1FEATURES
• Serial Non-Volatile Memory (NVM)
– 512 Byte (4Kb) EEPROM
– Provides Battery Pack NVM storage for
bq27505-E1 Fuel Gauge:
– Manufacturing Data
– Operational History
– Resistance Tables
– State of Health Information
• Single Wire HDQ Communications Port
• Integrated 2.5V LDO Linear Regulator
– Ultra-low power “shutdown” mode (1μA
Typical) via auto-timeout and/or host
command
– Wake up from shutdown via HDQ break
• Internal Die-Temperature Sensor
– ±5°C Range = –40°C to 85°C
– Raw AD to Temperature Conversion
Performed by Host Firmware
• Package
– 12-pin, 1490 × 2350 μm WCSP (YZG),
0.625mm Max Thickness, 0.5mm Pitch

DESCRIPTION
The Texas Instruments bq2028 serial 4Kb nonvolatile
memory (EEPROM) with integrated temperature
sensor and LDO linear regulator provides pack-side
memory storage and temperature monitoring for a
single-cell system-side battery fuel gauge solution
such as the bq27505-E1.
The bq2028 communicates with the bq27505-E1
gauge over a single-wire HDQ interface with a
minimal overhead protocol yet ensures error free data
transfer.