DS18B20U

DS18B20U is a variant of Maxim/Dallas’ DS18B20 digital temperature sensor. It uses a 1‑Wire interface on a single data line (plus ground; optional Vdd) and can operate in parasite power mode or with a dedicated supply. Temperature range is -55 to +125 °C; 9–12‑bit resolution (12‑bit default) with typical accuracy around ±0.5 °C at 25 °C. Each device has a unique 64‑bit ROM code, allowing multiple sensors on one bus. Communication follows the 1‑Wire protocol (ROM commands, Convert T, Read Scratchpad). Widely supported by microcontrollers (Arduino, Raspberry Pi, etc.) with libraries such as OneWire and DallasTemperature. The “U” suffix generally denotes a packaging/vendor variant and is functionally equivalent to DS18B20; always check the datasheet for exact packaging and electrical limits.

DS18B20U features (TO-92 3-pin 1‑Wire digital thermometer):
- 1‑Wire interface with a unique 64‑bit ROM code (family 28h) on the bus (up to 125 devices per bus).
- Temperature range: −55°C to +125°C.
- Resolution: 9–12 bits (0.5°C to 0.0625°C).
- Typical accuracy: about ±0.5°C from −10°C to +85°C.
- Programmable alarm thresholds TH and TL (alarm flags; stored in scratchpad/EEPROM).
- Scratchpad memory includes temperature, TH/TL, and configuration; can copy to nonvolatile EEPROM.
- Power options: external Vdd (3.0–5.5V) or parasitic power from the data line (needs pull-up).
- Conversion time scales with resolution (12-bit up to ~750 ms; 9-bit ~93.75 ms; 10/11-bit between).
- Package: DS18B20U in TO-92 style (3-pin).
- Applications: thermostats, HVAC, data loggers, environmental sensing.

- Pin count: 3 (TO-92 package, DS18B20U)
- Pinout (flat face, left to right): GND, DQ, VDD
- Function: 1-Wire digital temperature sensor/thermometer (−55°C to +125°C; 9–12-bit resolution); uses 1-Wire bus; can be powered from VDD or via parasite power on DQ.

- Manufacturer: Dallas Semiconductor (the DS18B20 was originally made by Dallas Semiconductor; the company was acquired by Maxim Integrated in 2001, and Maxim was later acquired by Analog Devices in 2021).
- What kind of company: a semiconductor company that designs and manufactures integrated circuits and related electronics components (sensors, memory, analog/digital ICs).

DS18B20U is the TO-92 packaged version of the DS18B20 1‑Wire digital thermometer. Common applications:
- 1‑Wire multi‑point temperature sensing in microcontroller/embedded systems
- Data logging and environmental monitoring (weather stations, greenhouses, agriculture)
- Home automation and smart appliances (HVAC, refrigerators, ovens)
- Industrial monitoring (server racks, cabinets, motors, process control)
- Refrigeration/food storage temperature surveillance
Notes: uses a single 1‑Wire bus; supports parasite power; suitable for low‑cost, multi‑sensor deployments.

DS18B20U is the TO-92 (3-pin) through-hole package version of the DS18B20.