designing freezer alarm help

I am designing a freezer alarm for a project and have to research various circuits already being used. If anybody has any circuit diagrams or links to websites could they please post.

Google responds with 678,000 hits on "freezer alarm circuit". Designaing is not the same as making a copy.

danwilson6 said:

I am designing a freezer alarm for a project and have to research various circuits already being used. If anybody has any circuit diagrams or links to websites could they please post.

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If you really wish to solicit ideas and feedback you will probably have to show a little more effort on your part.

What are your specifications for the device, what is the target cost per unit, how large a production run is anticipated, what features does the device need to include, what will be the power source, etc, etc, etc ???

There is lots of knowledge and experience on this forum but it's not like they are very bored and just waiting for assignments

Lefty

Again the help from a comparator will do.The trick is with the thermistor's resistor.You need to know what resistance does it have in 0'C.

Then same as normal comparator circuit. You must place a reference point,if it exceed the voltage at reference output must be high or low.

what exactly you mean by a freezer alarm. there is a fridge door alarm which tells you if the fridge door has accidentally been left open.

sorry i wasn't more specific, i am designing the circuit uising the multisim programme. I will probably use the comparator circuit, i was wondering if anybody had any copies of any ideas. The circuit is to alert the consumer when the freezer temperature has increased to a certain temperature. I will only be designing the circuit there will be no manufacturing as it is a computer circuit design project, any information will be great thank you