SI7022-A20-YM0

Si 7 0 2 2 - A20 H U MI D I T Y / TEMPERATURE S ENSOR WITH P W M O UTPUT Features       Precision Relative Humidity Sensor  ± 4% RH (max), 0–80% RH High Accuracy Temperature Sensor ±0.4 °C (max), –10 to 85 °C 0 to 100% RH operating range –40 to +125 °C operating range Wide operating voltage (1.9 to 3.6 V) Low Power Consumption Factory-calibrated PWM Output  3x3 mm DFN Package  Excellent long term stability  Optional factory-installed cover Low-profile Protection during reflow Excludes liquids and particulates   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  Ordering Information: See page 18. Pin Assignments Description Top View The Si7022 Humidity and Temperature Sensor is a monolithic CMOS IC integrating humidity and temperature sensor elements, an analog-to-digital converter, signal processing, calibration data, and a PWM output. The PWM output may be filtered to produce an analog voltage output. The patented use of industry-standard, low-K polymeric dielectrics for sensing humidity enables the construction of low-power, monolithic CMOS Sensor ICs with low drift and hysteresis, and excellent long term stability. The humidity and temperature 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 Si7022 is available in a 3x3 mm DFN package and is reflow solderable. It can be used as a hardware- and software-compatible drop-in upgrade for existing RH/ temperature sensors in 3x3 mm DFN-6 packages, featuring precision sensing over a wider range and lower power consumption. The optional factory-installed 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. PWM1 1 6 SELECT GND 2 5 VDD DNC 3 4 PWM2 Patent Protected. Patents pending The Si7022 offers an accurate, low-power, factory-calibrated digital solution ideal for measuring humidity, dew-point, and temperature, in applications ranging from HVAC/R and asset tracking to industrial and consumer platforms. Rev. 1.3 8/16 Copyright © 2016 by Silicon Laboratories Si7022-A20 Si7022-A20 Functional Block Diagram Vdd Si7022 Humidity Sensor 1.25V Ref Calibration Memory Control Logic ADC SELECT Temp Sensor PWM Interface GND 2 Rev. 1.3 PWM1 PWM2 Si7022-A20 TABLE O F C ONTENTS Section Page 1. Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4 2. Typical Application Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 3. Bill of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4. Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 4.1. Relative Humidity Sensor Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 4.2. Hysteresis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 4.3. Prolonged Exposure to High Humidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 4.4. PCB Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 4.5. Protecting the Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.6. Bake/Hydrate Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.7. Long Term Drift/Aging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 5. PWM Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 6. Pin Descriptions: Si7022 (Top View) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 7. Ordering Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 8. Package Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 8.1. Package Outline: 3x3 6-pin DFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 8.2. Package Outline: 3x3 6-pin DFN with Protective Cover . . . . . . . . . . . . . . . . . . . . . . 20 9. PCB Land Pattern and Solder Mask Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 10. Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22 10.1. Si7022 Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 10.2. Top Marking Explanation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 11. Additional Reference Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Document Change List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24 Rev. 1.3 3 Si7022-A20 1. Electrical Specifications Unless otherwise specified, all min/max specifications apply over the recommended operating conditions. Table 1. Recommended Operating Conditions Symbol Parameter Power Supply Operating Temperature Test Condition Min Typ Max Unit VDD 1.9 — 3.6 V TA –40 — +125 °C Table 2. General Specifications 1.9 < VDD < 3.6 V; TA = –40 to 125 °C unless otherwise noted. Parameter Symbol Test Condition Min Typ Max Unit Input Voltage High VIH SELECT pin 0.7xVDD — — V Input Voltage Low VIL SELECT pin — — 0.3xVDD V Input Voltage Range VIN SELECT pin with respect to GND 0.0 — VDD V Input Leakage IIL SELECT pin — — 1 μA VOH PWM1, PWM2 pins, IOH = –10 μA VDD – 0.1 — — V PWM1, PWM2 pins pin, IOH = –0.5 mA, VDD = 2.0 V VDD – 0.2 — — PWM1, PWM2 pins, IOH = –1.7 mA, VDD = 3.0 V VDD – 0.4 — — PWM1, PWM2 pins; IOL = 2.5 mA; VDD = 3.3 V — — 0.6 V PWM1, PWM2 pins; IOL = 1.2 mA; VDD = 1.9 V — — 0.4 V RH and Temperature — 2 — Hz μA Output Voltage High Output Voltage Low VOL Sample Rate Current Consumption IDD Average Current — 150 300 Powerup Time tPU From VDD ≥ 1.9 V to PWM output enabled, 25 °C — 48 55 From VDD ≥ 1.9 V to PWM output enabled, full temperature range — — 110 4 Rev. 1.3 ms Si7022-A20 Table 3. PWM Interface Specifications 1.9  VDD  3.6 V; TA = –40 to +125 °C unless otherwise noted. Parameter Symbol Test Condition Min Typ Max Unit 1.00 1.22 1.40 kHz PWM Frequency FPWM PWM Duty Cycle DCPWM tH / tPWM 0 — 1 tSS From SELECT transition to PWM valid — 500 — SELECT Setup Time ms tPWM tH tSS RH Data Temperature Data Figure 1. PWM Interface Timing Diagram Rev. 1.3 5 Si7022-A20 Table 4. Humidity Sensor 1.9 ≤ VDD ≤ 3.6 V; TA = 30 °C Parameter Operating Accuracy Symbol Range1 2, 3 Test Condition Min Typ Max Unit Non-condensing 0 — 100 %RH 0 – 80% RH — ±3 ±4 %RH 80 – 100% RH See Figure 2. Repeatability/Noise — 0.025 — %RH RMS Resolution — 11 — Bits — 6 — S Drift vs. Temperature — 0.05 — %RH/°C Hysteresis — ±1 — %RH — < 0.25 — %RH/yr Response Time Long Term 4 τ63% 1 m/s airflow, with or without cover Stability3 Notes: 1. Recommended humidity operating range is 20% to 80% RH (non-condensing) over –10 °C to 60 °C. Prolonged operation beyond these ranges may result in a shift of sensor reading, with slow recovery time. 2. Excludes hysteresis, long term drift, and certain other factors and is applicable to non-condensing environments only. See Section “4.1. Relative Humidity Sensor Accuracy” for more details. 3. Drift due to aging effects at typical room conditions of 30 °C and 30% to 50% RH. May be impacted by dust, vaporized solvents or other contaminants, e.g., out-gassing tapes, adhesives, packaging materials, etc. See Section “4.7. Long Term Drift/Aging” . 4. Response time to a step change in RH. Time for the RH output to change by 63% of the total RH change. Figure 2. RH Accuracy at 30 °C 6 Rev. 1.3 Si7022-A20 Table 5. Temperature Sensor 1.9 ≤ VDD ≤ 3.6 V; TA = –40 to +125 °C unless otherwise noted. Parameter Symbol Test Condition Operating Range Accuracy Min Typ Max Unit –40 — +125 °C — ±0.3 ±0.4 °C –10 °C< tA < 85 °C –40 < tA < 125 °C Figure 3. Repeatability/Noise — 0.04 — °C RMS Resolution — 11 — Bits Unmounted device — 0.7 — s Si7022-EB board — 5.1 — —  0.01 — Response Time* τ63% Long Term Stability °C/Yr *Note: Time to reach 63% of final value in response to a step change in temperature. Actual response time will vary dependent on system thermal mass and air-flow. Figure 3. Temperature Accuracy Rev. 1.3 7 Si7022-A20 Table 6. Thermal Characteristics Parameter Symbol Test Condition DFN-6 Unit Junction to Air Thermal Resistance JA JEDEC 2-Layer board, No Airflow 256 °C/W Junction to Air Thermal Resistance JA JEDEC 2-Layer board, 1 m/s Airflow 224 °C/W Junction to Air Thermal Resistance JA JEDEC 2-Layer board, 2.5 m/s Airflow 205 °C/W Junction to Case Thermal Resistance JC JEDEC 2-Layer board 22 °C/W Junction to Board Thermal Resistance JB JEDEC 2-Layer board 134 °C/W Table 7. Absolute Maximum Ratings1 Parameter Min Typ Max Unit Ambient temperature under bias –55 — 125 °C Storage Temperature2 –65 — 150 °C Voltage on I/O pins –0.3 — VDD+0.3 V V Voltage on VDD with respect to GND –0.3 — 4.2 V HBM — — 2 kV CDM — — 1.25 kV MM — — 250 V ESD Tolerance Symbol Test Condition 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”. 8 Rev. 1.3 Si7022-A20 2. Typical Application Circuits The primary function of the Si7022 is to measure relative humidity and temperature. Figure 4 demonstrates the typical application circuit to achieve these functions. 1.9 V to 3.6 V C1 0.1 µF 5 SELECT 6 VDD Si7022 PWM1 R1 100 k  1 VRH/VTEMP C2 1 µF SELECT PWM2 4 VTEMP/VRH R2 100 k  GND 2 C3 1 µF Optional U1 Figure 4. Typical Application Circuit for Relative Humidity and Temperature Measurement Rev. 1.3 9 Si7022-A20 3. Bill of Materials Table 8. Typical Application Circuit BOM for Relative Humidity and Temperature Measurement Reference Description Mfr Part Number Manufacturer C1 Capacitor, 0.1 μF, 16 V, X7R, 0603 Various Various R1 Resistor, 100 k, ±5%, 1/16W, 0603 Various Various C2 Capacitor, 1 μF, 16 V, X7R, 0603 Various Various R2 Resistor, 100 k, ±5%, 1/16W, 0603 (optional) Various Various C3 Capacitor, 1 μF, 16 V, X7R, 0603 (optional) Various Various U1 IC, Digital Temp/Humidity Sensor Si7022-A20 Silicon Labs 10 Rev. 1.3 Si7022-A20 4. Functional Description Vdd Si7022 Humidity Sensor 1.25V Ref Calibration Memory Control Logic ADC SELECT Temp Sensor PWM Interface PWM1 PWM2 GND Figure 5. Si7022 Block Diagram The Si7022 is a digital relative humidity and temperature sensor that integrates temperature and humidity sensor elements, an analog-to-digital converter, signal processing, calibration, polynomial non-linearity correction, and a PWM output all in a single chip. The Si7022 is individually factory-calibrated for both temperature and humidity, with the calibration data stored in on-chip, non-volatile memory. This ensures that the sensor is fully interchangeable, with no recalibration or changes to software required. Patented use of industry-standard CMOS and low-K dielectrics as a sensor enables the Si7022 to achieve excellent long term stability and immunity to contaminants with low drift and hysteresis. The Si7022 offers a low-power, high-accuracy, calibrated and stable solution ideal for a wide range of temperature, humidity, and dew-point applications including medical and instrumentation, high-reliability automotive and industrial systems, and cost-sensitive consumer electronics. While the Si7022 is largely a conventional mixed-signal CMOS integrated circuit, relative humidity sensors in general and those based on capacitive sensing using polymeric dielectrics have unique application and use requirements that are not common to conventional (non-sensor) ICs. Chief among those are: The need to protect the sensor during board assembly, i.e., solder reflow, and the need to subsequently rehydrate the sensor. The need to protect the senor from damage or contamination during the product life-cycle. The impact of prolonged exposure to extremes of temperature and/or humidity and their potential effect on sensor accuracy. The effects of humidity sensor “memory”. Each of these items is discussed in more detail in the following sections. Rev. 1.3 11 Si7022-A20 4.1. Relative Humidity Sensor Accuracy To determine the accuracy of a relative humidity sensor, it is placed in a temperature and humidity controlled chamber. The temperature is set to a convenient fixed value (typically 25–30 °C) and the relative humidity is swept from 20 to 80% and back to 20% in the following steps: 20% – 40% – 60% – 80% – 80% – 60% – 40% – 20%. At each set-point, the chamber is allowed to settle for a period of 60 minutes before a reading is taken from the sensor. Prior to the sweep, the device is allowed to stabilize to 50%RH. The solid trace in Figure 6, “Measuring Sensor Accuracy Including Hysteresis,” shows the result of a typical sweep. Figure 6. Measuring Sensor Accuracy Including Hysteresis The RH accuracy is defined as the dotted line shown in Figure 6, which is the average of the two data points at each relative humidity set-point. In this case, the sensor shows an accuracy of 0.25%RH. The Si7022 accuracy specification (Table 4) includes: Unit-to-unit and lot-to-lot variation of factory calibration Margin for shifts that can occur during solder reflow The accuracy specification does not include: Accuracy Hysteresis (typically ±1%) from long term exposure to very humid conditions Contamination of the sensor by particulates, chemicals, etc. Other aging related shifts ("Long-term stability") Variations due to temperature (see Drift vs. Temperature in Table 4). RH readings will typically vary with temperature by less than  0.05%  C. Effects 12 Rev. 1.3 Si7022-A20 4.2. Hysteresis The moisture absorbent film (polymeric dielectric) of the humidity sensor will carry a memory of its exposure history, particularly its recent or extreme exposure history. A sensor exposed to relatively low humidity will carry a negative offset relative to the factory calibration, and a sensor exposed to relatively high humidity will carry a positive offset relative to the factory calibration. This factor causes a hysteresis effect illustrated by the solid trace in Figure 6. The hysteresis value is the difference in %RH between the maximum absolute error on the decreasing humidity ramp and the maximum absolute error on the increasing humidity ramp at a single relative humidity setpoint and is expressed as a bipolar quantity relative to the average error (dashed trace). In the example of Figure 6, the measurement uncertainty due to the hysteresis effect is ±1.0%RH. 4.3. Prolonged Exposure to High Humidity Prolonged exposure to high humidity will result in a gradual upward drift of the RH reading. The shift in sensor reading resulting from this drift will generally disappear slowly under normal ambient conditions. The amount of shift is proportional to the magnitude of relative humidity and the length of exposure. In the case of lengthy exposure to high humidity, some of the resulting shift may persist indefinitely under typical conditions. It is generally possible to substantially reverse this effect by baking the device (see Section “4.6. Bake/Hydrate Procedure” ). 4.4. PCB Assembly 4.4.1. Soldering Like most ICs, Si7022 devices are shipped from the factory vacuum-packed with an enclosed desiccant to avoid any RH accuracy drift during storage and to prevent any moisture-related issues during solder reflow. The following guidelines should be observed during PCB assembly: Si7022 devices are compatible with standard board assembly processes. Devices should be soldered using reflow per the recommended card reflow profile. See Section “9. PCB Land Pattern and Solder Mask Design” for the recommended card reflow profile. A "no clean" solder process is recommended to minimize the need for water or solvent rinses after soldering. Cleaning after soldering is possible, but must be done carefully to avoid impacting the performance of the sensor. See “AN607: Si70xx Humidity Sensor Designer’s Guide” for more information on cleaning. It is essential that the exposed polymer sensing film be kept clean and undamaged. This can be accomplished by careful handling and a clean, well-controlled assembly process. When in doubt or for extra protection, a heat-resistant, protective cover such as Kapton™ KPPD-1/8 polyimide tape can be installed during PCB assembly. Si7022s may be ordered with a factory-fitted, solder-resistant protective cover. This cover provides protection during PCB assembly or rework but without the time and effort required to install and remove the Kapton tape. It can be left in place for the lifetime of the product, preventing liquids, dust or other contaminants from coming into contact with the polymer sensor film. See Section “7. Ordering Guide” for a list of ordering part numbers that include the cover. Rev. 1.3 13 Si7022-A20 4.4.2. Rehydration The measured humidity value will generally shift slightly after solder reflow. A portion of this shift is permanent and is accounted for in the accuracy specifications in Table 4. After soldering, an Si7022 should be allowed to equilibrate under controlled RH conditions (room temperature, 45–55%RH) for at least 48 hours to eliminate the remainder of the shift and return the device to its specified accuracy performance. 4.4.3. Rework To maintain the specified sensor performance, care must be taken during rework to minimize the exposure of the device to excessive heat and to avoid damage/contamination or a shift in the sensor reading due to liquids, solder flux, etc. Manual touch-up using a soldering iron is permissible under the following guidelines: The exposed polymer sensing film must be kept clean and undamaged. A protective cover is recommended during any rework operation (Kapton® tape or the factory installed cover). Flux must not be allowed to contaminate the sensor; liquid flux is not recommended even with a cover in place. Conventional lead-free solder with rosin core is acceptable for touch-up as long as a cover is in place during the rework. If possible, avoid water or solvent rinses after touch-up. Cleaning after soldering is possible, but must be done carefully to avoid impacting the performance of the sensor. See “AN607: Si70xx Humidity Sensor Designer’s Guide” for more information on cleaning. Minimize the heating of the device. Soldering iron temperatures should not exceed 350 °C and the contact time per pin should not exceed five seconds. Hot air rework is not recommended. If a device must be replaced, remove the device by hot air and solder a new part in its place by reflow following the guidelines above. *Note: All trademarks are the property of their respective owners. Figure 7. Si7022 with Factory-Installed Protective Cover 14 Rev. 1.3 Si7022-A20 4.5. Protecting the Sensor Because the sensor operates on the principal of measuring a change in capacitance, any changes to the dielectric constant of the polymer film will be detected as a change in relative humidity. Therefore, it is important to minimize the probability of contaminants coming into contact with the sensor. Dust and other particles as well as liquids can affect the RH reading. It is recommended that a cover is employed in the end system that blocks contaminants but allows water vapor to pass through. Depending on the needs of the application, this can be as simple as plastic or metallic gauze for basic protection against particulates or something more sophisticated such as a hydrophobic membrane providing up to IP67 compliant protection. The Si7022 may be ordered with a factory-fitted, solder-resistant cover that can be left in place for the lifetime of the product. It is very low-profile, hydrophobic and oleophobic. See Section “7. Ordering Guide” for a list of ordering part numbers that include the cover. A dimensioned drawing of the IC with the cover is included in Section “8. Package Outline” . Other characteristics of the cover are listed in Table 9. Table 9. Specifications of Protective Cover Parameter Value Material PTFE Operating Temperature –40 to 125 °C Maximum Reflow Temperature IP Rating (per IEC 529) 260 °C IP67 4.6. Bake/Hydrate Procedure After exposure to extremes of temperature and/or humidity for prolonged periods, the polymer sensor film can become either very dry or very wet, in each case the result is either high or low relative humidity readings. Under normal operating conditions, the induced error will diminish over time. From a very dry condition, such as after shipment and soldering, the error will diminish over a few days at typical controlled ambient conditions, e.g., 48 hours of 45 ≤ %RH ≤ 55. However, from a very wet condition, recovery may take significantly longer. To accelerate recovery from a wet condition, a bake and hydrate cycle can be implemented. This operation consists of the following steps: Baking the sensor at 125 °C for ≥ 12 hours Hydration at 30 °C in 75% RH for ≥ 10 hours Following this cycle, the sensor will return to normal operation in typical ambient conditions after a few days. 4.7. Long Term Drift/Aging Over long periods of time, the sensor readings may drift due to aging of the device. Standard accelerated life testing of the Si7022 has resulted in the specifications for long-term drift shown in Table 4 and Table 5. This contribution to the overall sensor accuracy accounts only for the long-term aging of the device in an otherwise benign operating environment and does not include the effects of damage, contamination, or exposure to extreme environmental conditions. Rev. 1.3 15 Si7022-A20 5. PWM Output During operation, the Si7022 takes a relative humidity and temperature measurement once per second and converts the result into a pulse width modulated waveform. Two output pins are available for reading the measurement results: PWM1 and PWM2. The information output on each pin is determined by the SELECT pin as follows: Table 10. PWM Outputs Voltage on SELECT Pin PWM1 Output PWM2 Output High RH Temperature Low Temperature RH The duty cycle of the waveform on the PWM outputs corresponds to the relative humidity and temperature results shown in the following equations. The PWM duty cycle varies linearly with the measurement result between the minimum and maximum values: RH (%RH) = – 6 + 125  DC PWM Where DC PWM is the ratio of high time to period (i.e., a number that varies from 0 to 1) Equation 1. T(°C) = – 46.85 + 175.72  DC PWM Equation 2. In the typical application, the PWM output is filtered using an RC network to provide an analog output voltage that varies linearly with RH and temperature. See Section “2. Typical Application Circuits” for the recommended application circuit. Due to normal variations in RH accuracy of the device as described in Table 4, it is possible for the measured value of %RH to be slightly less than 0 when the actual RH level is close to or equal to 0. Similarly, the measured value of %RH may be slightly greater than 100 when the actual RH level is close to or equal to 100. This is expected behavior. 16 Rev. 1.3 Si7022-A20 6. Pin Descriptions: Si7022 (Top View) PWM1 1 6 SELECT GND 2 5 VDD DNC 3 4 PWM2 Pin Name Pin # Pin Description PWM1 1 Pulse width modulated output #1 GND 2 Ground. This pin is connected to ground on the circuit board through a trace. Do not connect directly to GND plane. DNC 3 This pin should be soldered to pads on the PCB for mechanical stability. It can be electrically floating or tied to VDD (do not tie to GND). PWM2 4 Pulse width modulated output #2 VDD 5 Power. This pin is connected to power on the circuit board. SELECT 6 Digital input that toggles between RH and temperature outputs on PWM1 and PWM2. This pin should be pulled high or low (do not leave floating). TGND Paddle This pad is connected to GND internally. This pad is the main thermal input to the onchip temperature sensor. The paddle should be soldered to a floating pad. Rev. 1.3 17 Si7022-A20 7. Ordering Guide Table 11. Device Ordering Guide P/N Description Max. Accuracy Temp Si7022-A20-IM Pkg Operating Range (°C) Protective Cover Packing Format RH Digital temperature/ humidity sensor – ±0.4 °C industrial temp range ± 4% DFN 6 –40 to +125 °C N Cut Tape Si7022-A20-IMR Digital temperature/ humidity sensor – industrial temp range ±0.4 °C ± 4% DFN 6 –40 to +125 °C N Tape & Reel Si7022-A20-IM1 Digital temperature/ humidity sensor – industrial temp range ±0.4 °C ± 4% DFN 6 –40 to +125 °C Y Cut Tape Si7022-A20-IM1R Digital temperature/ humidity sensor – industrial temp range ±0.4 °C ± 4% DFN 6 –40 to +125 °C Y Tape & Reel Si7022-A20-YM0 Digital temperature/ humidity sensor – automotive ±0.4 °C ± 4% DFN 6 –40 to +125 °C N Cut Tape Si7022-A20-YM0R Digital temperature/ humidity sensor – automotive ±0.4 °C ± 4% DFN 6 –40 to +125 °C N Tape & Reel Si7022-A20-YM1 Digital temperature/ humidity sensor – automotive ±0.4 °C ± 4% DFN 6 –40 to +125 °C Y Cut Tape Si7022-A20-YM1R Digital temperature/ humidity sensor – automotive ±0.4 °C ± 4% DFN 6 –40 to +125 °C Y Tape & Reel Note: The “A” denotes product revision A and “20” denotes firmware version 2.0. 18 Rev. 1.3 Si7022-A20 8. Package Outline 8.1. Package Outline: 3x3 6-pin DFN Figure 10. 3x3 6-pin DFN Table 12. 3x3 6-pin DFN Package Diagram Dimensions Dimension Min Nom Max A 0.70 0.75 0.80 A1 0.00 0.02 0.05 b 0.35 0.40 0.45 D D2 3.00 BSC. 1.40 1.50 e 1.00 BSC. E 3.00 BSC. 1.60 E2 2.30 2.40 2.50 H1 0.85 0.90 0.95 H2 1.39 1.44 1.49 L 0.35 0.40 0.45 aaa 0.10 bbb 0.10 ccc 0.05 ddd 0.10 eee 0.05 fff 0.05 Notes: 1. All dimensions shown are in millimeters (mm). 2. Dimensioning and Tolerancing per ANSI Y14.5M-1994. Rev. 1.3 19 Si7022-A20 8.2. Package Outline: 3x3 6-pin DFN with Protective Cover Figure 8 illustrates the package details for the Si7022 with the optional protective cover. Table 13 lists the values for the dimensions shown in the illustration. Figure 8. 3x3 6-pin DFN with Protective Cover Table 13. 3x3 6-pin DFN with Protective Cover Package Diagram Dimensions Dimension A A1 A2 b D D2 e E E2 F1 F2 h L R1 aaa bbb ccc ddd eee Min — 0.00 0.70 0.35 1.40 2.30 2.70 2.70 0.76 0.35 0.45 Nom — 0.02 0.75 0.40 3.00 BSC. 1.50 1.00 BSC. 3.00 BSC. 2.40 2.80 2.80 0.83 0.40 0.50 0.10 0.10 0.05 0.10 0.05 Max 1.21 0.05 0.80 0.45 1.60 2.50 2.90 2.90 0.90 0.45 0.55 Notes: 1. All dimensions are shown in millimeters (mm). 2. Dimensioning and Tolerancing per ANSI Y14.5M-1994. 20 Rev. 1.3 Si7022-A20 9. PCB Land Pattern and Solder Mask Design   Figure 9. Si7022 PCB Land Pattern Table 14. PCB Land Pattern Dimensions Symbol mm C1 2.90 E 1.00 P1 1.60 P2 2.50 X1 0.45 Y1 0.85 Notes: General 1. All dimensions shown are at Maximum Material Condition (MMC). Least Material Condition (LMC) is calculated based on a Fabrication Allowance of 0.05 mm. 2. This Land Pattern Design is based on the IPC-7351 guidelines. Solder Mask Design 3. All metal pads are to be non-solder mask defined (NSMD). Clearance between the solder mask and the metal pad is to be 60 µm minimum, all the way around the pad. Stencil Design 4. A stainless steel, laser-cut and electro-polished stencil with trapezoidal walls should be used to assure good solder paste release. 5. The stencil thickness should be 0.125 mm (5 mils). 6. The ratio of stencil aperture to land pad size should be 1:1 for all perimeter pins. 7. A 2x1 array of 1.00 mm square openings on 1.30 mm pitch should be used for the center ground pad to achieve a target solder coverage of 50%. Card Assembly 8. A No-Clean, Type-3 solder paste is recommended. 9. The recommended card reflow profile is per the JEDEC/IPC J-STD-020 specification for Small Body Components. Rev. 1.3 21 Si7022-A20 10. Top Marking 10.1. Si7022 Top Marking 10.2. Top Marking Explanation 22 Mark Method: Laser Font Size 0.30 mm Pin 1 Indicator: Circle = 0.30 mm Diameter Upper-Left Corner Line 1 Marking: TTTT = Mfg Code Rev. 1.3 Si7022-A20 11. Additional Reference Resources AN607: Si70xx Humidity Sensor Designer’s Guide Rev. 1.3 23 Si7022-A20 DOCUMENT CHANGE LIST Revision 0.9 to Revision 1.0   Updated Table 2. Updated Table 3. Revision 1.0 to Revision 1.1 Updated Section “4.5. Protecting the Sensor”  Updated Table 9  Updated Table 13 dimensions F1 and F2  Revision 1.1 to Revision 1.2  Updated PWM Duty Cycle parameter in Table 3 on page 5.  Updated Equation 1 and Equation 2 on page 16. Revision 1.2 to Revision 1.3  Changed packing format from tube to cut tape for all non-tape & reel part numbers without protective filter covers. 24 Rev. 1.3 Smart. Connected. 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