Product Introduction
The new generation HTU21D temperature and humidity sensor has established new standards in terms of size and intelligence: it is embedded in a double row flat no pin DFN package suitable for reflow soldering, with a bottom surface of 3x3mm and a height of 1.1mm. The sensor outputs a calibrated digital signal in standard I2C format. The HTU21D temperature and humidity sensor provides accurate and reliable temperature and humidity measurement data for 0EM applications. Temperature and humidity digital outputs are achieved through the interface and module connection of a microcontroller. The resolution of HTU21D can be changed by inputting commands (8/12 bit or even 12/14 bit RH/T), and the sensor can detect low battery status and output a checksum, which helps improve communication reliability.
Device Characteristics
| 參數(shù) Parameters | 符號(hào) Symbol | 參數(shù)值 Parameter values | 單位 Company |
| 儲(chǔ)藏溫度 Storage temperature | Tstg | -40 to +125 | ℃ |
| 供電電壓(峰值) Supply voltage (peak value) | Vcc | 3.8 | Vdc |
| 濕度測量范圍 Humidity measurement range | RH | 0 to 100 | %RH |
| 溫度測量范圍 Temperature measurement range | Ta | -40 to +105 | ℃ |
| VDD to GND | -0.3 to 3.6V | Vdc | |
| 數(shù)字I/0口引腳(DATA/SCK)to VDD Digital I/O port pin (DATA/SCK) to VDD | -0.3 to VDD+0.3 | Vdc | |
| 每個(gè)引腳輸入電流 Input current for each pin | -10 to +10 | mA |
(At T=25 ℃, Vd=3.3V)
| 特性 Characteristic | 符號(hào) Symbol | 最小值 Minimum value | 典型值 Typical values | 最大值 Maximum value | 單位 Company | |
| 分辨率 Resolving power | 12位 | 0.04 | %RH | |||
| 8位 | 0.7 | %RH | ||||
| 濕度測量范圍 Humidity measurement range | RH | 0 | 100 | %RH | ||
| 濕度測量精度(10%-95%RH) Humidity measurement accuracy (10% -95% RH) | 典型值 Typical values | ±2 | %RH | |||
| 最大值 Maximum value | ±3 | ±5 | ||||
| 濕度磁滯 Humidity hysteresis | ±1 | %RH | ||||
| 測量時(shí)間 Measurement time | 12位 | 14 | 18 | ms | ||
| 11位 | 7 | 9 | ms | |||
| 10位 | 4 | 5 | ms | |||
| 8位 | 2 | 3 | ms | |||
| 結(jié)露150小時(shí)后的恢復(fù)時(shí)間 Recovery time after 150 hours of condensation | t | 10 | s | |||
| 長期漂移 Long term drift | 0.5 | %RH/yr | ||||
| 響應(yīng)時(shí)間 Response time | TRH | 5 | 10 | s |
Product Description
| 引腳 Pin | 說明 Explain |
| 電源引腳 (VDD.GND) | HTU21 的供電范圍為 1.8VDC.3.6VDC，推薦電壓為3.0V。電源(VDD)和接地(VSS)之間須連接一個(gè)0.1uF的去耦電容，且電容的位置應(yīng)盡可能靠近傳感器。 The power supply range of HTU21 is 1.8VDC.3.6VDC, and the recommended voltage is 3.0V. A 0.1uF decoupling capacitor must be connected between the power supply (VDD) and ground (VSS), and the capacitor should be located as close as possible to the sensor. |
| 串行時(shí)鐘輸入 (SCK) | SCK 用于微處理器與 HTU21 之間的通訊同步。由于接口包含了完全靜態(tài)邏輯，因而不存在最小SCK 頻率。 SCK is used for communication synchronization between microprocessors and HTU21. Due to the interface containing completely static logic, there is no minimum SCK frequency. |
| 串行數(shù)據(jù) (DATA) | DATA 引腳為三態(tài)結(jié)構(gòu)，用于讀取傳感器數(shù)據(jù)。當(dāng)向傳感器發(fā)送命令時(shí),DATA 在 SCK 上升沿有效目在 SCK 高電平時(shí)必須保持穩(wěn)定。 DATA 在 SCK 下降沿之后改變。當(dāng)從傳感器讀取數(shù)據(jù)時(shí), DATA 在SCK 變低以后有效，且維持到下一個(gè) SCK的下降沿。為避免信號(hào)沖突，微處理器應(yīng)驅(qū)動(dòng) DATA 在低電平。需要一個(gè)外部的上拉電阻(例如: 10k9)將信號(hào)提拉至高電平。上拉電陽通常已包含在微處理器的 I/0 電路中。 The DATA pin is a three state structure used to read sensor data. When sending commands to sensors, DATA must remain stable at the SCK high level when the effective target is on the rising edge of SCK. DATA changes after the falling edge of SCK. When reading data from sensors, DATA becomes effective after SCK decreases and remains valid until the falling edge of the next SCK. To avoid signal conflicts, the microprocessor should drive DATA at a low level. We need an external pull-up resistor (e.g.: Lift the signal to a high level (10k9). The pull-up battery is usually included in the I/O circuit of the microprocessor. |
Design Description
If the SCL and SDA signal lines are parallel and very close to each other, it may cause signal crosstalk and communication failure. The solution is to place VDD or GND between two signal lines to separate them, or use shielded cables. In addition, reducing the SCL frequency may also improve the integrity of signal transmission. A 100nF decoupling capacitor must be added between the power pins (VDD, GND) for filtering. This capacitor should be placed as close as possible to the sensor.
Data fetch
The default resolution set inside the sensor is 12 bits for relative humidity and 14 bits for temperature. The output data of SDA is converted into a two byte packet, with the high byte MSB placed first (left aligned). Each byte is followed by a response bit. The two status bits, namely the last two bits of LSB, must be set to '0' before performing physical calculations.
The HTU21D is a low-cost, easy to use, highly accurate, digital humidity and temperature sensor. This sensor is ideal for environmental sensing and data logging and perfect for a weather stationsor humidor control systems. All you need is two lines for l2C communication and you'll have relative humidity readings and veryaccurate temperature readings as a bonus!
Product Photograph
Payment&Transportation
Official Certificate&Certificate
Multiple product supply
Company office environment
Warehouse Real Shot
Standard packaging
We also provide ：
| Part No | Manufacturer | Date Code | Quantity | Description |
| LM22676ADJ | NS | 19+ | 250 | SOP8 |
| TPS562201DDCR | TI | 22+ | 795500 | SOT23-6 |
| NJG1806K75 | JRC | 22+ | 500000 | DFN6 |
| TLV74318PDQNR | TI | 22+ | 402000 | X2SON-4 |
| NJG1801K75 | JRC | 22+ | 300000 | SMD |
| NJG1804K64 | JRC | 22+ | 300000 | DFN8 |
| LM27761DSGR | TI | 22+ | 151000 | WSON8 |
| TLV62565DBVR | TI | 22+ | 138000 | SOT23-5 |
| TPS613222ADBVR | TI | 22+ | 108000 | SOT23-5 |
| LNK625DG-TL | POWER | 22+ | 100000 | SOP-8 |
| OPA4322AIPWR | TI | 22+ | 100000 | TSSOP14 |
| TLV75528PDRVR | TI | 22+ | 99000 | WSON-6 |
| TPS7A2025PDQNR | TI | 22+ | 78500 | X2SON-4 |
| TLV62568DBVR | TI | 22+ | 72000 | SOT23-5 |
| STM32L051K8U6TR | ST | 22+ | 60000 | QFN32 |
| SKY66421-11 | SKYWORKS | 22+ | 56500 | QFN16 |
| TPS7A1111PDRVR | TI | 22+ | 54000 | WSON6 |
| TLV62569PDDCR | TI | 22+ | 52000 | SOT23-6 |
| TLV62569DBVR | TI | 22+ | 48000 | SOT23-5 |
| TPS23753APWR | TI | 22+ | 40000 | TSSOP14 |
| NB691GG-Z | MPS | 22+ | 30000 | QFN |
| SN74AHC1G02DBVR | TI | 22+ | 27939 | SOT-23 |
| TPS63000DRCR | TI | 22+ | 23238 | VSON10 |
| TLV75533PDRVR | TI | 22+ | 21500 | WSON6 |
| NB687BGQ-Z | MPS | 22+ | 20000 | QFN |
| A3916GESTR-T-1 | ALLEGRO | 22+ | 17150 | QFN-20 |
| TPS62135RGXR | TI | 22+ | 15000 | VQFN11 |
| TLE2022AMDR | TI | 0803+ | 12500 | SOP8 |
| TPS23756PWPR | TI | 22+ | 12000 | HTSSOP-20 |
