SNAS758A February   2025  – June 2025 HDC3120

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Device Comparison
  6. Pin Configuration and Functions
  7. Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  8. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Device Power-Up
      2. 7.3.2 Device Disable and Enable
      3. 7.3.3 Conversion of the Signal Output
        1. 7.3.3.1 Relative Humidity (RH%) Measurement
        2. 7.3.3.2 Temperature Measurement
      4. 7.3.4 NIST Traceability and Unique ID
      5. 7.3.5 Output Short Circuit Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 On-Chip Heater
        1. 7.4.1.1 Operating Principle
          1. 7.4.1.1.1 Heater Configuration Example
        2. 7.4.1.2 Heater Electrical Behavior
        3. 7.4.1.3 Heater Temperature Increase
        4. 7.4.1.4 Heater Usage Guidelines
  9. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
    3. 8.3 Power Supply Recommendations
    4. 8.4 Rehydration Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
    6. 8.6 Storage and PCB Assembly
      1. 8.6.1 Storage and Handling
      2. 8.6.2 Product Storage
      3. 8.6.3 PCB Assembly Flow
      4. 8.6.4 Rework Consideration
      5. 8.6.5 Sensitivity to Chemicals and Vapors
      6. 8.6.6 Exposure to High Temperature and High Humidity Conditions
      7. 8.6.7 Recovering Sensor Performance: Bake and Rehydration Procedure
  10. Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Electrical Characteristics

TA = -40°C to 125°C, VDD = 1.62V to 5.5V, OUTRL = 50kΩ (unless otherwise noted); Typical specifications are at TA = 25°C and VDD = 3.3V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Relative Humidity Sensor
RHRANGE RH Operating Range 0 100 %RH
RHACC RH Accuracy(1)(2) TA = 25°C; 10% to 70% RH ±1.0 ±2.5 %RH
RHREP RH Repeatability TA = 25°C; 10% to 90% RH. Integrated over 1 second at constant TA ±0.02 %RH
RHHYS RH Hysteresis(3) ±0.8 %RH
τ63RH RH Response Time(4) τ = 63% for step response from 10% to 90% RH, TA = 25°C(6) 4 s
RHLTD RH Long-term Drift (5) ±0.19 %RH/yr
LSBRH RH Resolution (1 LSB) 12-bit DAC output 0.0244 %RH
tON-RH RH DAC Turn-On Time 17 ms
RHSENS RH Sensor Gain/ Sensitivity VDD = 1.8V 14.4 mV/%RH
VDD = 2.5V 20
VDD = 3.3V 26.4
VDD = 5V 40
RHOFFSET RH Sensor Offset Voltage 0.1×VDD V
Temperature Sensor
TEMPRANGE Temperature Operating Range –40 125 °C
TEMPACC Temperature Accuracy –10°C ≤ TA ≤ 60°C, VDD ≥ 2.5V ±0.1 ±0.3 °C
–10°C ≤ TA ≤ 90°C, VDD ≥ 2.5V ±0.15 ±0.4
–40°C ≤ TA ≤ 125°C, VDD ≥ 2.5V ±0.2 ±0.6
–20°C ≤ TA ≤ 85°C, VDD = 1.62V to 5.5V ±0.2 ±0.6
–40°C ≤ TA < 125°C, VDD = 1.62V to 5.5V ±0.3 ±0.8
TEMPREP Temperature Repeatability ±0.04 °C
TEMPHYS Temperature Hysteresis ±0.02 °C
τ63TEMP Temperature Response Time (25 °C to 75 °C)(4)(7) Stirred Oil. Single layer Flex PCB 0.13mm thickness 0.61 s
Stirred Oil. Single layer FR4 PCB 1.575mm thickness 1.78 s
Still Air. Single layer Flex PCB 0.13mm thickness 12.91 s
TEMPLTD Temperature Long Term Drift ±0.03 °C/yr
LSBTEMP Temperature Resolution (1 LSB) 12-bit DAC output 0.0427 °C
tON-TEMP TEMP DAC Turn-On Time 11 ms
TEMPSENS Temperature Sensor Gain/ Sensitivity VDD = 1.8V 8.2 mV/°C
VDD = 2.5V 11.4
VDD = 3.3V 15.1
VDD = 5V 22.9
TEMPOFFSET Temperature Sensor Offset Voltage 0.306×VDD V
Power Supply
IDD Average Supply Current (RESET_EN = High) RH, TEMP loading = 1 MΩ, TA = 25°C 250 370 µA
RH, TEMP loading = 1 MΩ 480 µA
VPOR Power-on Reset Threshold Voltage Supply voltage rising 1.35 1.45 V
VBOR Brownout Detect Threshold Voltage Supply voltage falling 1.1 1.25 V
Enable and Reset
IDD_DISABLE Average Supply Current - Disable Mode (RESET_EN = 0V) VDD = 1.62V 32 47 µA
VDD = 3.3V 64 95
VDD = 5.5V 106 160
VOUT_DISABLE TEMP and RH Pin Output Voltage in Disable Mode RESET_EN = 0V 0.3 10 mV
tRESET_EN Minimum Duration of Reset Pulse 1 µs
RRESET_EN RESET_EN pin Internal Pull-up Resistance 51
tON RESET_EN Turn-On Time Delay RESET_EN > VIH to valid RH output 8 ms
RESET_EN > VIH to valid Temp output 13 ms
tOFF RESET_EN Turn-Off Time Delay 0.45 ms
Analog Output
VO Output Voltage Range 0.1×VDD 0.9×VDD V
VOUT0 Power Up Default Output Prior to first measurement 0.1×VDD V
CL Capacitive Load Drive Strength No isolation resistor. Adequate phase margin with 45° or better  47 nF
RL Resistive Load Drive Strength 50 kΩ
ISC Short Circuit Current -16 ±7 16 mA
tSTL Settling Time Step Size = VDD/2. Settle to within ±0.5LSB. CLOAD = 1nF 0.5 ms
tCONV ADC RH+Temp Conversion Time 13 ms
tPERIOD ADC Sampling Period 250 ms
On-Chip Heater
R25-HEAT Heater Resistance 168.4
IHEAT Heater Current VDD = 1.8V 10 mA
VDD = 3.3V 19
VDD = 5V 28
PHEAT Heater Power VDD = 1.8V 18 mW
VDD = 3.3V 62
VDD = 5V 138
tON-HEAT Heater Turn-On Time Delay 130 ms
tOFF-HEAT Heater Turn-Off Time Delay 0.45 ms
Logic Input
VIH High Level Input Voltage RESET_EN, HEAT_EN Pins 0.7×VDD V
VIL Low Level Input Voltage 0.3×VDD V
Excludes hysteresis, long-term drift, and impact from device self-heating
Refer to RH Accuracy vs. RH Set Point plot for the rest of the RH% range
The hysteresis value is half of the largest difference between the RH measurement in a rising and falling RH environment. The value is measured between 10% and 90% RH range with a step size of 10%
Actual response times varies dependent on system thermal mass and air-flow
Based on THB (temperature humidity bias) testing using Arrhenius-Peck acceleration model. Excludes the impact of dust, gas phase solvents and other contaminants such as vapors from packaging materials, adhesives, or tapes, and more
Time for the RH output to change by 63% of the total RH change after a step change in environmental humidity
Time for the TEMP output to change by 63% of the total TEMP change after a step change in environmental temperature