Rev. 0.2 / 09 /2015
7
AN1111-2
2.1.2 Correlation between sensor capacity and period
•
Humidity Sensor HCT01 (approx.):
70 pF @ 0 % rH
-
95 pF @ 100 % rH
•
Period at RH_OUT:
70 pF
19.0 µs cycle duration
95 pF
25.4 µs cycle duration
Figure 3: The sensitivity is approx. 0,064 µs/% rH (with a rise of 0.25 pF/% rH)
Figure 4: Nominal characteristic of the measuring device with frequency output
Figure 5: Example of RH & T measuring device with HCT01 and frequency output
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cy
cl
e p
er
io
d
[µs
]
relative humidity [% rH]
Nominal characteristic @5,0 V