Once designed, plan for 1000 pieces...Hi, Thanks for responding. Its a diy project. The cost will determine the quantity. I was thinking a small watch type battery that would fit in the pen size cylinder. 1.5vdc I guess. A regular led should be good. The flash rate won't really matter. Is the microcontroller and power all this needs? What would the part cost about?
He wanted the LED to stay on for the first 60 seconds and then start flashing.I think two AAAA alkaline cells will fit in a pen. The LED can be a 1.8V flashing red LED plus a resistor to limit its current. Then no circuit is needed.
I found a 3.2V AAA size lithium cell but it is too fat to fit inside a pen.
It's trivial to do regardless, an LED, a tiny PIC (they do six pin SM ones), one resistor (to limit the current to the LED) and the battery - plus a little simple software.The 60 seconds staying on then flashing will be a lot more complicated and more expensive that just flashing all the time it is on. Also when the LED stays on then the battery life will be much shorter.
See post #4 above. I quoted the price of a PIC10-series. Price depends on quantity but about $0.35 to 0.45 each plus other listed parts (again, post 4).The circuit using a PIC 10F sounds great. Would this fit into a small cylinder? The cylinder could be a little larger than a pen. What all components are needed and what's the cost?
90 degrees what? Please note that this is an international forum so, since temperature is measured with different scales in different parts of the world, you need to specify which scale you're using.What I'm looking for is a simple circuit to light a led after a 60 second delay. Ideally it would start via a thermal sensor at about 90 degrees. This is for a cooking device, and no it's not for drugs. It could shut off when removed from the heat source or a switch.