DS18B20 / DS1822 Sıcaklık Probu Kablosu

DS18B20/ DS1822, yaygın olarak kullanılan bir dijital sıcaklık sensörüdür. Çıkışı dijital bir sinyaldir, Küçük boyut özelliklerine sahip olan, düşük donanım yükü, güçlü anti-parazit yeteneği ve yüksek hassasiyet. The DS18B20 digital temperature sensor is easy to wire and can be used in a variety of situations after being packaged, boru tipi gibi, dişli tip, mıknatıs adsorpsiyon tipi, and stainless steel packaging type. Çeşitli modeller var, LTM8877 dahil, LTM8874 ve benzeri. As a digital temperature sensor, the DS18B20 does not require any external components when measuring temperature. It can directly output the measured temperature value of 9~12 bits (including sign bit). The temperature measurement range is -55~+125℃. The measurement accuracy is ±0.5℃ in the range of -10~+85℃, and the output measurement resolution is adjustable, up to 0.0625℃. Supporting "single-wire bus" teknoloji, only one general-purpose I/O port is required to complete communication with the microcontroller. The on-site temperature is directly transmitted digitally via a "single-wire bus", which greatly improves the system's anti-interference capability.

DS18B20, DS1822 "One-line bus" digital temperature sensor Same as DS1820. DS18B20 also supports "tek hatlı otobüs" arayüz, and the measurement temperature range is -55°C~+125°C, and the accuracy is ±0.5°C in the range of -10~+85°C. The accuracy of the DS1822 is ±2°C. The on-site temperature is directly transmitted digitally via the "tek hatlı otobüs", which greatly improves the system's anti-interference capability. Suitable for on-site temperature measurement in harsh environments, such as environmental control, equipment or process control, temperature measurement consumer electronics, vesaire. The new product supports a voltage range of 3V~5.5V, making system design more flexible and convenient. And the new generation of products is cheaper and smaller. Features of DS18B20 and DS1822 DS18B20 can be programmed with a resolution of 9~12 bits and an accuracy of ±0.5°C. Optional smaller package, wider voltage range. The resolution setting and the user-set alarm temperature are stored in EEPROM and are still saved after power off. The performance of DS18B20 is the best among the new generation products! The price-performance ratio is also excellent! The DS1822 is software compatible with the DS18B20 and is a simplified version of the DS18B20. The EEPROM that stores user-defined alarm temperature and resolution parameters is omitted, and the accuracy is reduced to ±2°C. It is suitable for applications with low performance requirements and strict cost control. It is an economical product. Following the early products of the "One Line Bus", the DS1820 opens up a new concept in temperature sensor technology. DS18B20 and DS1822 provide more choices in voltage, characteristics and packaging, allowing us to build an economical temperature measurement system that suits us.

Internal structure of ds18b20 temperature probe
The internal structure of DS18B20 mainly consists of four parts:
64-bit fotolitografi ROM, sıcaklık sensörü, non-volatile temperature alarm trigger TH and TL, configuration register.
The pin arrangement of DS18B20 is as follows
DQ dijital sinyal giriş/çıkış terminalidir; GND güç toprağıdır; VDD is the external power supply input terminal (parazitik güç kablolama modunda topraklanmış).
The 64-bit serial number in the photo etched ROM is photo etched before leaving the factory. DS18B20'nin adres seri kodu olarak kabul edilebilir.. 64 bit fotolitografi ROM'unun düzeni şu şekildedir:: ilk 8 bitkiler (28H) ürün tipi numarası, Sonraki 48 bitler DS18B20'nin kendisinin seri numarasıdır, and the last 8 bits are the previous 56-bit cyclic redundancy check code (CRC=X8 +X5+X4+1). The purpose of the photolithography ROM is to make each DS18B20 different, böylece birden fazla DS18B20 bir veri yoluna bağlanabilir.
DS18B20'deki sıcaklık sensörü sıcaklık ölçümünü tamamlayabilir. Örnek olarak 12 bit dönüşümü alın: it is provided in the form of a 16-bit sign-extended two's complement reading, 0,0625°C/LSB şeklinde ifade edilir, burada S işaret bitidir.
Bu, 12 bit dönüşümden sonra elde edilen 12 bit veridir, 18B20'nin iki adet 8 bitlik RAM'inde depolanan. İlk 5 bits in binary are sign bits if the measured temperature is greater than 0. These 5 bitler 0. Sadece ölçülen değeri şununla çarpın: 0.0625 gerçek sıcaklığı elde etmek için. Sıcaklık daha düşükse 0, bunlar 5 bitler 1, ve ölçülen değerin ters çevrilmesi gerekiyor, artı 1, ve sonra çarpılır 0.0625 gerçek sıcaklığı elde etmek için.
Örneğin, +125°C'nin dijital çıkışı 07D0H'dir, +25.0625°C'nin dijital çıkışı 0191H'dir, -25.0625°C'nin dijital çıkışı FE6FH'dir, ve -55°C'nin dijital çıkışı FC90H'dir.