BQ26150 Datasheet, PDF (6/16 Pages) Texas Instruments – BATTERY PACK SECURITY AND AUTHENTICATION IC FOR PORTABLE APPLICATIONS (bqSECURE)

bq26150
SLUS641A – JANUARY 2005 – REVISED JULY 2005
APPLICATION INFORMATION (continued)
Register Interface
Table 1. Memory Map
HDQ ADDRESS
NAME
FUNCTION
NONVOLATILE REGISTERS
0x7F – 0x70
GEN
General Purpose Memory
0x6F – 0x60
RSVD
Reserved
0x5F – 0x59
RSVD
Reserved
0x58
DL
Device Lock
0x57 – 0x51
RSVD
Reserved
0x50
SKI
Secret Key Index
0x4F – 0x4E
EDS
Encrypted polynomial seed (ES[15:0])
0x4D – 0x4C
EDP
Encrypted polynomial coefficients (EP[15:0])
0x4B – 0x48
EDK1
Encrypted device ID registers (EI[95:64])
0x47 – 0x40
EDK0
Encrypted device ID registers (EI[63:0])
0x3F – 0x3E
PDS
Plaintext polynomial seed(PS[15:0])
0x3D – 0x3C
PDP
Plaintext polynomial coefficients (PP[15:0])
0x3B – 0x38
PDK1
Plaintext device ID registers (PI[95:64])
0x37 – 0x30
PDK0
Plaintext device ID registers (PI[63:0])
RAM REGISTERS
0x2F – 0x1A
RSVD
Reserved
0x19
FACTORY Factory Reserved
0x18
CTRL
Authentication control register
0x17 – 0x06
RSVD
Reserved
0x05 – 0x04
AC
Authentication CRC value (AC[15:0])
0x03 – 0x00
RC
Random challenge registers (RC[31:0])
www.ti.com
Memory Descriptions
Reserved Registers (RSVD)–Addresses 0x6F–0x59, 0x57–0x51, 0x2F–0x1A, 0x17–0x06
Registers reserved for future use. Any read from these registers returns 0xFF.
General Use (GEN) – Addresses 0x7F – 0x70
General use memory allows battery manufacturer or other pack information to be stored in nonvolatile memory.
Device Lock (DL) – Addresses 0x58
When DL[7:4] is nonzero, any attempt to write the EDS, EDP, EDK1, PDS, PDP, or PDK1 registers is blocked.
When DL[3:0] is nonzero, any attempt to write to EDK0 or PDK0 is blocked. This feature allowed two entities to
write device information, providing for more secure programming. The lock takes effect immediately after the DL
register is written.
Secret Key Index (SKI) – Addresses 0x50
This non-volatile register can be used in the event that more than a single key is used by the host to decrypt the
EDP and EDK registers. For example, multiple pack manufacturers may be utilized to assembly packs for the
end equipment. Each pack manufacturer can be given a separate key (K_S), and key index value (I), to encrypt
the plaintext polynomial and device ID values. The host end equipment is then programmed with each secret key
(K_S) used by the various pack manufacturers. When authentication is attempted, the host reads the encrypted
polynomial, device ID, and key index values. The K_S used by the manufacturer with key index is then selected to
decrypt the values to plaintext.
6