DS2252T_1 Datasheet, PDF (1/14 Pages) Dallas Semiconductor – Secure Microcontroller Module

DS2252T
DS2252T
Secure Microcontroller Module
FEATURES
• 8051 compatible microcontroller for secure/sensitive
applications
– 32K, 64K, or 128K bytes of nonvolatile SRAM
for program and/or data storage
– In–system programming via on–chip serial port
– Capable of modifying its own program or data
memory in the end system
• Firmware Security Features:
– Memory stored in encrypted form
– Encryption using on–chip 64–bit key
– Automatic true random key generator
– SDI Self Destruct Input
– Improved security over previous generations
– Protects memory contents from piracy
• Crashproof Operation
– Maintains all nonvolatile resources for over 10
years in the absence of power
– Power–fail Reset
– Early Warning Power–fail Interrupt
– Watchdog Timer
– Precision reference for power monitor
• Fully 8051 Compatible
– 128 bytes scratchpad RAM
– Two timer/counters
– On–chip serial port
– 32 parallel I/O port pins
• Permanently powered real time clock
PACKAGE OUTLINE
1
20 21
40
40-Pin SIMM
DESCRIPTION
The DS2252T is an 8051 compatible microcontroller
based on nonvolatile RAM technology. It is designed for
systems that need to protect memory contents from dis-
closure. This includes key data, sensitive algorithms,
and proprietary information of all types. Like other mem-
bers of the Secure Microcontroller family, it provides full
compatibility with the 8051 instruction set, timers, serial
port, and parallel I/O ports. By using NVRAM instead of
ROM, the user can program, then reprogram the micro-
controller while in–system. This allows frequent chang-
ing of sensitive processes with minimal effort. The
DS2252T provides an array of mechanisms to prevent
an attacker from examining the memory. It is designed
to resist all levels of threat including observation, analy-
sis, and physical attack. As a result, a massive effort
would be required to obtain any information about
memory contents. Furthermore, the “Soft” nature of the
DS2252T allows frequent modification of secure
information. This minimizes that value of any informa-
tion that is obtained.
ECopyright 1995 by Dallas Semiconductor Corporation.
All Rights Reserved. For important information regarding
patents and other intellectual property rights, please refer to
Dallas Semiconductor data books.
121395 1/14