bq29440, bq2944L0 bq29441, bq29442, bq29443, bq29449, bq2944L9
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SLUSA15C – JUNE 2010 – REVISED NOVEMBER 2010...
bq29440, bq2944L0 bq29441, bq29442, bq29443, bq29449, bq2944L9
www.ti.com
SLUSA15C – JUNE 2010 – REVISED NOVEMBER 2010
Voltage Protection for 2-Series, 3-Series, or 4-Series Cell Li-Ion Batteries
(Second-Level Protection)
Check for Samples: bq29440, bq2944L0, bq29441, bq29442, bq29443, bq29449, bq2944L9
FEATURES
1
2-Series, 3-Series, or 4-Series Cell Secondary Protection
External Capacitor-Controlled Delay Timer
Low Power Consumption ICC < 2 µA Typical [VCELL(ALL) < VPROTECT]
High-Accuracy Over
voltage Protection: ±25 mV with TA = 0°C to 60°C
Fixed Over
voltage Protection Thresholds: 4.30 V, 4.35 V, 4.40 V, 4.45 V, 4.50 V
Small 8L QFN Package
APPLICATIONS
Second-Level Protection in Li-Ion Battery Packs – Notebook Computers – Power Tools – Portable Equipment and Instrumentation
DESCRIPTION
The bq2944x is a secondary over
voltage protection IC for 2-series, 3-series, or 4-series cell Li-Ion battery packs that incorporates a high-accuracy precision over
voltage detection circuit.
FUNCTION
The
voltage of each cell in a battery pack is compared to an internal reference
voltage. If any cells reach an over
voltage condition, the bq2944x device starts a timer that provides a delay proportional to the capacitance on the CD pin. Upon expiration of the internal timer, the OUT pin changes from a low state to a high state. An optional latch configuration is available that holds the OUT pin in a high state indefinitely after an over
voltage condition has satisfied the speci...