1 Features
1• Provides authentication of battery packs through
SHA-1 engine based HMAC
• 160-byte one-time programmable (OTP), 16-bytes
EEPROM
• Internal time-base eliminates external crystal
oscillator
• Low-power operating modes:
– Active: < 50 μA
– Sleep: 8 μA typical
• Single-wire SDQ interface
• Powers directly from the communication bus
• 6-lead VSON package

2 Applications
• Cellular phones
• PDA and smart phones
• MP3 players
• Digital cameras
• Internet appliances
• Handheld devices

3 Description
The bq26100 device provides a method to
authenticate battery packs, ensuring that only packs
manufactured by authorized sub-contractors are used
in the end application. The security is achieved using
the SHA-1 hash function inside the widely adopted
keyed-hash message authentication code (HMAC)
construction. A unique 128-bit key is stored in each
bq26100 device, allowing the host to authenticate
each pack.
The bq26100 device communicates to the system
over a simple one-wire bi-directional serial interface.
The 5-kbits/s SDQ bus interface reduces
communications overhead in the external
microcontroller. The bq26100 device also derives
power over the SDQ bus line via an external
capacitor.