Appendix A

Battery Backup Unit Option

Product Description

The Battery Backup Unit (BBU) option is an add-on module that protects the data in the RAID controller’s cache memory in the event of a power failure.

The battery backup module monitors the write back cache on the DAC960PG and DAC960PJ and provides power to the cache if it contains data not yet written to the drives when power is lost. The controller, with the BBU installed, occupies only one PCI slot on the host backplane.

Features

Some of the new features of the BBU include:

•Gas gauge circuit for battery charge monitoring

•Quick charge to replenish a drained battery

•Support for low-power EDO ECC RAM modules

Figure A-1. BBU Components

Manual No. 775012

A-1