BQ26150 Datasheet, PDF (7/16 Pages) Texas Instruments – BATTERY PACK SECURITY AND AUTHENTICATION IC FOR PORTABLE APPLICATIONS (bqSECURE)

bq26150
www.ti.com
SLUS641A – JANUARY 2005 – REVISED JULY 2005
Encrypted Device Seed (EDS) – Addresses 0x4F – 0x4E
The unique 16-bit CRC seed stored as ciphertext in public nonvolatile memory. The host reads this seed and
decrypts it using the shared key. The output of the decryption is the plaintext CRC seed that is used by the host
to initialize the authentication CRC.
Encrypted Device Polynomial Coefficients (EDP) – Addresses 0x4D – 0x4C
The unique 16-bit CRC polynomial stored as ciphertext in public nonvolatile memory. The host reads this register
pair and decrypts it using the shared key. The output of the decryption is the plaintext polynomial coefficients that
are used by the host to define the authentication CRC.
Encrypted Device ID (EDK) – Addresses 0x4B – 0x40
The unique 96 bit device ID used stored as ciphertext in public nonvolatile memory. The host reads this register
pair and decrypts it using the shared key. The output of the decryption is the plaintext device ID that are used by
the host to define the authentication CRC.
Plaintext Device Seed (PDS) – Addresses 0x3F – 0x3E
The unique 16 bit CRC seed stored as plaintext in private non-volatile memory. The seed registers are written to
the OTP at pack manufacturing or IC test. The plaintext seed is used by the bq26150 to initialize the
authentication CRC. Any attempt to read the plaintext seed registers will return data 0xFF.
Plaintext Device Polynomial Coefficients (PDP) – Addresses 0x3D – 0x3C
The unique 16 bit CRC polynomial stored as plaintext in private nonvolatile memory. The coefficients are written
to the OTP at pack manufacturing or IC test. The plaintext polynomial coefficients are used by the bq26150 to
define the authentication CRC. Any attempt to read the plaintext polynomial coefficients returns data 0xFF.
Plaintext Device ID (PDK) – Addresses 0x3B – 0x30
The unique 96 bit device ID used stored as plaintext in public nonvolatile memory. The device is written to the
OTP at pack manufacturing or IC test. The plaintext device ID is used by the bq26150 to calculate the
authentication CRC value. Any attempt to read the plaintext device ID returns data 0xFF.
Factory Reserved (FACTORY) – Address 0x19
This register is used internally to TI for simple identification. Writes are not permitted, and reads return a random
value.
Control Register (CTRL) – Address 0x18
NAME
POR STATUS
BIT 7
CPASS
0
BIT 6
OPASS
0
BIT 5
RSVD
0
BIT 4
RSVD
0
BIT 3
RSVD
0
BIT 2
POR
1
BIT 1
DONE
0
BIT 0
AUTH
0
CPASS
Writing the bit to a 1 enables the Continuous HDQ Pass Through mode. All communication then
passes through the HDQP pin, allowing the host to reach a 2^nd HDQ based device. The CPASS bit
is cleared when the bq26150 detects three consecutive breaks.
OPASS
Writing this bit to a 1 enables the One Time HDQ Pass Through mode. The next 16 valid bits of
communication passes through the HDQP pin, allowing the host to reach a 2^nd HDQ based device.
The OPASS bit is cleared following the 16^th valid data bit or when three consecutive breaks are
sent from the host.
RSVD
Reserved – These bits are available for future functions. These bits (5, 4, and 3) should be written
to 0 when the host system writes to the control register. These bits always return a 0 when the host
reads from the control register
POR
The POR bit is set to 1 by the bq26150 following a Power on Reset. This is a flag to the host that
V_CC was less than V_(POR) for some period of time. The device undergoes a full reset on a POR
condition. The host must clear the bit. The host may set this bit, but it has no effect on the
bq26150.
7