hygrometer


Posted on Feb 6, 2014

What you have sounds like something from this type family of sensors. Not really a good choice of sensor for use with a PIC and actually a pretty low end sensor as to accuracy. There is a little more information located here. Personally I don`t see it as a good choice as there are many good temperature compensated 3 wire devices out there that are


hygrometer
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inexpensive. Anyway, the links may help. This is a capacitive type sensor and needs to be part of a circuit. Like an RC circuit. You thern need a table to determine the values outputted. I use the HIH-5031 sensor. Bit more expensive but work straight on ADC. Actually capacitive humidity sensors works pretty good if you couple it with a 555 timer in monostable mode. then you`d get a humidity versus frequency output. An output of 50Hz-2kHz is pretty easy to achieve, and it is trivial for a PIC in Timer0/Timer1 mode to read such frequencies. I`ve used Honeywell`s, they work good. I intended to have four separate inputs using this schematic. But this component will obviously not work. Anyone got anything that is suitable for the above I intended to have four separate inputs using this schematic. But this component will obviously not work. Anyone got anything that is suitable for the above You may want to give this link a read as to the HIH 4000 series of Honeywell sensors available from Mouser here. The HIH-4000-003 or HIH-4000-004 would do what you seem to be looking for. You don`t mention a desired accuracy




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