Need help with a small project to measure the humidity

[rda]

Re: humidity sensor

Hi friends,
i have to do a small project to measure the humidity. using the HS1101 which have this characteristics at 1% ===>C=177pf
99%====>C=183pf

my question is how to transform the variation of the capacitance to variation of tension.

sorry for my english.

Added after 10 minutes:

i try this short simulation with isis pro and i obtain this.
1- astable which generate the rectangular signal.
2-monostable to modulate the width of the impulsion.
3-low pass filter to extract the DC tension.
for C=177pf ==>V=2.17 volts
and C=183pf==>V=2.2 volts

the variation is too short!!! how can i increase it

 

[GSM Man]

humidity sensor

I think you are misreading the datasheet. The spec showing 177pF to 183pF is the minimum & maximum capacitance at 55% RH, not the range from 0% to 100%. The capacitance is about 162pF at 0% RH and 201pF at 100% RH.

 

[rda]

Re: humidity sensor

thank you GSM Man, my english is so basic and didn't read the datasheet carefully

I finally got this results with (160pf to 210pf).