SLVSJV2 September   2025 BQ79881-Q1

ADVANCE INFORMATION  

  1.   1
  2. 1Features
  3. 2Applications
  4. 3Description
  5. 4Device and Documentation Support
    1. 4.1 Device Support
      1. 4.1.1 Third-Party Products Disclaimer
    2. 4.2 Receiving Notification of Documentation Updates
    3. 4.3 Support Resources
    4. 4.4 Trademarks
    5. 4.5 Electrostatic Discharge Caution
    6. 4.6 Glossary
  6. 5Mechanical, Packaging, and Orderable Information
    1. 5.1 Package Option Addendum
    2. 5.2 Tape and Reel Information
    3. 5.3 Mechanical Data

3 Description

The device can be used to measure divided down high voltage nodes in a battery system. It can measure voltages across Fuses and Contactors, and it can check isolation voltages in battery junction box (BJB) systems. The device has four integrated current sense paths supporting low side shunt resistors. Coulomb counting is available for accurate SOC calculation. There are 18 GPIOs/auxiliary inputs that can be used for HV measurements, thermistor measurements and driving relays. There are 4 SW outputs that can be used to drive MOSFET switches in the measurement path. The device can function as a SPI and I2C HUB and interface with up to 8 separate SPI devices/groups. Over current protection response can be achieved autonomously using OC Pins for fast reaction in dangerous over current events. The isolated bi-directional daisy chain ports support both capacitor and transformer based isolation. The device can also communicate with MCU over SPI.

Package Information
PART NUMBERPACKAGE(1)BODY SIZE (NOM)
BQ79881-Q1HTQFP (48-pin)7mm × 7mm
(1) For all available packages, see the orderable addendum at the end of the data sheet.

BQ79881-Q1 Simplified System Diagram

Simplified System Diagram