DS28EA00：1-Wire Digital Thermometer with Sequence Detect and PIO

First 1-Wire Digital Temperature Sensor with Chain-Mode Function and GPIO

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.

Key Features

Digital Thermometer Measures Temperatures from -40°C to +85°C
Thermometer Resolution is User-Selectable from 9 to 12 Bits
Unique 1-Wire Interface Requires Only One Port Pin for Communication
Each Device has a Unique 64-Bit Factory-Lasered Registration Number
ROM Multidrop Capability Simplifies Distributed Temperature-Sensing Applications
Improved 1-Wire Interface with Hysteresis and Glitch Filter
User-Definable Nonvolatile (NV) Alarm Threshold Settings/User Bytes
Alarm Search Command to Quickly Identify Devices Whose Temperature is Outside of Programmed Limits
Standard and Overdrive 1-Wire Speed
Two General-Purpose Programmable IO (PIO) Pins
Chain Function Sharing the PIO Pins to Detect Physical Sequence of Devices in Network
Operating Range: 3.0V to 5.5V, -40°C to +85°C
Can be Powered from Data Line
8-Pin µSOP Package

DS28EA00: Typical Operating Circuit

Applications/Uses

Any Rack-Based Electronic System
Climate Control
Data communication equipment
Process Temperature Monitoring
Servers
Wireless Basestations

DataSheet

title	Download file
DS28EA00 Data Sheet	DS28EA00.pdf

Parametrics

Part Number	Sensor Type	Functions	Interface	Channels	Accuracy (±°C)	Parasite Pwr.	Temp. Thresh.	Temp. Resolution (bits)	Multi Droppable	Oper. Temp. (°C)	Package/Pins	Budgetary Price
Part Number	Sensor Type	Functions	Interface	Channels	Accuracy (±°C)	Parasite Pwr.	Temp. Thresh.	Temp. Resolution (bits)	Multi Droppable	Oper. Temp. (°C)	Package/Pins	See Notes
DS28EA00	Local	Chain Mode Function	1-Wire	One	0.5	Yes	Programmable (NV)	9 10 11 12	Yes	-40 to +85	µMAX/8	$2.30 @1k