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.