How can I design a 30-second lag time timer using a 555 timer?

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big_tobacco
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Hello,

Please could you help me with this problem;

I need to design a timer whereby I briefly trigger it (using a push to make/push to break switch connected to a 6 v supply), there is a pause of 30 seconds and then it triggers with an output, say an LED - this stayes on for about 10 seconds then automatically extinguishes, after it has extinguished it then shuts off. It's only until I trigger the PTM/PTB switch again that the sequence begins all over.

Please, please help...I was hoping to possibly use a 555 timer(s) or something very simple.

Hope you can help :cry:

Regards
 
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Push to make/push to break? I assume you mean a single pole single throw momentary switch?
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If so, I would use 555 timers, or a single 556. Configure them monostable. Make one time out at 30 seconds, the other at 40 seconds. Hook the LED between the outputs, or buffered outputs.
 
Welcome to PF big_tobacco. I agree with Averagesupernova in using a couple of 555s or a 556 to generate your pulses but if you have any kind of large load to consider, you might want to use a
http://www.factorymation.com/s.nl;jsessionid=0a010c491f434401fa96817849d4a900c5c8249efc4a.e3eSc3aPaxmLe34Pa38Ta38NaNb0?sc=2&category=100" .
 
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Maybe something from the Microchip http://www.microchip.com/ParamChartSearch/chart.aspx?branchID=1009&mid=10&lang=en&pageId=74" families?

The ATMEL equivalent is the http://www.atmel.com/dyn/products/devices.asp?family_id=607#791" family.

They *are* simple--it's just that it's simple software instead of simple hardware.

EDIT: But yeah, if you have any kind of large load, go with the time-delay relay as dlgoff recommends. On the other hand, depending on what sort of expertise you have, you *could* drive a triac or relay.
 
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Brilliant, thank you very much for your help. I think this weekend I'll crack out the bread-board and give these a try!