The DS18B20 Digital Thermometer provides 9 to 12–bit centigrade temperature measurements and has an alarm function with nonvolatile user-programmable upper and lower trigger points. The DS18B20 communicates over a 1-Wire bus that by definition requires only one data line (and ground) for communication with a central microprocessor. It has an operating temperature range of –55°C to +125°C (–67°F to +257°F).
The DS18B20 provides 9‑ to 12‑bit temperature measurements over a –55 °C to +125 °C range and includes a non‑volatile alarm function. Each device carries a unique 64‑bit ROM code, allowing many sensors to share a single 1‑Wire bus.
Power can be supplied from the data line (parasite power) or an external Vpp supply (3.0 V‑5.5 V). The device supports multiple packages (TO‑92, 8‑pin SO, uSOP) and offers configurable resolution, conversion time, and EEPROM‑stored alarm thresholds.
| Temperature range | -55 °C to +125 °C |
|---|---|
| Accuracy | ±0.5 °C from –10 °C to +85 °C |
| Resolution | User‑selectable 9‑12 bits |
| Power supply range | 3.0 V to 5.5 V |
| Maximum conversion time (12‑bit) | 750 ms |
The DS18B20 powers up with a default resolution of 12‑bit.
Because each device has a unique 64‑bit code, the number of devices that can be addressed on one bus is virtually unlimited.
Yes, it can be powered from the data line in parasite‑power mode, eliminating the need for a separate supply.
A 12‑bit conversion takes up to 750 ms.