NOR gates. Here is an example:
A weird thing seems to happen though (at least ...
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What's causing a master-slave JK flip flop to get 'stuck'?
I've built a JK master-slave flip flop according to the following schematic:
Putting it into Logicly I have the following diagram:
However, regardless of which switches I change, the final two NOR ...
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How to design a JK latch
I am trying to simulate a JK latch in a circuit builder. What I have come up with thus far is the following:
I don't have control of the wiring (the application automatically does these wirings, ...
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Master-slave flip flop without gate delay?
It seems like a master-slave flipflop always has around a 2-gate delay between the Master and Slave sections of the flip flop. For example:
My question is what would happen if, theoretically, there ...
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44 views
Can you have different clocks working at different intervals to operate a flip flop?
Is it possible to have two clock signals driving a JK toggling flip flop, in which both signals are connected by a XOr gate so that the flip flop only works on either edge of either clock? If possible,...
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Clearing 4-bit asynchronus counter using T flip-flops doesn't work
I am trying to make a BCD ripple counter that count from 0 to 9 , and I have watched a tutorial on YouTube , I implemented BCD counter as the instructor explained and after the counter reaches the ...
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For SR timing diagrams, does a bubble on the output of Q' indicate that it is the same as Q?
I understand that with flip flops when there is a bubble on the clock it means the clock cycle is in terms of the falling edge, but when there is a bubble on the output Q' isn't this inverting Q twice,...
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LED Circuit turns on or off after pulse of varying intensity
I'm trying to make a circuit that turns a LED on or off by using a pulse voltage. The LED should turn on with a pulse of intensity A and off with a pulse of B, where A and B < 5V. Most of the time, ...
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Doubt regarding static timing analysis - setup time check
I was reading J.Bhasker's STATIC TIMING ANALYSIS book. In that book, he tells that when launch flip flop launches the data & while capture flip flop is capturing data, he says that
We now ...
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Devices storing volatile memory
I've hit a bit of a rut in a question on my homework for my computer architecture class (MIPS architecture):
what are digital logic devices that can implement 1 bit and 32 bit volatile memory, and ...
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how to count like this: 0,1,2,1,2.. with 2bits register
Im trying to think about correct hardware design using verilog syntax to make a switch that counts like this:
if reset -> switch=0.
else
if (not reset) & (flag) -> switch=1, switch=2, switch=1, ...
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D type flip flop without clock
Is it possible to make a D type flip flop without a clock input? How would one set the logic to 0 or 1 without using a clock input?
Thank you.
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Requesting help with a circuit design
I am looking to build a float sensor for a tank and automating the motor based on sensor input. I am looking to execute this without using a microcontroller.
Below is my intended sensor setup in the ...
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How to Output DDR data to 1 register
I have an Input which provides DDR data, I need to capture it and output it from the FPGA in one register (12bit).
How can I do it?
What I did for now is to capture the input data with always block ...
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Interaction of D-Type flip-flops with SR inputs
I've recently been testing myself on D-Type FlipFlop interactions for an upcoming test. In the picture below, I've assumed that Clock overrides reset in the resulting output, Q:
Am I correct in this ...
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Modification to the D flip-flop
When we take a clock and a signal, the D flip flop output always gives "clock edge" AND, and the state will be high unto to the next clock cycle.
Now I want my output like like a latch, but timing ...
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1answer
108 views
Is this a good design for a 0…7 counter?
My daughter's electronics teacher recommends to realize a counter from 0...7 as follows:
It shall give an output pulse (for a subsequent circuit) when the button is hit the 8-th time.
For me this ...
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SR Latch confused about possible Race condition [duplicate]
Totally new to electrical and got confused when reading about SR Latch
[
What I am not sure is when R=0 then 2nd input on nor gate comes from output of nor gate below where again only value provided ...
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Change one Flip Flop with another (Are there basic rules how to replace them?) and how many states does a Circuit with flip flops have?
Hello I am studying for my exams and came across this thoughts.
D Flip Flops all have 2 states yes? 0 or 1, so If I have a circuit with 2 Flip Flops it has 2^2 states, yes?
And If I want to replace ...
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Unpowered clock divider
I am not a professional in this area, so I hope I am asking questions correctly.
I have a 5V clock pulse with 50-200Hz (square wave) and would like to build a simple unpowered clock divider. Output ...
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Designing a counter up using JK flip flop (odd numbers)
I'm designing a simple JK flip flop counter up with this pattern: 0-1-3-5-7-9-0. I already a did a multisim and it works fine. But when I change the JK FF to real IC (7473), it won't work. What is ...
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CMOS Flip-Flop Design
I'm new in Transistor-Level Design and for that reason, I have practiced and learned from designs that I found on google. When I tried to design a mux from scratch without relying on the design of ...
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Control several binary outputs with raspberry pi, CD74HC273 D-type flip flops and 5v relays
I am using a system with a raspberry pi and multiple d-type flip flop (CD74HC273), its role is to be able to control several digital outputs with a web app.
I use 8 raspbery GPIO bits as data/input ...
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Why can we avoid race around condition in JK flip flop by setting the T/2 of clock < propagation delay of flip flop
As the title suggests, my question is that why we can avoid race around condition in JK flip flop by setting the T/2 (T is time period here) of clock < propagation delay of flip flop?
The lecturer ...
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48 views
Changing T flipflop to D
For a recent examn, i was asked to create a counter, that counted backwards from 15-1 then starting over from 15, in odd numbers. I did so with a T flipflop, and the following question was for me to ...
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What is this symbol used in this D flip flop circuit? [duplicate]
I'm studying some notes on latches and flip flops. After the introduction of the D flip flop, the notes go on to explain its function - how it works. However, the first circuit diagram contains this ...
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Help understanding SR Flip-Flop
The table in the bottom image is the solution for an exercise based on a NAND SR flip-flop.
"Complete the truth table for the SR flip-flop."
The "initially" row is given, and I was supposed to fill ...
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Is there an intuitive explanation of the classic edge-triggered flip flop circuit?
I figure there must be a way to understand it in terms of the three underlying latches somehow locking each other out, but I'm not getting it.
Is there a way to understand the edge-triggered flip ...
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Need help making a counter controlled by a button
I'm trying to simulate a binary counter that is supposed to be activated by a button B, then count until 40, reset and stop until B gets pushed again. If B is pushed while the counter is working it ...
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Turning off and Flickering of LEDs for some reason
I've been following Ben Eater's You Tube series on building an 8 bit computer. As I built and connected more modules to the same power source, the LEDs connected to the registers started to flicker ...
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Trying to understand the difference between a regular clocked flip flop and a falling edge triggered one
I tried simulating both:
Falling edge triggered one
Regular clocked JK flip flop
I think there is something wrong with them because when both inputs are high they look like they are having a ...
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1answer
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JK flip flop not toggling when both inputs are 1?
Instead of toggling, this circuit throws this error. What does this mean and how do I fix it?
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Why is the SR Flip flop edge enabled
I'm struggling to understand the diference between a Latch and a SR Flip Flop, I know that a latch is level activated, and the SR Flip Flop is edge activated but if the circuit is the same, why is the ...
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Where do flip flops “save” their state?
From what I could understand, the state of a flip flop is the current value it is holding on to, i.e., the value that was previously inputted and is now saved for future use. My question is, where ...
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How to determine if an edge-triggered flip-flop is positive going or negative going?
I have an SR flip-flop such as above, and I'm to determine whether it's positive-going or negative-going. How can I do that?
I understand that edge-triggered flip-flops' output only change upon edges ...
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Adapting the 74LS170 open-collector “register file” to active-high TTL input
This is a question related to swapping a 74LS170 4 x 4 register file chip for a 74LS173 single 4-bit register. In the other question I wonder if there are even simpler ways to Turn a positive clock ...
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Turn a positive clock edge into a negative pulse to make a 74LS170/670 register file synchronous
This is a follow-up o Why did they make the 74x170 (670) register file asychronous, no CLK input?.
I want to use that "register file" for my project, but I need to make it behave properly as a ...
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1answer
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How to wire up a street light to change lights in specific states (digital circuit)
This is the final project for the only electronics course in my career. I have never taken any other electronics course and I'm seriously at a lost here. I need to score 100 here to pass the course.
...
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1answer
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Problem with 74HC76, silly mistake or possible fake?
I am a hobbyist and have been buying a few cheap ICs on AliExpress to play around with at home. I know that there is some risk involved in buying these but I seem to have had mostly good luck so far. ...
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State Machine with D Flip Flops; how to deal with race conditions
Consider a state machine whose entire state is kept in a collection of edge-triggered D flip-flops. The outputs of these are fed into a combinatorial network which fully determines the next state, and ...
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What is edge trigerring and what's need for it?
I was reading flip-flops and the text-book said that we should edge trigger flip-flops.
I didn't get what is edge triggering and why it is needed. Can anyone explain me ?
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DRAM inspired edge-triggered D-type flip-flop
I was thinking about using DRAM cells as edge-triggered D-type flip-flop, I put the elements in falstad circuit simulator and it worked, but I am not sure on how would this translate to an actual ...
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Calculate the next state for flip flop sequential circuit
Based on my previous question, i managed to draw out the truth table
Inputs for flipflops sequential circruits
...
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1answer
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Inputs for flipflops sequential circruits
Not very sure if these inputs are correct before i draw my truth table.
Too many lines and i am confused.
JA = QB = KA = B
KA = B
DB = D'
TC = 0
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Clock frequency divider circuit (divide by 2) using D flip flop
I was trying to implement frequency divider by 2 using D flip flop with the logic connection of ~Q to D input. I provide 2x clock frequency of 50% Duty cycle in the hardware where D flip flop is made ...
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2answers
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Prevent long press in changing state on D Flip-Flop
I've made a circuit on Logisim that allows me to switch between three LEDs at the push of a button. Essentially allowing me to cycle between OFF, LED1, LED2 and LED3 repeatedly. I'm doing this using ...
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1answer
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4-bit memory serial to parallel memory register circuit question
I am building a 4-bit serial to parallel memory register and I feel like so far I have gotten things right, but I'm unsure of where to connect the CLR connections.
Could someone have a look at my ...
