MiCo SnP
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1. MiCo SnP HT 01D 3 Reliability of Humidity Sensor 1 Normal operating Range The sensor works stable within recommended normal range see Figure 3 Long term exposures to conditions outside normal range especially at humidity gt 80 RH may temporarily offset the RH signal After return to normal range it will slowly return towards calibration state by itself 100 80 60 humidity ARH Normal Range 40 20 Relative 40 20 0 20 40 60 80 100 120 Temperature C Fig 4 Normal operating range 2 Hysteresis of Characteristics The graph shows the hysteresis curve of HT 01D sensor Considering the relative humidity of the sensor the hysteresis formula is give by Hysteresis Value H 10 RH 90 RH H 90 RH 10 RH The hysteresis variety of samples indicate AH lt 1 5 RH at each humidity point This result shows that the sensor satisfies our specification The meter is set to measure humidity value at Vpp 5V For the precise measurement we used the hygrometer and compared with the humidity of temperature humidity chamber 16000 Humidity value DEC N B382EEBE 10 20 30 40 50 60 70 80 90 100 Humidity RH Fig 5 Hysteresis of Humidity Sensor www micosnp com 5 16 MiCo SnP HT 01D 4 Dimension 1 HT 01D 8 0 mm ww CT SCL Serial Clock 6 Reconditioning Procedure The sensor exposed to extreme conditions or chemical solvents may have offset The fo2. C commands As detailed in below table there are two types of commands for user operating a HT 01D The Measurement Request MR is wake up command sent by the master for a new measurement cycle The Data Fetch DF command is used to fetch data in IC communication With the start of communication the entire output packet will be loaded in a serial output register The register will be updated after the communication is finished The output is always scaled to 14 bits programmed resolution IC command types Type Descriptions Measurement Request MR Start measuring cycle Data Fetch DF Used to fetch data in any digital mode Humidity modules do not carry out internal arithmetic operation to minimize on the current consumption A measurement process is carried out only after the command measuring request MR is received 1 Measurement Requests MR By a measurement request command the HT 01D is woke up and it executes a measuring cycle The measuring cycle begins with the temperature measurement followed by humidity measurement digital signal processing and finally writing the measured values into the output register The MR command consists of the address of the HT 01D with which the R W bit is transferred as O write The real signal of MR is 0x50 adding write bit 0 to address 0Ox28 After the humidity module is answered with ACK measurement started the master finalized the transfer with NACK stop condit
3. MiCo SnP HT 01D HT 01D Humidity amp Temperature Sensor Module User s Manual MiCo SnP www micosnp com 1 16 MiCo SnP HT 01D History 2013 03 30 Initial Release Manual Integration 2013 08 06 Addition output voltage table 2014 02 27 Interface circuit Fig 10 and I2C address Fig 12 MiCo SnP Co Ltd All rights reserved No part of this document may be reproduced in any form or by any means photocopying recording or otherwise without written permission from MiCo SnP Co Ltd Office 456 833 53 Mosan ro Daedeok myeon Anseong si Gyeonggi do South Korea TEL 82 31 612 6130 FAX 82 31 612 6212 Home Page URL http Awww micosnp com Printed in the Republic of Korea www micosnp com 2 16 MiCo SnP HT 01D 1 Features On Chip humidity amp temperature sensors Fully calibrated various output IPC Voltage Excellent long term stability Low power consumption Serial interface control 1 C Small size HT 01D Product Summary The HT 01D is a humidity amp temperature sensor The device includes a relative capacitive humidity sensor elements and a band gap temperature sensor with capacitive to voltage converter C V Converter This results in superior signal quality a fast response time and insensitivity to external disturbances at a very competitive price Each HT 01D is individually calibrated in a precision chamber The calibration coe
4. al Clock SCL The SCLK is used to synchronize the communication between a microcontroller and the HT 01D Since the interface consists of fully static logic there is no minimum SCL frequency 3 Serial Data SDA The SDA pin is used to transfer data in and out of the device Data changes after the falling edge and is valid on the rising edge of the serial clock SCL During transmission the SDAT line must remain stable while SCL is high An external pull up resistor is required to pull the signal high www micosnp com 8 16 MiCo SnP HT 01D 12 IC Interface For integration with the micro controller the HT 01D has a I C compatible interface which supports both 100 kHz and 400 kHz bit rate The I C slave address is programmed by default on 28 and can be adjusted in the entire address range of OO to 7Fy SE ee ee AN P Fiu tsupat tLow gt gt gt tupsta tuppat tHiGH tsusta tsusto Fig 11 IC Timing Diagram 1 C Parameters Parameter Symbol Start condition hold time relative to SCL edge tosa 01 f Minimum SCL clock low width tow 0 6 Minimum SCL clock high width THIGH 0 6 start condition setup time relative to SCL edge tsusTa Data hold time on SDA relative to SCL edge tHDDAT Data setup time on SDA relative to SCL edge 0 1 Bus free time between stop condition and start condition BUS 0 1 0 Stop condition setup time on SCL www micosnp com 9 16 MiCo SnP HT 01D 13
5. fficients are programmed into the memory These coefficients are used internally during measurements to calibrate the signals from the sensors The serial interface and internal voltage regulation allows easy and fast system integration Its small size and low power consumption makes it the ultimate choice for even the most demanding applications The device is supplied in single in line type devices Customer specific packaging options may be available on request Humidity Temperature Product Number Pin Type D Application HVAC Test amp Measurement Automotive Data Logging Consumer Goods Automation Weather Stations White Goods Humidifiers Medical www micosnp com 3 16 MiCo SnP HT 01D 2 Specification Table 1 Specification for humidity sensor Table 2 Specification for temperature sensor reonaw coon in oe mo oe Presta Operating Operating RH Range Range som ma a Accuracy RH Accuracy Seefiguwet3 Seefiguwet3 1 3 See figure 2 Hysteresis Y ARH Response time time 10 9 Typical Typical 9 Maximal Maximal 7 T6 X X5 34 3 2 1 0 0 20 40 60 80 100 40 20 0 20 40 60 80 100 120 Relative Humidity RH Temperature C Fig 1 Humidity accuracy at 25C Fig 2 Temperature accuracy 5 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 Temperature Fig 3 Maximal tolerance of relative humidity at different temperature www micosnp com 4 16
6. has not been fetched since the last measurement cycle Not applicable Data that has already been fetched since the last measurement cycle 3 Relative Humidity and Temperature Raw Data Collection www micosnp com 11 16 MiCo SnP HT 01D Raw data are collected for the HT 01D The Raw data should also be the average of several samples to minimize noise effects To collect relative humidity and temperature raw data in measurement the expression as follows The Humidity_ High and Humidity_Low bytes can be read in Humidity RH Humidity _High 5 0 x 256 Humidity Low 7 0 2 x 100 The Temp_High and the Temp_Low bytes can be read as temperature output in C Temp output C Temp_High 7 0 x 64 Temp_Low 7 2 4 2 x 165 40 Using bit range MSB LSB www micosnp com 12 16
7. ion Start Device Address 6 0 Fig 12 Measurement Request Command www micosnp com 10 16 MiCo SnP HT 01D 2 Data Fetch DF The DF command is began by the micro controller master as sending address bit 0x28 and read bit 1bit 1 The real signal is 0x51 The HT 01D sends back an acknowledgement ACK to indicate success The others data are two status bit and measurement data with humidity and temperature to sending a NACK stop condition by the master The first two bytes of measurement data contain the two status bits as MSB and then followed by the humidity value with 14 bits If the temperature data is also needed then these can be read after the humidity value The most significant 8 bits of the temperature value will be transferred as third byte Then the least significant 6 bits of the temperature value can be read as the fourth byte The last two bits are not used and should be masked away But if the temperature data is not needed the master can send a NACK signal If it doesn t appear state bit 00 does not communicate Start Device Address 6 0 Read ACK State Humi Data 13 8 ACK Humi Data 7 0 ACK Temp Data 15 0 ACK Temp Dataj7 2 NACK Stop Sele Start Condition Acknowledge Humidity Data Bit Ned Not Acknowledge State Status Bit 2bit Temperature Data Bit Stop Stop Condition Fig 13 Measurement Packet Reads Status Bit Table Sousse uot enon O Clipped normal output Data that
8. llowing reconditioning procedure may bring back to the calibrated state of device e Baking 100 C for 8 hours e Re Hydration 25 C gt 80 RH for 48 hours 7 Shipping details HT 01D was packaged in plastic trays Please be careful opening from side of the tray cover to avoid damage of sensors 8 Storage instructions The storage instructions must be followed precisely in order to guarantee specification Guarantees are one year storage of the sensor package Chemical vapors at high concentration in combination with long exposure times may offset the sensor reading www micosnp com 6 16 MiCo SnP HT 01D 9 Block Diagram Sensor Signal Conditioner EEPROM VDD 2 3V to 5 5V i Humidity VSS GND J Fig 9 HT 01D Block diagram 10 Operating Condition 1 Absolute Maximum Ratings 2 Operating Conditions External aoee between Vpp pin CvsupPLy and GND External Capacitance between Vcore Cvcore 10 110 nF pin and GND C Pull up Resistor 1 2 2 10 kQ SDA Load Capacitance 0 2 nF www micosnp com 7 16 MiCo SnP HT 01D 11 Circuit Interface Rp 1 10K Csupply D MCU Fig 10 HT 01D I C Interface 1 Power The HT 01D requires a voltage supply between 2 3 and 5 5V After power on the device needs 10ms to reach measurement state No commands should be sent If you send command at that time you cannot receive correct data from sensors 2 Seri
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