1 Features
• 2-, 3-, and 4-series cell overvoltage protection
• External capacitor-programmed delay timer
• Factory programmed OVP threshold (threshold
range 3.85 V to 4.6 V)
• Output options: active high or open drain active
low
• High-accuracy overvoltage protection: ±10 mV
• Low power consumption ICC ≈ 1 μA
(VCELL(ALL) < VPROTECT)
• Low leakage current per cell input < 100 nA
• Small package footprint
– 8-pin WSON (2.00 mm x 2.00 mm)

2 Applications
• Notebooks
• UPS battery backup

3 Description
The BQ2947 family is an overvoltage monitor and
protector for Li-Ion battery pack systems. Each cell is
monitored independently for an overvoltage condition.
In the BQ2947 device, an external delay timer is
initiated upon detection of an overvoltage condition on
any cell. Upon expiration of the delay timer, the output
is triggered into its active state (either high or low,
depending on the configuration). The external delay
timer feature also includes the ability to detect an
open or shorted delay capacitor on the CD pin, which
will similarly trigger the output driver in an overvoltage
condition.
For quicker production-line testing, the BQ2947
device provides a Customer Test Mode with 67
reduced delay time.