Product specifications

AREXX Engineering & JM3 Engineering
Version: 1.05 Nov. 9
th
, 2014 page: 9
3.2. HTU21D
Read Commands
Hex Code
Comment
Trigger Temperature Measurement
0xE3
Hold master
Trigger Humidity Measurement
0xE5
Hold master
Trigger Temperature Measurement
0xF3
No Hold master
Trigger Humidity Measurement
0xF5
No Hold master
Write user register
0xE6
Read user register
0xE7
Soft Reset
0xFE
User Register
Bit
# Bits
default
Measurement Resolution
Bit 7 Bit 0 RH Temp
0 0 12 bits 14 bits
0 1 8 bits 12 bits
1 0 10 bits 13 bits
1 1 11 bits 11 bits
7,0
2
‘00’
Status End of Battery
‘0’: VDD>2.25V
‘1’: VDD<2.25V
6
1
‘0’
Reserved – do not modify
3,4,5
3
‘0’
Enable on-chip heater
2
1
‘0’
Disable OTP reload
1
1
For more details of the chip functionality please refer to the datasheet.
4. Technical Data
VDD = 3.3 V +/- 5%
IDD ≤ 1.5 mA (peak)
≤ 0.2 µA (standby)
Temperature Range: -10 to 65 °C
Key features:
 High resolution module
- Altitude: 20cm
- Humidity: 0,04%
 Fast conversion
 Integrated digital pressure sensor (24 bit ΔΣ ADC)
 Operating range: 10 to 1200 mbar
 Excellent long term stability
 Instantaneous desaturation after long periods in saturation phase
 Factory calibrated