Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [latch]

A latch or flip-flop is a circuit that has two stable states and can be used to store state information. However latch is normally used to describe a simple storage device while flip-flop is normally reserved for clocked devices.

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JK latch, possible Ben Eater error?

Is it possible that the schematic shown here is wrong? I would expect something more like that... It seems like that he inverted the feedback wires, but I'm quite suspicious because he made the circuit and it works, I'm a bit confused. EDIT: as…
Paa
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Doubt regarding SR latch

I am having trouble visualizing an SR latch intuitively. Here the two outputs \$Q, Q'\$ both are dependent on each other,so how will the two function at the same time? Let me break it down. Suppose I am just creating the circuit. I take one line of…
green_blue
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Why are two transmission used gates to make a D Latch?

In the circuit given below I can't understand what the second transmission gate TG2 is used for. It is connected both to the exit of a Transmission gate and an inverter... so what is the actual input and output of this circuit?
user165500
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Metastable state when S = R = 1 in SR Latch?

According to wikibooks, under the section SR Latch, S = R = 1 is a metastable state. The following things are mentioned under the heading When both inputs are high at once, however, there is a problem: it is being told to simultaneously produce a…
Murtaza Raja
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What is the meaning of a "soft" latch?

Googling for "soft latch" brings up many results, and on this site 12 out of 232 questions tagged latch contain the phrase "soft latch". However, there seem to be no references to a "hard latch" other than relating to breastfeeding and doors. What…
user218354
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SR latch with both inputs at 0

I know questions on SR latch and FF has come up fairly often and I've already seen answers that made me understand better how this device work. However, I still have a doubt when both input S and R are 0: from the thruth table it is known that the…
aghin00
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SR latch effect which only requires one GPIO

I have an STM6821TWY6F watchdog IC for my MCU. When the MCU gracefully goes to sleep it will disable the a watchdog to prevent unwanted wake ups. The watchdog was designed to look for an oscillating signal from the MCU that it can't and shouldn't…
Feynman137
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What is the name of the electrical latch with one toggle input?

For example pressing a momentary push button to toggle an led off and on through a Flip-Flop. I’ve only seen the ones where there are two buttons and you press both to switch the states. However I know one exists where you only have to push one…
Space-Rover
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Circuit to randomly light one LED or another

I am attempting to make a cheap and simple "quantum-ish" coin flip circuit. My idea is to use something like an SR latch driving two LEDs, and have the initialization be driven by some random event. I will be cross-posting in the physics stack…
Will Stedden
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Starting a latch in a known state

I have a latch, and I could use some advice on starting the latch in a known state. I'm running some robotics off of an ATX power supply, controlled by an Arduino. The motors and such are weak and not particularly dangerous, but just the same I'd…
Ed Krohne
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Help building a latch from 1 AND gate and 1 OR gate

I'm having trouble with part of a build I have to do for an alarm system circuit. The Boolean code is I = M.(A + B + C + D + E). The +s are ORs, . is AND, and I'm using 2-input OR gates and 2-input AND gates. When M, the master switch, is on, and…
somers
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How to convert SR (NOR) latch into S'R' (NAND) latch

What is the general rule of thumb to convert SR (NOR) latch into S'R' (NAND) latch? I only know the two inputs (S,R) need to be inverted. What about outputs (Q)?
VvOoGame
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Triggering an SR Latch with multiple reset lines

Ok, so I'm relatively new to electrical engineering having worked on the software side of life in the past. I'm trying to work a simple SR Latch where only one output is enabled at once. To do this, I've tried resetting the whole latch with each…
AQMS
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Input / output behaviour of dynamic latch

I'm studying this dynamic latch and I wonder why, when the switch closes the second time, in doesn't go up to high as well. When I consider only the switch and out, then everything makes sense. At least, when I ignore the inverse function of the…
Ben
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SR latch conventions

consider this rule: In SR latches using NOR gates the S should be connected to Q and the R should be connected to Q' and for the SR latches using NAND gates vice versa. is this a convention ? or a rule? and another question I have about conventions…
someone
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