AT88SC25616C-SI Atmel, AT88SC25616C-SI Datasheet - Page 8

• Manufacturer Part Number: AT88SC25616C-SI
• Manufacturer: Atmel

Specifications of AT88SC25616C-SI

• Operating Temperature (max): 85C
• Operating Temperature (min): -40C
• Package Type: SOIC
• Mounting: Surface Mount
• Pin Count: 8
• Operating Temperature Classification: Industrial
• Lead Free Status / RoHS Status: Not Compliant

Encryption
Supervisor Mode
Modify Forbidden
Program Only
Initial Device
Programming
8
AT88SC25616C
The data exchanged between the device and the host during read, write and verify
password commands may be encrypted to ensure data confidentiality.
The issuer may choose to require encryption for a user zone by settings made in the
configuration zone. Any one of four keys may be selected for use with a user zone. In
this case, activation of the encryption mode is required in order to read/write data in the
zone and only encrypted data will be transmitted. Even if not required, the host may
elect to activate encryption provided the proper keys are known.
Enabling this feature allows the holder of one specific password to gain full access to all
eight password sets, including the ability to change passwords.
No write access is allowed in a user zone protected with this feature at any time. The
user zone must be written during device personalization prior to blowing the security
fuses.
For a user zone protected by this feature, data within the zone may be changed from a
“1” to a “0”, but never from a “0” to a “1”.
To enable the security features of CryptoMemory, the device must first be personalized
to set up several registers and load in the appropriate passwords and keys. This is
accomplished through programming the configuration zone of CryptoMemory using sim-
ple write and read commands. To gain access to the configuration zone, the secure
code must first be successfully presented. For the AT88SC25616C device, the secure
code is $17 C3 3A. After writing and verfiying data in the configuration zone, the security
fuses must be blown to lock this information in the device. For additional information on
personalizing CryptoMemory, please see the application notes Programming CryptoM-
emory for Embedded Applications and Initializing CryptoMemory for Smart Card
Applications (at www.Atmel.com).
5017DS–SMEM–7/04