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It's simple. believe! the incubator is a box which a 220V AC light bulb is embedded in as a heater and a thermostat controls it.no additional device or accuracy is needed!
the temperature should be in 36-37 degree
Hi,
you just need some positive feedback (hysteresis).
See it as a "2 resistor voltage divider".
R1 from LM35 pin2 to OPAMP pin3
R2 from OPAMP pin1 to OPAMP pin3
Maybe make R1 = 100 R
Then calculate R2 to cause a (relative) voltage equal to 1°C at OPAMP pin3 with taking opamp_output_swing into account.
Klaus
added: I see there are no supply voltage stabilizing capacitors. --> Use a big bulk capacitor and a fast ceramics capacitor (this one close to the OPAMP supply pins)
bimetallic clock-spring and a mercury bulb switch
worked for many decades. But that's too simple
and reliable.
But that's too simple and reliable.
Hi,
did you use an internet search or a forum search?
--> "power supply bulk capacitor calculation" (electrolytic)
--> "power supply decoupling capacitors" (ceramics, often used: 100nF X7R at each supply pin of each IC)
Klaus
Why vague? It's just mathematics. All input values should be known or (in doubt) measurable.but finding the true values of R1&R2 are still a bit vague to me.
finding the true values of R1&R2 are still a bit vague to me.
. but finding the true values of R1&R2 are still a bit vague to me....
(Usually it´s me asking for requirements ;-) )In my personal opinion, you are starting at the wrong point. First you need to state your requirements.
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