1FEATURES

• 2-, 3-, or 4-Cell Secondary Protection

• Low Power Consumption I CC < 2 μA

[VCELL(ALL) < V(PROTECT)]

• Fixed High Accuracy Overvoltage Protection

Threshold

– bq29410 = 4.35 V

– bq29411 = 4.40 V

– bq29412 = 4.45 V

– bq29413 = 4.50 V

– bq29414 = 4.55 V

– bq29415 = 4.60 V

– bq29419 = 4.30 V

• Programmable Delay Time of Detection

• High Power Supply Ripple Rejection

• Stable During Pulse Charge Operation

APPLICATIONS

• 2nd-Level Overvoltage Protection in Li-Ion

Battery Packs in:

– Notebook Computers

– Portable Instrumentation

– Portable Equipment

DESCRIPTION

The bq2941x is a secondary overvoltage protection

IC for 2-, 3-, or 4-cell lithium-ion battery packs that

incorporates a high-accuracy precision overvoltage

detection circuit. It includes a programmable delay

circuit for overvoltage detection time.

FUNCTION

Each cell in a multiple-cell pack is compared to an

internal reference voltage. If one cell reaches an overvoltage condition, the protection sequence

begins. The bq2941x device starts charging an

external capacitor through the CD pin. When the CD

pin voltage reaches 1.2 V, the OUT pin changes from a low level to a high level.