The document describes the features and characteristics of the DS1721 2-Wire Digital Thermometer and Thermostat, including temperature measurement range, resolution, conversion time, etc.
The DS1721 provides temperature measurements from –55 °C to +125 °C with ±1 °C accuracy and selectable resolution from 9 to 12 bits. It operates from a 2.7 V to 5.5 V supply and communicates via a 2‑wire serial interface that supports 3‑bit addressability for up to eight devices on the same bus.
The device includes a thermostat output (T OUT) that can be programmed with high (TH) and low (TL) temperature thresholds. Default setpoints are TH = 80 °C and TL = 75 °C, and the output polarity is configurable. Conversion time varies with resolution, with a 9‑bit conversion completing in 93.75 ms.
| Temperature range | -55 °C to +125 °C |
|---|---|
| Accuracy | ±1 °C |
| Resolution | 9‑ to 12‑bit (0.5 °C to 0.0625 °C) |
| Maximum conversion time (9‑bit) | 93.75 ms |
| Supply voltage range | 2.7 V – 5.5 V |
| Addressability | 3‑bit (up to 8 devices) |
| Default thermostat high setpoint (TH) | 80 °C |
It measures temperatures from –55 °C to +125 °C.
The DS1721 uses 3‑bit addressability, allowing up to eight sensors on the same 2‑wire bus.
The factory defaults are TH = 80 °C and TL = 75 °C.
A 9‑bit conversion completes in 93.75 ms.