The Analog Devices DS2401P is a silicon serial number IC designed for electronic registration and identification. It operates over a wide voltage range and communicates via the 1-Wire protocol.
The Analog Devices DS2401P+ is a silicon serial number IC providing a unique 64-bit registration number. It operates from 2.8V to 6.0V and communicates via the 1-Wire protocol.
The DS2401P+T&R is a silicon serial number IC from Analog Devices / Maxim Integrated. It provides a unique, factory-lasered 64-bit ROM code for identification.