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AT88SC1608

0971G–SMEM–04/04

Description

The AT88SC1608 provides 17,408 bits of serial EEPROM memory organized as one

configuration zone of 128 bytes and eight user zones of 256 bytes each. This device is

optimized as a “secure memory” for the smart card market, secure identification for elec-

tronic data transfer, or components in a system, without the requirement of an internal

microprocessor.

The embedded authentication protocol allows the memory and the host to authenticate

each other. When this device is used with a host which incorporates a microcontroller

(e.g., AT89C51, AT89C2051, AT90S1200), the system provides an “anti-wiretapping”

configuration. The device and the host exchange “challenges” issued from a random

generator and verify their values through a specific cryptographic function included in

each part. When both agree on the same result, the access to the memory is permitted.

Figure 1. Security Methodology

Device

Host (Reader)

Card Number

Verify A

COMPUTE Challenge B

Challenge B

VERIFY (RPW)

DATA

VERIFY (WPW)

Write 0 or 1

COMPUTE Challenge A

Challenge A

VERIFY B

Read Password (RPW)

Write Password (WPW)

DATA