bq29412

www.ti.com bq29410, bq29411, bq29412 bq29413, bq29414 bq29415, bq29419 SLUS669G – AUGUST 2005 – REVISED AUGUST 2008 VOLTAGE PROTECTION FOR 2-, 3-, OR 4-CELL Li-Ion BATTERIES (2nd-LEVEL PROTECTION) Check for Samples: bq29410, bq29411, bq29412, bq29413, bq29414, bq29415, bq29419 FEATURES 1 2-, 3-, or 4-Cell Secondary Protection Low Power Consumption ICC < 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. DCT PACKAGE (TOP VIEW) OUT 1 VDD 2 CD 3 VC4 4 8 ...