1. Home
  2. Hobby Electronics Basics
  3. 555/556 Timer Circuit

555/556 Timer Circuit

I'm kind of new to this electronics stuff. I took a class years ago and have a pretty good idea of how basic circuits work. I don't have a clue about IC's.

I am working on a little project which I don't know how to set up. I am using a 4.5VDC battery power source with a mercury switch that will be used to close the circuit and sound a buzzer. What is happening is that when the circuit closes the mercury will continue to slosh around and sound the buzzer multiple times. What I would like to happen is when the circuit closes it sounds the buzzer for a split second, opens and stays open for a determined amount of time (3sec) even if the mercury closes the circuit again. I was told I could use a 555 or 556 timer to accomplish that. I purchased both timers and set up a couple basic circuits that I saw on the internet. I've played around with the timers for a long time but I just can't figure out how to use them to accomplish my above goal.

I would surely appreciate any information or what I would need to purchase to get my circuit working. If you have any questions I would be happy to answer them. You can reach me by e-mail snipped-for-privacy@cox.net or phone 480-763-8199.

Thanks for Your Time,

Dave Kofka

Reply to
DaveK
Loading thread data ...

Dave,

It would help if you could provide a link to the circuit you're using, or post the schematic in alt.binaries.schematics.electronic . It should be easy figure out why it's not working.

The basic idea would be to use the first 555 to immediately fire and drive the buzzer. This first 555's output would also fire the second 555. The first 555 would timeout quickly and stop the buzzer. The second timer would have a longer delay (3 seconds) and would inhibit refiring of the first 555 until the 3 seconds elapsed.

There may be a tricky way to do it with a single 555 but using two (or a

556) would be easier.

Bob

Reply to
Bob 

--
View in Courier:
                                        CR1 
.                  +------------------[
Reply to
John Fields

On Sat, 10 Feb 2007 12:52:29 -0600, John Fields wrote:

--- I left out a couple of diodes.

Here's the LTSPICE circuit list:

Version 4 SHEET 1 1972 1056 WIRE 96 16 -448 16 WIRE 208 16 160 16 WIRE 240 16 208 16 WIRE 416 16 320 16 WIRE -672 80 -832 80 WIRE -560 80 -672 80 WIRE 16 80 -560 80 WIRE 288 80 16 80 WIRE 416 80 416 16 WIRE 416 80 288 80 WIRE 736 80 416 80 WIRE -672 112 -672 80 WIRE -560 112 -560 80 WIRE 288 128 288 80 WIRE -272 160 -336 160 WIRE 16 160 16 80 WIRE 16 160 -48 160 WIRE 112 160 16 160 WIRE 448 160 384 160 WIRE 736 160 736 80 WIRE 736 160 672 160 WIRE 832 160 736 160 WIRE 112 192 112 160 WIRE 832 192 832 160 WIRE -672 224 -672 176 WIRE -560 224 -560 192 WIRE -560 224 -672 224 WIRE -368 224 -560 224 WIRE -272 224 -368 224 WIRE 16 224 -48 224 WIRE 208 224 208 16 WIRE 288 224 288 192 WIRE 288 224 208 224 WIRE 448 224 288 224 WIRE 736 224 672 224 WIRE -672 256 -672 224 WIRE -448 288 -448 16 WIRE -272 288 -448 288 WIRE 16 288 16 224 WIRE 16 288 -48 288 WIRE 448 288 272 288 WIRE 736 288 736 224 WIRE 736 288 672 288 WIRE 16 320 16 288 WIRE 112 320 112 272 WIRE 112 320 16 320 WIRE 736 320 736 288 WIRE 832 320 832 272 WIRE 832 320 736 320 WIRE -832 352 -832 80 WIRE -304 352 -832 352 WIRE -272 352 -304 352 WIRE 112 352 112 320 WIRE 448 352 416 352 WIRE 832 352 832 320 WIRE -832 432 -832 352 WIRE -672 432 -672 320 WIRE -448 432 -448 288 WIRE -304 432 -304 352 WIRE 416 432 416 352 WIRE 416 432 -304 432 WIRE -368 496 -368 224 WIRE -112 496 -368 496 WIRE 272 496 272 288 WIRE 272 496 -48 496 WIRE -832 544 -832 512 WIRE -672 544 -672 512 WIRE -672 544 -832 544 WIRE -448 544 -448 512 WIRE -448 544 -672 544 WIRE -336 544 -336 160 WIRE -336 544 -448 544 WIRE 112 544 112 416 WIRE 112 544 -336 544 WIRE 384 544 384 160 WIRE 384 544 112 544 WIRE 832 544 832 416 WIRE 832 544 384 544 WIRE -832 592 -832 544 FLAG -832 592 0 SYMBOL Misc\\\\NE555 -160 256 R0 SYMATTR InstName U1 SYMBOL voltage -672 416 R0 WINDOW 3 24 104 Invisible 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR Value PULSE(4.5 0 .1 1e-6 1e-6 .01 .05) SYMATTR InstName V1 SYMBOL voltage -832 416 R0 WINDOW 123 0 0 Left 0 WINDOW 3 24 104 Invisible 0 SYMATTR Value 4.5 SYMATTR SpiceLine Rser=0 SYMATTR InstName V2 SYMBOL res 96 176 R0 SYMATTR InstName R2 SYMATTR Value 1e6 SYMBOL cap 96 352 R0 SYMATTR InstName C1 SYMATTR Value .5e-6 SYMBOL Misc\\\\NE555 560 256 R0 SYMATTR InstName U2 SYMBOL res 816 176 R0 SYMATTR InstName R4 SYMATTR Value 1e6 SYMBOL cap 816 352 R0 SYMATTR InstName C2 SYMATTR Value 5e-6 SYMBOL res 336 0 R90 WINDOW 0 -33 60 VBottom 0 WINDOW 3 -27 58 VTop 0 SYMATTR InstName R5 SYMATTR Value 10k SYMBOL cap 96 32 R270 WINDOW 0 69 32 VTop 0 WINDOW 3 66 35 VBottom 0 SYMATTR InstName C3 SYMATTR Value .1e-6 SYMBOL cap -656 320 R180 WINDOW 0 24 64 Left 0 WINDOW 3 24 8 Left 0 SYMATTR InstName C6 SYMATTR Value .1e-6 SYMBOL res -576 96 R0 SYMATTR InstName R6 SYMATTR Value 10k SYMBOL res -464 416 R0 SYMATTR InstName R1 SYMATTR Value 100 SYMBOL diode -48 480 R90 WINDOW 0 0 32 VBottom 0 WINDOW 3 32 32 VTop 0 SYMATTR InstName D1 SYMATTR Value 1N4148 SYMBOL diode -656 176 R180 WINDOW 0 46 30 Left 0 WINDOW 3 24 0 Left 0 SYMATTR InstName D2 SYMATTR Value 1N4148 SYMBOL diode 304 192 R180 WINDOW 0 -41 35 Left 0 WINDOW 3 -73 0 Left 0 SYMATTR InstName D3 SYMATTR Value 1N4148 TEXT -808 568 Left 0 !.tran 0 10s 0

-- JF

Reply to
John Fields

"DaveK" wrote in news:1171086622.883485.104430 @l53g2000cwa.googlegroups.com:

a

will

around

opens

the

See these delay circuits at :

formatting link

Reply to
roma

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.