WHAT IS AN IBUTTON?
by Maxim Integrated Products
An iButton is a computer chip with a globally unique address, factory-lasered at the time of manufacture (think of it as a URL for each iButton), enclosed in a 16mm stainless-steel case. iButtons can include read/write memory, clocks, thermometers and dataloggers.
They deliver or record data wherever needed. All this power and capability make iButtons ideal for a wide range of applications including environmental datalogging, access control, eCash transactions and asset tracking.
THE GLOBALLY UNIQUE TAG 281,000,000,000,000 DIFFERENT ADDRESSES!
An iButtons 64-bit address provides a simple, secure way of identifying a location or an item. It can serve as an electronic serial number that is never duplicated. With onboard memory, iButtons can also store critical information about an item or location, such as container contents, shipping destination or owner information.
RUGGED DURABILITY THAT LASTS AND LASTS!
iButtons bring unparalleled durability to datalogger applications. Expose one to high or low temperature extremes. Step on it. Drop it in water. There is no need to worry about destroying this datalogger because iButtons can withstand harsh indoor or outdoor environments. The durable iButton can be remissioned and reused for many years, significantly reducing operating costs.
iBUTTONS SIMPLE, LOW-POWER INTERFACE!
iButtons require a physical/electrical connection to whatever is reading or writing data. However, a novel digital communication scheme called a 1-Wire interface reduces the number of electrical contact points to just one, plus a ground reference. A single conductor for both power and data communications is all that is needed. Devices that read and write to iButtons have all their electrical components inside, with only the two electrical contact points exposed, separated by a wide gap. With the connection so simplified, you get very durable, dust- and moisture immune probes that interface to most surfaces. An iButton reader draws virtually no power in standby mode and less than 2mA during communication making it ideal for battery-powered devices such as handheld computers and PDAs. Reading an iButtons unique address takes no more than 5ms. Now users can finish their data collection tasks without having to worry about constantly changing batteries in their handheld device every few hours.