Product details


Function Protection Number of series cells (Min) 2 Number of series cells (Max) 2 Features Overvoltage, Cell balancing, Single pin output drive Typical operating current (Typ) (uA) 3 Rating Automotive Vin (Max) (V) 16 TI functional safety category Functional Safety-Capable open-in-new Find other Battery protectors

Package | Pins | Size

VSON (DRB) 8 9 mm² 3 x 3 open-in-new Find other Battery protectors


  • 2-series cell secondary protection
  • Automatic cell imbalance correction with external enable control
    • ±30-mV enable, 0-mV disable thresholds typical
  • External capacitor-controlled delay timer
  • External resistor-controlled cell balance current
  • Low power consumption ICC < 3 µA typical (VCELL(ALL) < VPROTECT)
  • Internal cell balancing handles current up to 15 mA
  • External cell balancing mode supported
  • High-accuracy overvoltage protection:
    • ±25 mV with TA = 0°C to 60°C
  • Fixed overvoltage protection threshold: 4.30 V
  • Small 8L DRB package
  • Functional Safety-Capable
  • Automotive-qualified AEC Q100 grade two
open-in-new Find other Battery protectors


The BQ29209-Q1 device is a secondary overvoltage protection IC for 2-series cell lithium-ion battery packs that incorporates a high-accuracy precision overvoltage detection circuit and automatic cell imbalance correction.

The voltage of each cell in a 2-series cell battery pack is compared to a factory programmed internal reference voltage. If either cell reaches an overvoltage condition, the OUT pin changes from low to high state.

The BQ29209-Q1 can perform automatic voltage-based cell imbalance correction. Balancing can start when the cell voltages are different by nominally 30 mV or more and stops when the difference is nominally 0 mV. Cell balancing is enabled and disabled by the CB_EN pin.

open-in-new Find other Battery protectors

Technical documentation

star = Top documentation for this product selected by TI
No results found. Please clear your search and try again.
View all 5
Type Title Date
* Data sheet BQ29209-Q1 Voltage Protection with Automatic Cell Balance for 2-Series Cell Li-I datasheet (Rev. D) Sep. 30, 2020
Application note BQ29209-Q1 Function Safety Capable Manual Aug. 02, 2020
Technical article Is a LiFePO4 or Lithium-ion battery better for eCall systems? Oct. 25, 2016
Technical article Get to know your battery pack: Part 1 Sep. 28, 2015
Technical article The importance of battery management for eCall systems Jul. 02, 2015

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

CAD/CAE symbols

Package Pins Download
SON (DRB) 8 View options

Ordering & quality

Information included:
  • RoHS
  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring

Recommended products may have parameters, evaluation modules or reference designs related to this TI product.

Support & training

TI E2E™ forums with technical support from TI engineers

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​​​​​​​