TH02 ETC2 | Alldatasheet

Document overview

  • Manufacturer or author: Provided By ALLDATASHEET.COM(FREE DATASHEET DOWNLOAD SITE)
  • PDF pages: 26

Technical content

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com - 1 - D IGIT A L I 2 C H UMIDITY AND TEMPERATURE S ENSOR Version No. Revisions Date V1.0 First released version 2013.05 V1.1 Modify the current part 2013.08

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com - 2 - D IGIT A L I 2 C H UMIDITY AND TEMPERATURE S ENSOR

Features

„ Relative Humidity Sensor „ I2C host interface z ± 4.5 % RH (maximum @ 20–80% RH) „ Integrated on-chip heater „ Temperature Sensor z ±0.5 ºC accuracy (typical) „ Excellent long term stability ±1 ºC accuracy (maximum @ 0 to 70 °C) 0 to 100% RH operating range „ –40 to +85 ºC (GM) or 0 to +70 ºC operating range (FM) „ Wide operating voltage range (2.1 to 3.6 V) „ Low Power Consumption z 240 µA during RH conversion

Applications

„ Factory calibrated „ Optional factory-installed cover z Low-profile z Protection during reflow z Excludes liquids and particulates (hydrophobic/oleophobic)

Ordering Information

See Ordering Guide. Patent protected; patents pending „ Industrial HVAC/R „ Thermostats/humidistats „ Respiratory therapy „ White goods

Description

„ Micro-environments/data centers „ Automotive climate control and de-fogging „ Asset and goods tracking The TH02 is a digital relative humidity and temperature sensor. This monolithic CMOS IC integrates temperature and humidity sensor elements, an analog-to-digital converter, signal processing, calibration data, and an I 2C 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. Pin Assignments

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com - 3 - TABLE OF C ONTENT S Section Page

  1. Electrical Specifications

Unless otherwise specified, all min/max specifications apply over the recommended operating conditions. Table 1. Recommended Operating Conditions Table 2. General Specifications 2.1 ≤ VDD ≤ 3.6 V; TA = 0 to 70 °C (F grade) or –40 to 85 °C (G grade) unless otherwise noted.

  1. SDA and SCL pins have an internal 75 kΩ pull-up resistor to VDD

Table 3. General Specifications (Continued) 2.1 ≤ VDD ≤ 3.6 V; TA = 0 to 70 °C (F grade) or –40 to 85 °C (G grade) unless otherwise noted.

  1. SDA and SCL pins have an internal 75 kΩ pull-up resistor to VDD

Table 4. I2C Interface Specifications* 2.1≤ VDD ≤ 3.6 V; TA = 0 to 70 °C (F grade) or –40 to +85 °C (G grade) unless otherwise noted. *Note: All values are referenced to VIL and/or VIH. Figure 1. I2C Interface Timing Diagram

Table 5. Humidity Sensor 2.1 ≤ VDD ≤ 3.6 V; TA = 25 °C; tCONV = 35 ms unless otherwise noted.

  1. Recommended humidity operating range is 20 to 80% RH (non-condensing) over 0 to 60 °C. Prolonged operation

beyond these ranges may result in a shift of sensor reading, with slow recovery time.

  1. The TH02 has a nominal output of 16 codes per %RH, with 0h0000 = –24%RH.
  2. Excludes hysteresis, long term drift, and certain other factors and is applicable to non-condensing environments only.

See section “4.2. Relative Humidity Sensor Accuracy” for more details.

  1. May be impacted by dust, vaporized solvents or other contaminants, e.g., out-gassing tapes, adhesives, packaging

materials, etc. See section “4.10. Long Term Drift/Aging”.

  1. Time for sensor output to reach 63% of its final value after a step change.

Table 6. Temperature Sensor 2.1 ≤ VDD ≤ 3.6 V; TA = 0 to 70 °C (F grade) or –40 to +85 °C (G grade); tCONV = 35 ms unless otherwise noted.

  1. The TH02 has a nominal output of 32 codes /°C, with 0000 = –50 °C
  2. Temperature sensor accuracy is for VDD = 2.3 to 3.6 V.
  3. Actual response times will vary dependent on system thermal mass and air-flow.

Table 7. Absolute Maximum Ratings1,2

  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.

  1. For best accuracy, after removal from the sealed shipping bags, the TH02 should be stored in climate controlled

small upwards shift in RH readings. recalibration or software changes required. Each of these items is discussed in more detail in the following sections.

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com - 10 - The RH accuracy is defined as the center (red) line shown in Figure 2, 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 TH02 accuracy specification includes: „ Unit-to-unit and lot-to-lot variation in non-linearity compensation „ Accuracy of factory calibration „ Margin for shifts that can occur during solder reflow (compensation for shift due to reflow is included in the linearization procedure below).The accuracy specification does not include: „ Hysteresis (typically ±1%) „ Effects 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. After application of temperature compensation, RH readings will typically vary by less than ±0.05%/°C.

The values for the correction coefficients are shown in Table 8. Table 8. Linearization Coefficients

the RH reading from the TH02 must be compensated for the change in temperature relative to 30 °C. „ RHTempCompensated is the temperature compensated relative humidity value in %RH. „ RHLinear is the linear corrected relative humidity value in %RH. „ Temperature is the ambient temperature in °C as measured by the TH02 on chip temperature sensor. coefficients are shown in Table 9. Table 9. Linearization Coefficients Figure 7. In the case of Figure 7, the measurement uncertainty due to the hysteresis effect is ±1.05%RH. possible to substantially reverse this affect by baking the device.

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com - 13 - 2.7. Soldering TH02 devices are shipped, like most ICs, vacuum-packed with an enclosed desiccant to avoid any drift during storage as well as to prevent any moisture-related issues during solder reflow. Devices should be soldered using reflow and a “no clean” solder process, as a water or so lvent rinse after soldering will affect accuracy. PCB Land Pattern and Solder Mask Design” for the recommended card reflow profile. The measured humidity value will generally shift slightly af ter solder reflow. This shift is accounted for when using the linearization procedure given above. After soldering, TH02 should be allowed to equilibrate under controlled RH conditions (room temperature, 45–55%RH) for at least 48 hours to reach rated accuracy. During soldering, it is recommended that a protective cover of some kind be in place. Kapton®* polyimide tape is recommended as a protective cover. Alternatively, TH02s may be ordered with a factory fitted, solder-resistant protective cover which 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. Ordering Guide” for a list of ordering part numbers that include the cover. Hot air rework is not recommended. Soldering iron touch up is possible if flux is not needed and care is taken to avoid excessive heating. If rework is required, remove the part by hot air and solder a new part by reflow. Use only no-clean solder. Do not use solder resin or post-solder solvent cleanse.

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com - 14 - 2.8. 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 filter 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. TH02s may be ordered with a factory fitted, solder-resistant cover, which can be left in place for the lifetime of the product. It is very low-profile, hydrophobic and oleophobic, and excludes particulates down to 0.35 microns in size. SOrdering 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. The sensor should be protected from direct sunlight to prevent heating effects as well as possible material degradation. 2.9. 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 fe w 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. 2.10. Long Term Drift/Aging Over long periods of time, the sensor readings may drif t due to aging of the device. Standard accelerated life testing of the TH02 has resulted in the specifications for long-term drift. 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 affects of damage, contamination, or exposure to extreme environmental conditions.

transfer rates up to 400 kHz. Table 24 shows the register summary of the TH02.

  1. Set START (D0) in CONFIG to begin a new conversion
  2. Poll RDY (D0) in STATUS (register 0) until it is low (= 0)
  3. Read the upper and lower bytes of the RH value from DATAh and DATAl (registers 0x01 and 0x02),

respectively. Table 10 shows the format of the 12-bit relative humidity result.

  1. Convert the RH value to %RH using the following equation:
  2. Apply temperature compensation and/or linearization as discussed elsewhere in this data sheet

Table 11 shows the 12-bit values that correspond to various measured RH levels. Table 10. 12-Bit Relative Humidity Result Available in Registers 1 and 2 Table 11. Typical %RH Measurement Codes for 0 to 100% RH Range

12 Bit Code %RH

  1. Set START (D0) and TEMP (D4) in CONFIG (register 0x03) to begin a new conversion, i.e., write CONFIG with
  2. Poll RDY (D0) in STATUS (register 0) until it is low (=0)
  3. Read the upper and lower bytes of the temperature value from DATAh and DATAl (registers 0x01 and 0x02),

where TEMP is the measured value returned in DATAh:DATAI. Table 13shows the 14-bit values that correspond to various measured temperature levels. Table 12. 14-Bit Temperature Result Available in Registers 1 and 2

Table 13. Typical Temperature Measurement Codes for the –40 °C to 100 °C Range

14 Bit Code Temp(°C)

resolution of the measurements. Table 14 is a comparison of the normal and fast modes. Table 14. Normal vs. Fast Mode measurement when the TH02 is used in conjunction with a separate temperature sensor such as another TH02. tendency of the humidity sensor to accumulate an offset due to "memory" of sustained high humidity conditions. When the heater is enabled, the reading of the on-chip temperature sensor will be affected (increased). for the various device revisions and may include revisions not yet in existence. Table 15. Revision Values

powered down when the master controller is communicating with the other slave devices. The format of the address byte is shown in Table 16. Table 16. I2C Slave Address Byte acknowledge the data byte, after which the master issues a Stop command (P). See Table 17. Table 17. I2C Write Sequence

followed by a stop command. (See Table 19). Table 18. I2C Read Sequence for a Single Register Table 19. I 2C Read Sequence for RH or Temperature Conversion Result

capacitance of the I2C bus lines and the desired speed of operation. GPIO is not capable of sourcing/sinking 40 mA, then the TH02 will take longer to powerup and powerdown. Figure 2. Recommended Connection Diagram for Low-Power Battery Operation

Table 20 contains a summary of the TH02 register set. Each register is described in more detail below. Table 20. TH02 Register Summary

0 STATUS RSVD RSVD RSVD RSVD RSVD RSVD RSVD /RDY

1 DATAh Relative Humidity or Temperature, High Byte

2 DATAl Relative Humidity or Temperature, Low Byte

3 CONFIG RSVD RSVD FAST TEMP RSVD RSVD HEAT START

17 ID ID3 ID2 ID1 ID0 0 0 0 0

  1. Any register address not listed here is reserved and must not be written.
  2. Reserved register bits (RSVD) must always be written as zero; the result of a read operation on these bits is

7:1 Reserved Reserved. Reads undefined. 0 = conversion complete; results available in DATAh:DATAl.

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com - 23 - Register 1. DATAh Bit D7 D6 D5 D4 D3 D2 D1 D0 Name Relative Humidity or Temperature, High Byte Type R Reset Settings = 0000_0000 Bit Name Function 7:0 DATAh Data, High Byte. Eight most significant bits of a temperature or humidity measurement. See Table 14 or Table 16 for the measurement format. Register 2. DATAI Bit D7 D6 D5 D4 D3 D2 D1 D0 Name Relative Humidity or Temperature, Low Byte Type Read Reset Settings = 0000_0000 Bit Name Function 7:0 DATAl Data, Low Byte. Eight least significant bits of a temperature or humidity measurement. See Table 14 or Table 16 for the measurement format.

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com - 24 - Register 3. CONFIG Bit D7 D6 D5 D4 D3 D2 D1 D0 Name FAST TEMP HEAT START Type R/W R/W R/W Reset Settings = 0000_0000 Bit Name Function 7:6 Reserved Reserved. Reads undefined. Always write as zero. 5 FAST Fast Mode Enable. 0 = 35ms (typical) 1 = 18ms (typical) 4 TEMP Temperature Enable. 0 = Relative humidity 1 = Temperature 3:2 Reserved Reserved. Reads undefined. Always write as zero. 1 HEAT Heater Enable. 0 = heater off 1 = heater on 0 START Conversion Start. 0 = do not start a conversion 1 = start a conversion Register 17. ID Bit D7 D6 D5 D4 D3 D2 D1 D0 Name ID7 ID6 ID5 ID4 ID3 ID2 ID1 ID0 Type R R R R R R R R Reset Settings = 0101_0000 Bit Name Function 7:0 ID Identification. See section “5.1.5. Device Identification”.

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com - 25 - . 6. Pin Descriptions: TH02 Mechanical Dimension (unit: mm) Notes： General tolerance ±0.1

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com - 26 - HOPE MICROELECTRONICS CO.,LTD Add: 2/F, Building 3, Pingshan Private Enterprise Science and Technology Park, Lishan Road, XiLi Town, Nanshan District, Shenzhen, Guangdong, China Tel: 86-755-82973805 Fax: 86-755-82973550 Email: sales@hoperf.com Website: http://www.hoperf.com http://www.hoperf.cn This document may contain preliminary information and is subject to change by Hope Microelectronics without notice. Hope Microelectronics assumes no responsibility or liability for any use of the information contained herein. Nothing in this document shall operate as an express or implied license or indemnity under the intellectual property rights of Hope Microelectronics or third parties. The products described in this document are not intended for use in implantation or other direct life support applications where malfunction may result in the direct physical harm or injury to persons. NO WARRANTIES OF ANY KIND, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MECHANTABILITY OR FITNESS FOR A ARTICULAR PURPOSE, ARE OFFERED IN THIS DOCUMENT. ©2006, HOPE MICROELECTRONICS CO.,LTD. All rights reserved.