SI7021S

Part 1: Markdown Summary

Part: Si7021

Type: I2C Humidity and Temperature Sensor

Key Specs:

• Relative Humidity Sensor Accuracy: ± 3% RH (max), 0–80% RH
• Temperature Sensor Accuracy: ±0.4 °C (max), –10 to 85 °C
• Operating RH Range: 0 to 100% RH
• Operating Temperature Range: –40 to +125 °C
• Operating Voltage: 1.9 to 3.6 V
• Active Current: 150 μA
• Standby Current: 60 nA

Features:

• Precision Relative Humidity Sensor
• High Accuracy Temperature Sensor
• Factory-calibrated
• I2C Interface
• Integrated on-chip heater
• 3x3 mm DFN Package
• Excellent long term stability
• Optional factory-installed cover

Applications:

• HVAC/R
• Thermostats/humidistats
• Respiratory therapy
• White goods
• Indoor weather stations
• Micro-environments/data centers
• Automotive climate control and defogging
• Asset and goods tracking
• Mobile phones and tablets

Package:

• DFN Package: 3x3 mm

• Precision Relative Humidity Sensor

  • ± 3% RH (max), 0–80% RH

• High Accuracy Temperature Sensor

  • ±0.4 °C (max), –10 to 85 °C

• 0 to 100% RH operating range

• Up to –40 to +125 °C operating range

• Wide operating voltage (1.9 to 3.6 V)

• Low Power Consumption

  • 150 μA active current
  • 60 nA standby current

• Factory-calibrated

• I 2C Interface

• Integrated on-chip heater

• 3x3 mm DFN Package

• Excellent long term stability

• Optional factory-installed cover

  • Low-profile
  • Protection during reflow
  • Excludes liquids and particulates

• HVAC/R
• Thermostats/humidistats
• Respiratory therapy
• White goods
• Indoor weather stations
• Micro-environments/data centers
• Automotive climate control and defogging
• Asset and goods tracking
• Mobile phones and tablets

Unless otherwise specified, all min/max specifications apply over the recommended operating conditions.

Table 1. Recommended Operating Conditions

Table 2. General Specifications

1.9 ≤ VDD ≤ 3.6 V; TA = -40 to 85 °C (G grade) or -40 to 125 °C (I/Y grade); default conversion time unless otherwise noted.

Notes:

• Initiating a RH measurement will also automatically initiate a temperature measurement. The total conversion time will be t_CONV(RH) + t_CQNV(T).
• 2. No conversion or I²C transaction in progress. Typical values measured at 25 °C.
• 3. Occurs once during powerup. Duration is <5 msec.
• Occurs during I²C commands for Reset, Read/Write User Registers, Read EID, and Read Firmware Version. Duration is <100 μs when I²C clock speed is >100 kHz (>200 kHz for 2-byte commands).
• 5. IDD after a user register write. Initiating any other subsequent I²C transaction on the same bus (such as the user register read, starting an RH measurement, or traffic directed at other I²C devices) will transition the device to standby mode.
• 1. Additional current consumption when HTRE bit enabled. See section "5.5. Heater" for more information

Table 2. General Specifications (Continued)

1.9 ≤ VDD ≤ 3.6 V ; TA = -40 to 85 °C (G grade) or -40 to 125 °C (I/Y grade); default conversion time unless otherwise noted.

Notes:

• 1. Initiating a RH measurement will also automatically initiate a temperature measurement. The total conversion time will be t_CONV(RH) + t_CONV(T) .
• 1. No conversion or I²C transaction in progress. Typical values measured at 25 °C.
• 1. Occurs once during powerup. Duration is <5 msec.
• 4. Occurs during I²C commands for Reset, Read/Write User Registers, Read EID, and Read Firmware Version. Duration is <100 μs when I²C clock speed is >100 kHz (>200 kHz for 2-byte commands).
• 1. IDD after a user register write. Initiating any other subsequent I²C transaction on the same bus (such as the user register read, starting an RH measurement, or traffic directed at other I²C devices) will transition the device to standby mode.
• 1. Additional current consumption when HTRE bit enabled. See section "5.5. Heater" for more information

Notes:

• 1. Absolute maximum ratings are stress ratings only, operation at or beyond these conditions is not implied and may shorten the life of the device or alter its performance.
• 2. Special handling considerations apply; see application note, "AN607: Si70xx Humidity Sensor Designer's Guide".