Data Sheet

20
www.epluse.com v1.3 / Modification rights reserved
HTE501
6.11 Read Identification (0x7029)
Each sensor device has a specific 8-byte identification
This Identification allows a factory backtracking of each device.
When the following command is issued, the I
2
C slave sends all 8 bytes consecutively, followed by a CRC8
checksum (see chapter 6.14).
Command CMD Hex Code
Read Identification 0x7029
I²C
Datenstruktur
7654321 76543210 76543210 7654321
S
W
0
A
0
A
0
A
0
S
R
1
A
0
76543210 76543210 76543210
A
0
A
0
A
0
76543210 76543210 76543210
A
0
A
0
A
0
76543210 76543210 76543210
A
0
A
0
N
1
P
!
R / W R / W
I2C ADDRESS
CMD MSB=0x70
NEXT2I2C ADDRESS
Byte 1
2
Byte 2 Byte 3
NEXT3
Byte 7
4
Byte 8 CRC8
16 BIT COMMAND
CMD LSB=0x29
Byte 4
3
Byte 5 Byte 6
NEXT4
ASTRID_I2C_Befehle_version2 - Kopie / 0x7029 20.09.2021 \ Haider A.
Figure 22: Read Identification
Example:
“1C4606026156553C” (Hexadecimal)
6.12 Constant Current Heater (0x306D, 0x3066)
The constant current heater serves various purposes:

Sensor function test, switching on of heater at constant environmental conditions and adapted time
constants for T and RH
• Temperature T rises
• Humidity RH falls
• Dew point TD stays constant

Faster removal of condensation on the sensor

Avoid condensation for faster response time at highest humidity
• Humidity sensor operation at a constant over-temperature of approx. 5° C
• Dew point temperature readout from heated humidity sensor
• The actual temperature is measured by a second unheated sensor.
• The actual humidity is calculated with the help of the dew point temperature of the heated humidity
sensor and the temperature of the second unheated sensor.
The advantage of the “constant current heater” is that the power introduced by the heater, and thus also
the overtemperature of the sensor, only changes linearly with the supply voltage.