Does anyone know of a small IC package for a "momentary latch"?

Thread Starter

durable126

Joined Feb 20, 2016
56
Let me just clarify

I want a pushbutton switch to latch on and off with a single press

The schematic In the link i posted above are all the same. The only difference is, when gives a high the other gives a low.

http://www.edn.com/design/power-management/4427218/Latching-power-switch-uses-momentary-pushbutton

Here is my version in the sim. Push the switch and you get no nothing





I have also tried another design from a guy in australia

His came from a youtube video.
Also does not work


 

dl324

Joined Mar 30, 2015
16,846
I wouldn't count on Multisim being able to simulate that circuit. In my experience, it doesn't do anything resembling analog.

Are you set on using discrete components? I have a circuit that was published in Popular Electronics 4 decades ago (IIRC) that uses 3 CMOS inverters; 2 for a latch and one to buffer the output of the latch..
 

Thread Starter

durable126

Joined Feb 20, 2016
56
I wouldn't count on Multisim being able to simulate that circuit. In my experience, it doesn't do anything resembling analog.

Are you set on using discrete components? I have a circuit that was published in Popular Electronics 4 decades ago (IIRC) that uses 3 CMOS inverters; 2 for a latch and one to buffer the output of the latch..
Hi there

Im set on simple is what I'm set on :) This thing has to go on a PCB and also have as low power consumption in the off state as possible.

I have had very good luck with multi sim doing pretty much everything i have ever asked it to from designing diff amps to 3 phase circuits. It does have some quarks but is about 500 times easier to use then orcad and i can get a student license for $40 that includes the ultiboard software for building the pcb. It can't get to much better for a student

With all that said, I'm very interested to hear what you got up your sleeve :)

I do have one design working with a D flip flop
 

Lindembruck

Joined Feb 28, 2016
46
That is a simple latch, and what you want is a toggle. In terms of circuit reliability, I think your best solution is to let the logic be logic and the power switch be a power switch: the single latch chip from above driving a small P-channel power MOSFET.

ak
Sim, ou talvez ainda um IGBT.
 

BillB3857

Joined Feb 28, 2009
2,570
Buttons work well, but are dull. No fun at all. What is really confusing is that a button must be used to start the electronic version.
 
Top