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Interfacing humidity sensor RHK1AN

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ex4

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rhk1an

Could anyone tell me how to interfacing humidity sensor RHK1AN, so the output is a dc voltage from 0 - 5VDC. the spec is:
- resistive sensor
- 1Vpp AC source
and anybody got the datasheet???mine is partial, not complete..... :(
 

IanP

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datasheet rhk1an

It looks like this sensor can be used in a ac-bridge configuration with a sine-wave generator of 1Vrms to supply this bridge. To measure its ac-resistance you will need AC-DC active converter, microcontroller with internal/external A/D converter etc.
Now, there is a catch: this sensor is also temperature dependant so you will need to read temperature and calibrate this sensor with at least 2 temperature values (assuming soensor's characteristic against temperature is linear).

The last will be D/A converter with 0-5V range.
 

IanP

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sensor rhk1an

Here you can find application note on the RHK1AN humidity sensor:

**broken link removed**
 

ex4

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0-5v humidity sensor

well,i got that file already
but wuihhhh it complex :(
can anybody suggest any simple one?
 

IanP

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interfacing humidity sensor to microcontroller

If you don't care about temperature, to provide 0-5V output you will need only the following blocks:
1) Sinewave generator ( 2 op-anps)
2) Bridge with amplifier (1 op-amp)
3)AC to DC coverter (2 op-amps)
This sensor requires certain conditions and if you not fulfil them there is no point of using it..
Otherwise, select different sensor, such as from Philips or Honeywell..
 

Fragrance

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how to calibrate humidity sensor

ex4 said:
Could anyone tell me how to interfacing humidity sensor RHK1AN, so the output is a dc voltage from 0 - 5VDC. the spec is:
- resistive sensor
- 1Vpp AC source
and anybody got the datasheet???mine is partial, not complete..... :(

Try this just two IC used virtual groud as shown in power jpg

note that the voltage are ac volt peak to peak adjusted never try to check sensor with OHM meter or applying dc volt it will distory sensor polymer coating. ploymer caoting energize with ac volt
 

ex4

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philips datasheet sensor umidity

i'll try that, wait for the development
:) :)
 

ex4

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greeting...
i have managed to interfacing RHK1AN using only one op amp LM324, but i'm now confused on how to calibrate it??? :(
got any suggestion??
my teacher told to make an inkubator with a hygrometer and compare it with my tranducers, and make the look up table?? how about that???
 

aink

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Dear Fragrance...

I had downloaded your picture about humidity sensor, but i have some problem now.
I just don't understand about the Power Supply circuit.
Where's the input and where's the output?
Please explain it to me?

Thank's
 

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