Si7005 2 DIGITAL I C HUMIDITY AND TEMPERATURE SENSOR Features 2 Relative Humidity Sensor I C host interface 4.5 % RH (maximum 080% RH) Integrated on-chip heater Temperature Sensor 4x4 mm QFN package 0.5 C accuracy (typical) Excellent long term stability 1 C accuracy (maximum 0 to 70 C) Factory calibrated 0 to 100% RH operating range Optional factory-installed 40 to +85 C (GM) or 0 to +70 C cover operating range (FM) Low-profile Wide operating voltage range Protection during reflow Ordering Information (2.1 to 3.6 V) Excludes liquids and See Ordering Guide. Low Power Consumption particulates 240 A during RH conversion (hydrophobic/oleophobic) Patent protected patents pending Applications Pin Assignments Industrial HVAC/R Micro-environments/data centers Thermostats/humidistats Automotive climate control and de-fogging Respiratory therapy Asset and goods tracking White goods 1 18 DNC GND 2 17 DNC DNC Description 3 16 DNC SCL The Si7005 is a digital relative humidity and temperature sensor. This 4 15 CS SDA monolithic CMOS IC integrates temperature and humidity sensor 5 14 DNC DNC elements, an analog-to-digital converter, signal processing, calibration 6 13 DNC DNC 2 data, and an I C host interface. The patented use of industry-standard, low-K polymeric dielectrics for sensing humidity enables the construction of a low-power, monolithic CMOS sensor IC with low drift and hysteresis and excellent long term stability. Both the temperature and humidity sensors are factory-calibrated and the calibration data is stored in the on-chip non-volatile memory. This ensures that the sensors are fully interchangeable, with no recalibration or software changes required. The Si7005 is packaged in a 4x4mm QFN package and is reflow solderable. The optional factory-installed protective cover offers a low- profile, convenient means of protecting the sensor during assembly (e.g., reflow soldering) and throughout the life of the product, excluding liquids (hydrophobic/oleophobic) and particulates. The Si7005 offers an accurate, low-power, factory-calibrated digital solution ideal for measuring temperature, humidity, and dew-point in applications ranging from HVAC/R and asset tracking to industrial and consumer platforms. Rev. 1.2 1/14 Copyright 2014 by Silicon Laboratories Si7005 DNC 7 24 DNC GND 8 23 DNC VDD 9 22 DNC CEXT 10 21 DNC GND 11 20 DNC DNC 12 19 GNDSi7005 Functional Block Diagram V DD V DD NV CAL VDD 32 kHz Osc Humidity Sensor CEXT SCL 2 PXx I C Logic MUX ADC SDA PXy Serial IF CS PXz Temperature Sensor GND Microcontroller Si7005 2 Rev. 1.2 C = 0.1 F C = 4.7 F R = 10 k (typ) R = 10 k (typ) 2 I C pullups may be integrated in microcontroller