Cell-Balancing ICs Simplify Li-Ion Battery-Pack Design

May 30, 2007 2:22 PM

Intersil’s single-chip ISL9208 and ISL9216/17 chipset are integrated analog front ends for cell balancing and overcurrent protection in multi-cell Li-ion battery packs. The cell balancing allows the microcontroller to keep cell capacities matched to increase the battery pack’s operating time and extend battery life. The ISL9208 is recommended for five- to seven-cell (18-V to 28-V) battery packs, and the ISL9216/17 chipset is recommended for seven- to twelve-cell (28-V to 50-V) battery packs. These devices can replace up to 17 FETs, 12 diodes, 53 resistors and 31 capacitors.

The devices also provide critical protection through the ability to detect short circuits and overcurrent conditions, and automatically shut down the power FETs when necessary. The ISL9208 is available in a 32-lead, 5-mm x 5-mm QFN configuration starting at $2.33 each; the ISL9216 is available in a 2-lead, 5-mm x 5-mm QFN package starting at $3.08 each; and the ISL9217 is available in a 4-mm x 4-mm 24-lead QFN configuration starting at $3.01 each, all in quantities of 100 to 1000.