Ds18b20 センサー プローブとケーブル

The ds18b20 temperature sensor probe has high accuracy. The temperature measurement accuracy can reach 0.01℃, and the temperature measurement accuracy in the wide temperature range is 0.1℃. Good stability and high precision in mass production.

The DS18B20 digital sensor probe and cable are easy to connect and can be used in a variety of situations after being packaged. Such as stainless steel straight pipe type, ねじ込みタイプ, magnet adsorption type, various models, LTM8877を含む, LTM8874など.
DS18B20 は一般的に使用されるデジタル温度センサーです. It outputs a digital signal and has the characteristics of small size, ハードウェアのオーバーヘッドが低い, strong anti-interference ability and high accuracy. Its appearance mainly changes depending on the application. The encapsulated DS18B20 can be used for cable temperature measurement, blast furnace water circulation temperature measurement, boiler temperature measurement, machine room temperature measurement, agricultural greenhouse temperature measurement, clean room temperature measurement, ammunition depot temperature measurement and other non-limit temperature occasions. Wear-resistant and impact-resistant, small in size, 使いやすい, with various packaging forms, it is suitable for digital temperature measurement and control of various small space equipment.

Main features of DS18B20 sensor probe
1. Main features of DS18B20
1.1. The adaptable voltage range is wider, voltage range: 3.0~5.5V, and can be powered by the data line in parasitic power mode
1.2. Unique single-wire interface method. When DS18B20 is connected to the microprocessor, it only needs one port line to achieve two-way communication between the microprocessor and DS18B20.
1.3. DS18B20 supports multi-point networking function. Multiple DS18B20 can be connected in parallel on the only three lines to achieve multi-point temperature measurement.
1.4. DS18B20 does not require any external components during use. All sensing components and conversion circuits are integrated into an integrated circuit shaped like a triode.
1.5. Temperature range -55℃～+125℃, accuracy is ±0.5℃ at -10～+85℃
1.6. The programmable resolution is 9~12 bits, and the corresponding resolvable temperatures are 0.5℃, 0.25℃, 0.125℃ and 0.0625℃ respectively, which can achieve high-precision temperature measurement.
1.7. At 9-bit resolution, the temperature can be converted into numbers in up to 93.75ms. At 12-bit resolution, the temperature value can be converted into numbers in up to 750ms, which is faster.
1.8. The measurement results directly output digital temperature signals and are serially transmitted to the CPU via the "one-line bus". 同時に, the CRC check code can be transmitted, which has strong anti-interference and error correction capabilities.
1.9. Negative voltage characteristics: When the polarity of the power supply is reversed, the chip will not be burned due to heat, but it will not work properly.

2. Appearance and internal structure of DS18B20 sensor
The internal structure of the DS18B20 sensor mainly consists of four parts: 64-bit photolithography ROM, 温度センサー, non-volatile temperature alarm triggers TH and TL, and configuration register.
The appearance and pin arrangement of DS18B20 are as follows:

DS18B20 pin definition:
(1) DQ is the digital signal input/output terminal;
(2) GND is the power ground;
(3) VDD is the input terminal of the external power supply (grounded in the parasitic power wiring mode).
3. Working principle of DS18B20
The reading and writing timing and temperature measurement principle of DS18B20 are the same as those of DS1820, except that the number of digits of the temperature value obtained is different due to different resolutions, and the delay time during temperature conversion is reduced from 2s to 750ms. The oscillation rate of high temperature coefficient crystal oscillator changes significantly with temperature changes, and the generated signal is used as the pulse input of counter 2. Counter 1 and the temperature register are preset at a base value corresponding to -55°C. Counter 1 counts down the pulse signal generated by the low temperature coefficient crystal oscillator. When the preset value of counter 1 decreases to 0, the value of the temperature register will be increased by 1, the preset value of counter 1 will be reloaded, and counter 1 will restart counting the pulse signals generated by the low temperature coefficient crystal oscillator. This cycle continues until counter 2 counts to 0, then stops accumulating the temperature register value. 現時点では, the value in the temperature register is the measured temperature. The slope accumulator in Figure 3 is used to compensate and correct the nonlinearity in the temperature measurement process, and its output is used to correct the preset value of counter 1.