modified 11 years ago

Sr flipflop

00:55:35

Pure TTL SR flipflop

published 11 years ago

hurz

11 years ago

Looks more like a D FF. Check also this circuit i made " D Latch 1bit Counter - hurra "

pradd

11 years ago

@hurz Depends on how you look at it. It is D FF if you consider the not gate as part of it and it is SR FF and if you consider that to be a part of SR's support circuit

Sine_eyed

11 years ago

Whatever you wanna call it, its working so I'll give ya that. No one would build this though- is sort of um, overkill.

pradd

11 years ago

Thanks, I actually thought of building a couple

Sine_eyed

11 years ago

Really? I dunno why you would- I can understand if this is the internals of some IC and you wanted to see if you could simulate it, lots of us have done that. I'm just saying that it doesn't take 9 or 10 transistors to make a SR Latch. I'm all for building real circuits so I say go for it if you got the extra BJTs layin around- but you really only need two..

pradd

11 years ago

Just for fun :-) You're right, I only need two for SR and three for D

pradd

11 years ago

The second thought - how do you arrange clock input with only two BJTs?

Sine_eyed

11 years ago

Here's a better question-- What do you need a clock for?..

pradd

11 years ago

Don't you need something to schedule state updates? Otherwise it would simply output its input, in which case using a wire is simpler and much cheaper.

Sine_eyed

11 years ago

Yes, I would think you're right- at least for (whichever) the implementation you have in mind. I only want to make a simple point that a 2x BJT SR setup works amazingly well for uses outside of a computer. I've built a few real ones, made them modular (easily transplanted from one test circuit to another) with the idea that they serve a particular function in DIY security systems. Using mechanical (or hard sensor) switches, they have not failed me. I did encounter problems with input from a (opamp) comparator though.. =^/

pradd

11 years ago

See your point. Yes, you're right. In my case the thing is going to interface a computer on one side and some other device on the other side so clock input is a necessity.

add comment in editor

EveryCircuit is an easy to use, highly interactive circuit simulator and schematic capture tool. Real-time circuit simulation, interactivity, and dynamic visualization make it a must have application for professionals and academia. EveryCircuit user community has collaboratively created the largest searchable library of circuit designs. EveryCircuit app runs online in popular browsers and on mobile phones and tablets, enabling you to capture design ideas and learn electronics on the go.