OEMs are moving away from NiCd and lead-acid batteries to embrace the more environmentally friendly Li-ion battery chemistries. Li-ion batteries are smaller, weigh less, and deliver longer battery life, but require monitoring and protection for safe use. Intersil’s ISL94203 3-to-8 cell battery pack monitor functions as a stand-alone battery management system for rechargeable Li-ion battery packs. It features an internal state machine has five pre-programmed stages to accurately control each cell of a battery pack to extend operating life.

The ISL94203 integrates high-side charge/discharge FET drive circuitry, which allows customers to securely ground reference the battery pack to their designs. The device  supports lithium-ion (Li-ion) and other battery chemistries used in medical mobility carts, wheelchairs, e-bikes, handheld power tools, vacuum cleaners and solar or renewable energy storage systems. The device accurately monitors, protects and cell balances rechargeable battery packs to maximize battery life and ensure safe charging and system operation.

Several programmable protection and monitoring features  safeguard battery packs from catastrophic events such as short circuit conditions and cell voltage shorts. It has an open wire check to ensure the IC is securely connected to the battery pack. The device also has a special protection feature that blows a polyfuse to render the battery pack inoperable in the event of a catastrophic failure. In addition to delivering diagnostic information, the ISL94203 can withstand battery pack hot plug events and support the full range of Li-ion chemistries.

Key features and specifications

•   High level of integration: cell voltage level shift, automatic cell balance, 14-bit ADC, current sense   monitor, power FET control, temperature sensor interface
•   Eight cell voltage monitors support Li-ion CoO₂, Li-ion Mn₂O₄, Li-ion phosphate and other    battery chemistries
•   Operates as a standalone solution or with a microcontroller
•   Integrated charge pump controls cutoff FETs used to charge/discharge battery pack
•   Multiple cell voltage protection options up to 4.8V
•   Programmable detection/recovery times for over-voltage, under-voltage, over-current and short    circuit conditions
•   Open wire detection
•   EEPROM storage for device configuration
•   Power saving algorithm activated when battery pack is not in use

The ISL94203 battery pack monitor is available now and comes in a 6mm x 6mm, 48-lead TQFN package. It is prices $2.19 in 1K quantities. The ISL94203EVKIT1Z evaluation kit is priced at $328 USD, and includes an evaluation board, interface board with USB to I2C interface, and software GUI that supports stand-alone operation or an external microcontroller.

Intersil Corporation
www.intersil.com