The ISL9216 and ISL9217 chipset provides overcurrent
protection and voltage monitoring for multi-cell li-ion battery
packs consisting of 8 to 12 cells. When used together, these
devices provide integrated overcurrent protection circuitry,
short circuit protection, an internal voltage regulator, internal
cell balancing switches, cell voltage level shifters, and drive
circuitry for external FET devices that control pack charge
and discharge. Level shifting of the analog output voltage
from the upper cells and communication between the chips
is handled automatically.
Overcurrent and short circuit thresholds reside in internal
RAM registers and are selected independently via software
using an I2C serial interface. Detection and time-out delays
can be individually varied using internal registers.
Using an internal analog multiplexer, the device provides
monitoring of cell voltage by a separate microcontroller with
A/D converter. Software on this microcontroller implements
all battery control functionality, except for overcurrent and short circuit shutdown.