User manual

OPERATION MANUAL
Technical changes reserved
0141 0316-119 17.08.2015
HYTEMOD-I2C-HUMIDITY MODULE WITH
VOLTAGE OUTPUT AND I²C-BUS
Standard model
The module is with 6-pole connector. The models available from
stock are congured as follows:
• Operating voltage range 6 … 12 V / 3 mA
• Calibrated at 8.0 V
• I
2
C Interface for temperature and humidity
• Ratiometric voltage output at PIN 6
0 ... 5 V corresponds to 0 ... 100% RH
• Temperature measurement by integrated Pt1000
• Module in plastic housing with connection cable and RJ12 plug
connector.
Voltage output
At PIN6, the measured relative humidity values are passed on as
voltage signal. The presented measuring range of 0 ... 5 V corres-
ponds to 0 ... 100% rH.
The minimum connection impedance should not be below 10 kOhm.
The output impedance is 50 Ohm. The output is protected against
short time transients. External voltage at the output can cause a
damage of the ASIC and is absolutely to be avoided.
Operating voltage
Standard system is with 6 to 12 V operating voltage which ist stabi-
lized in the module on 5 V. The 5 V operating voltage serves also as
reference level for the digital I2C-communication.
For the minimization of the self-heating over 8 V operating voltage,
we recommend the stainless steel housing.
I
2
C-Interface
The communication is as per I
2
C protocol. All technical specications
of the protocol and commands can be obtained from the documen-
tation “Serial Interface of HYGROSENS ASIC“. The documentation is
available on request.
The default address of the component is 0x78 and the component
can always be communicated at this address. In addition, a second
address can also be programmed during conguration at works,
under which the humidity probe can be addressed.
Up to 4 bytes can be read at the address 0x78. If temperature values
are not required, it is enough to read only the rst two bytes. The
following allocation is adopted:
Data
0x78 Byte_0 MSB Humidity
Byte_1 LSB Humidity
Byte_2 MSB Temperature
Byte_3 LSB Temperature
Scaling the measured values
Both humidity and temperature values are converted as 15 Bit values
(Bit 0 - 14). From the 15 bit measured values, 11 bit resolution is to be
used so that lower side bit (0 - 3) can be ignored.
The high value bit (15) is always 0 under normal operation and in
case of an error it is turned to 1. Further instructions on error codes
are available in the write-up “Serial Interface of HYGROSENS ASIC”.
For the readings following scaling is valid:
Humidity channel
Numerical value over
I
2
C Interface
0x 0000 ... 7FFF
dec. 0 ... 32767 (I2C)
Physical value 0 ... 100% RH
Scaling RH(I2C) [%]=I2C/327,68
Temperature channel
Numerical value over
I
2
C Interface
0x 0000 ... 7FFF
dec. 0 ... 32767(I2C)
Physical value -20 ... 60 °C
Scaling T(I2C) [°C]=I2C/409,59-20
Connector conguration
RJ 45 Colour Function
1 black VDD Supply Voltage 6...12 V
2 brown GND Ground
3 red SDA Serial Data I2C
4 orange SCL Serial Clock I2C
5 yellow URH RH Voltage Output
6 green --- Not used
top view
front
from the side
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