DS1425 Datasheet | Dallas Semiconductor

FEATURES PACKAGE OUTLINE - Provides a unique 64- bit serial number and three 384 bit fields of password protected RAM - Intelligent response generator included - No external power required .. - Uses inexpensive 1- Wire TM protocol - Universally portable across platforms 16mm DESCRIPTION Authorization i Buttons are sophisticated microelectronics, sealed into miniature stainless steel cans, creating a low cost, portable medium for storing and controlling access to sensitive information. i Buttons are used with port adapters as a hardware based protection system for software. i Buttons help protect the right to copy software by actually protecting the right to execute it. Software can now be locked to a user, a machine, or an application with a plete audit trail and guaranteed uniqueness. The DS1425 provides a 64- bit unique ID number, and three 384 bit fields of password protected RAM. The DS1425 is used to provide nested levels of protection, or to protect multiple applications. Hardware munication with the i Buttons is conducted via a 1- Wire interface. The conversion from a PC I/O port to the 1- Wire interface is the responsibility of the port adapter. Software applications municate with the i Button using Dallas’ Access System, which is contained in any of the port adapter Developer’s kits. The Access System provides easy to use mands which are embedded into the application in order to utilize the i Button resources during run time. Each Dallas i Button is uniquely serialized with a 64- bit code that is laser- etched in the silicon. This unique ID provides a basic level of security, is traceable in the field, and makes it possible to identify the specific i Button in a field of many. The serial number is divided into three parts (see Figure 1). The 8- bit family code tells the Access System (and consequently the developer) what type of i Button is being used. The next 48 bits are lasered sequentially with no two numbers the same. The last 8 bits contain a Cyclic Redundancy...