The DS28EA00 is a digital thermometer with 9-bit (0.5°C) to 12-bit (1/16°C) resolution and alarm function with nonvolatile (NV), user-programmable upper and lower trigger points. Each DS28EA00 has its unique 64-bit registration number that is factory-programmed into the chip. Data is transferred serially through the 1-Wire protocol, which requires only one data line and a ground for communication. The improved 1-Wire front end with hysteresis and glitch filter enables the DS28EA00 to perform reliably in large 1-Wire networks. Unlike other 1-Wire thermometers, the DS28EA00 has two additional pins to implement a sequence detect function. This feature allows the user to discover the registration numbers according to the physical device location in a chain, e.g., to measure the temperature in a storage tower at different height. If the sequence detect function is not needed, these pins can be used as general-purpose input or output. The DS28EA00 can derive the power for its operation directly from the data line (“parasite power”), eliminating the need for an external power supply.
The DS28EA00 digital thermometer provides temperature measurement from –40 °C to +85 °C with user‑selectable resolution of 9 to 12 bits. It features a unique 64‑bit factory‑programmed registration number, two general‑purpose I/O pins that can be used for sequence detection or as standard I/O, and can be powered directly from the 1‑Wire data line (parasite power) or from a local supply.
The device includes an 8‑pin uSOP package, full 1‑Wire command set for ROM and device‑specific functions, and non‑volatile alarm thresholds. Electrical characteristics such as supply voltage (3.0 V–5.5 V), maximum I/O sink current (20 mA), and detailed timing parameters are provided for design integration.
| Operating Temperature Range | -40 °C to +85 °C |
|---|---|
| Supply Voltage | 3.0 V to 5.5 V |
| Resolution | User‑selectable 9‑ to 12‑bit |
| Unique Identifier | 64‑bit registration number |
| PIO Pins | Two general‑purpose programmable I/O pins |
| Power Mode | Parasite power from data line or local VDD |
| Package | 8‑pin uSOP |
| Maximum I/O Sink Current | 20 mA |
It measures temperatures from –40 °C to +85 °C.
The device derives its operating power directly from the 1‑Wire data line without an external supply.
The resolution can be set to 9, 10, 11, or 12 bits.
Each device contains a unique 64‑bit registration number programmed at the factory.