TH06 ETC2

Document overview

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Technical content

Features

 Precision Relative Humidity Sensor  ± 5% RH (max), 0–80% RH  High Accuracy Temperature Sensor ±1 °C (max), –10 to 85 °C  0 to 100% RH operating range  –40 to +125 °C operating range  Wide o perating voltage (1.9 to 3.6 V)  L o w P ower Consumption 150 µA active current 60 nA standby current

Applications

 HVAC/R  Thermostats/humidistats  Respiratory therapy  White goods  Indoor wea ther sta t i ons

Description

 Factory-calibrated  I2C Interface  Integrated on-chip heater  9.1mmx10.8 mm SMT Module  Excellent long term stability  Optional factory-installed cover Low-profile Protection during reflo w Excludes liquids and particulates  Micro-environments/data centers  Automotive climate control and defogging  Asset and goods tracking  Mobile phones and tablets TH06: 9.1mmx10.8 mm SMT Module The TH06 I2C 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 an I2C Interface. 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 TH06 is reflow solderable. It can be used as a hardware- and software-compatible drop-in upgrade for existing RH/ temperature sensors , 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. The TH06 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.

  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 1.9 < VDD < 3.6 V; TA = –40 to 125 °C default conversion time unless otherwise noted.

  1. Initiating a RH measurement will also automatically initiate a temperature measurement. The total conversion time will
  2. No conversion or I2C transaction in progress. Typical values measured at 25 °C.
  3. 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
  2. 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 125 °C default conversion time unless otherwise noted.

  1. Initiating a RH measurement will also automatically initiate a temperature measurement. The total conversion time will
  2. No conversion or I2C transaction in progress. Typical values measured at 25 °C.
  3. 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
  2. Additional current consumption when HTRE bit enabled. See section “5.5. Heater” for more information

Table 3. I2C Interface Specifications1 1.9 ≤ VDD ≤ 3.6 V; TA = –40 to +125 °C unless otherwise noted.

  1. All values are referenced to VIL and/or VIH.
  2. Depending on the conversion command, the T H06 may hold the master during the conversion (clock stretch). At

highest I2C speed of 400 kHz the stretching will be <10 µs.

  1. Pulses up to and including 50 ns w ill be suppressed.

Table 3. I2C Interface Specifications1 (Continued) 1.9 ≤ VDD ≤ 3.6 V; TA = –40 to +125 °C unless otherwise noted.

  1. All values are referenced to VIL and/or VIH.
  2. Depending on the conversion command, the T H06 may hold the master during the conversion (clock stretch). At

highest I2C speed of 400 kHz the stretching will be <10 µs.

  1. Pulses up to and including 50 ns w ill be suppressed.

Figure 1. I2C Interface Timing Diagram

Table 4. Humidity Sensor 1.9 ≤ VDD ≤ 3.6 V; TA = 30 °C; default conversion time unless otherwise noted.

  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.

  1. 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.

  1. Drift due to aging effects at t y pical room conditions of 30 °C and 30% to 50% RH. May be impacted by dust, vaporized
  2. 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

Table 5. Temperature Sensor 1.9 ≤ VDD ≤ 3.6 V; TA = –40 to +125 °C default conversion time unless otherwise noted.

  1. 14b measurement resolution (default).
  2. 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

Table 6. Absolute Maximum Ratings1

  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. Typical Application Circuits

typical application circuit to achieve these functions. Figure 4. Typical Application Circuit for Relativ e Humidity and Temperature Measurement

Table 7. Typical Application Circuit BOM for Relative Humidity and Temperature Measurement

Figure 5. TH06 Block Diagram instrumentation, high reliability automotive and industrial systems, and cost-sens itive consumer electronics. The need to protect the senor from damage or contamination during the product life-cycle. The effects of humidity sensor “memory”. Each of these items is discussed in more detail in the following sections.

Sensor Accuracy Including Hysteresis,” shows the result of a typical sweep. Figure 6. Measuring Sensor Accuracy Including Hysteresis Contamination of the sensor by particulates, chemicals, etc. temperature by less than ± 0.05% ° C.

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com 14 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 fac tory calibration, and a sensor exposed to relatively high humidity will carry a positive offset relative to the factory calibration. This fa ctor 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 s ingle 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 affect by bak ing the device (see section “4.6. Bake/Hydrate Procedure” ). 4.4. PCB Assembly 4.4.1. Soldering Like most ICs, TH06 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:  TH06 devices are compatible with standard board assembly processes. Devices should be soldered us ing reflow per the recommended card reflow profile. See Section “10. 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. It is essential that the exposed pol y m e r 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. TH06 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 r e m o v e the Kapton tape. It can be left in place for the lifetime of the product, preventing liquids, dust or other contaminants from coming into c ontact with the polymer sensor film. See Section “8. Ordering Guide” for a list of ordering part numbers that include the cover. 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 TH06 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.

membrane providing up to IP67 compliant protection. Table 8. Specifications of Protective Cover Following this cycle, the sensor will return to normal operation in typical ambient conditions after a few days.

Table 9. I2C Slave Address Byte Table 10. I2C Command Table

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com 17 5.1. Issuing a Measurement Command The measurement commands instruct the TH06 to perform one of two possible measurements; Relative Humidity or Temperature. The procedure to issue any one of these commands is identical. While the measurement is in progress, the option of either clock s tretching (Hold Master Mode) or Not Acknowledging read requests (No Hold Mas ter Mode) is available to indicate to the master that the measurement is in progress; the chosen command c ode determines which mode is used. Optionally, a checksum b y t e can be returned from the slave for use in checking for transmission e rrors. The checksum b y t e will follow the least significant measurement byte if it is acknowledged by the master. The checksum byte is not returned if the master “not acknowledges” t he least significant measurement byte. The checksum byte is calculated using a CRC generator polynomial of x8 + x5 + x4 + 1, with an initialization of 0x00. The checksum byte is optional after initiating an RH or temperature measurement with commands 0xE5, 0xF5, 0xE3, and 0xF3. For all other commands, the checksum byte is not supported. Master Slave Sequence to perform a measurement and read back result (Hold Master Mode) S Slave Address W A Measure Cmd A Sr Slave Address R A Clock stretch during measurement MS Byte A LS Byte NA P A Checksum NA P

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com 18 Sequence to perform a measurement and read back result (No Hold Master Mode) S Slave Address W A Measure C m d A Sr Slave Address R NA Slave Address R NA Slave Address R A MS Byte A LS Byte NA P A Checksum NA P

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com 19 %RH = – 6 5.1.1. Measuring Relati v e Humidity Once a relative humidity measurement has been made, the results of the measurement may be c onverted to percent relative humidity by using the following expression: Where: %RH is the measured relative humidity value in %RH RH_Code is the 16-bit word returned by the TH06 A humidity measurement will always return XXXXXX10 in the LSB field. 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 expec ted behavior, and it is acceptable to limit the range of RH results to 0 to 100%RH in the host software by truncating values that are slightly outside of this range. 5.1.2. Measuring Temperature Each time a relative humidity measurement is made a temperature measurement is also made for the purposes of temperature compensation of the relative humidity measurement. If the temperature value is required, it can be read using command 0xE0; this avoids having to perform a second temperature measurement. The measure temperature commands 0xE3 and 0xF3 will perform a temperature measurement and return the measurement value, command 0xE0 does not perform a measurement but returns the temperature value measured during the relative humidity measurement. The checksum output is not available with the 0xE0 command. Sequence to read temperature value from previous RH measurement S Slave Address W A 0xE0 A Sr Slave Address R A MS Byte A LS Byte NA P

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com 20 T e m p e r a t u re (°C ) = – 46.85 The results of the temperature measurement may be converted to temperature in degrees Celsius (°C) using the following expression: 6 553 6 Where: Temperature (°C) is the measured temperature value in °C Temp_Code is the 16-bit word returned by the TH06 A temperature measurement will alwa y s return XXXXXX00 in the LSB field.

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com 21 5.2. Reading and Writing User Registers There is one user regis ter on the TH06 that allows the user to set the c onfiguration of the TH06. The procedure for accessing that register is described below. The checksum byte is not s upported after reading a user register. Sequence to read a register S Slave Address W A Read Reg Cmd A Sr Slave Address R A Read Data NA P Sequence to write a register S Slave Address W A Write Reg Cmd A Write Data A P 5.3. Firmware Revision The internal firmware revision can be read with the following I2C transaction: S Slave Address W A 0x84 A 0xB8 A S Slave Address R A FWR E V A NA P 5.5. Heater The TH06 contains an integrated resistive heating element that may be used to raise the temperature of the s ensor. This element can be used to test the sensor, to drive off condensation, or to implement dew-point measurement when the TH06 is used in conjunction with a separate temperature sensor such as another TH06 (the heater will raise the temperature of the internal temperature sensor). The heater can be activated using HTRE, bit 2 in User Register 1. Turning on the heater will reduce the tendency of the humidity sensor to accumulate an offset due to "memory" of sustained high humidity conditions.

Table 11. Register Summary

  1. A n y register not listed here is reserved and must not be written. The result of a read operation on these bits is
  2. Except where noted, reserved register bits w ill always read back as “1,” and are not affected by write operatio n s . For

from the RSVD bits should be written back unchanged during the write operation. device will no longer operate correctly.

Table 12. Device Ordering Guide N o te: The “A” denotes product revision A and “10” denotes firmware version 1.0.

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com 24 8. Pin Descriptions Pin Name Pin # Pin Power. This pin is connected to power on the circuit board. SDA 2 I2C data SCL 3 I2C clock GND 4 Ground. This pin is connected to ground on the circuit board through a trace. Do not connect directly to GND plane.

Tel:+86-755-82973805 Fax: +86-755-82973550 Email:sales@hoperf.com http://www.hoperf.com 25 9. Package Outline D i m e n s i o n M i n N o m M a x A 2 . 6 2 . 7 2 . 8 B 8 . 0 8 . 1 8 . 2 C 1 . 7 1 . 8 1 . 9 D 9 . 1 E 1 0 . 8 G 1 . 6 1 . 8 2 . 0 H 1 . 7 1 . 8 1 . 9 I 0 . 7 0 . 8 0 . 9 Notes: 1 . All dimensions are shown in millimeters (mm).

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.