AT88SA100S-SH-CZ-T ATMEL [ATMEL Corporation], AT88SA100S-SH-CZ-T Datasheet - Page 3

• Manufacturer Part Number: AT88SA100S-SH-CZ-T
• Description: Atmel CryptoAuthentication Battery Authentication Chip
• Manufacturer: ATMEL [ATMEL Corporation]

1.2
1.3
Fuse Map
The AT88SA100S chip incorporates 128 one-time fuses within the chip. Once burned, there is no way to reset the value of a
fuse. Fuses, with the exception of the manufacturing ID and serial number bits, which are initialized by Atmel, have a value of
one when shipped from the Atmel factory and transition to a zero when they are burned.
Table 1-1.
Fuse Lock Bits
Status Fuses
Chip Identification
The chip includes a total of 72-bits of information that can be used to distinguish between individual chips in a reliable manner.
The information is distributed between the ROM and fuse blocks in the following manner.
Serial Number
Manufacturing ID
Fuse #
0 – 7
8  83
84  87
87
88  95
96  127
The 128 Fuses in the Atmel AT88SA100S Chip are Arranged in the Following Manner:
Name
Fuse Lock Bits
Status Fuses
Status Fuses
Fuse Disable
Fuse MfrID
Fuse SN
These eight fuses can be used to prevent further writing of the status fuses. Bit 0, when burned, locks
Fuse[0-15] from being modified, Bit[1] locks Fuse[16-31] and so on up through bit five, which locks
Fuse[80-87]. Fuse[88-127] can never be modified with the BurnFuse command.
Note:
These fuses can be used to store various information which are not secret. Their value can always be
determined using the Read command. They can be individually burned using the BurnFuse command.
Two common usage models for these fuses are:
1.
2.
This 48-bit value is composed of ROM SN (16-bits) and Fuse SN (32-bits). Together they form a serial
number that is guaranteed to be unique for all devices ever manufactured within the Atmel
CryptoAuthentication family. This value is optionally included in the MAC calculation.
This 24-bit value is composed of ROM MfrID (16-bits) and Fuse MfrID (8-bits). Typically this value is
the same for all chips of a given type. It is always included in the cryptographic computations.
Consumption logging, i.e. burn one bit after every n uses, the host system keeps track of the
number of uses so far for this serial number since the last fuse burn.
Model number information. In this situation, the bits are written at the factory and their value is
locked to prevent modifications in the field. This method can also be used for feature enabling.
Burning bit zero has the effect of preventing any changes to the current value of the lock bits
Description
Each bit, when zero, locks the current value of the corresponding 16-bit block of the
fuse array, see below for more details
These fuses can be written with the BurnFuse command and can always be read with
the Read command. They are totally user-defined
These fuses can be written with the BurnFuse command and can always be read with
the Read command. They are user-defined, but have special significance for the Pause
Long command. See Section 6.3
The MAC command ignores the values of Fuse[0-86] while this fuse is an one
Once it is burned to zero, the BurnSecure command is disabled
See Section 1.3. Set by Atmel, cannot be modified in the field
See Section 1.3. Set by Atmel, cannot be modified in the field
Atmel AT88SA100S [DATASHEET]
8558F−CRYPTO−9/11
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