FEATURES

• SMBus， version 1.0， compliant • Intel PAS Protected Storage support • Support Pentium and x86-based designs • Support SMBus Q-Buffering via PWRGD • Support SMBus selector for dual/triple DIMMs • 32KHZ input clock or Crystal input • Support 2 different power planes • 10 bytes scratch pad registers • 20 possible edge-sensitive programmable GPIOs per device • 8 possible Open Drain， Open Collector outputs • Programmable addresses for cascaded OZ998s • Supports 3.3V or 5V operation • Supports 5V tolerant LVTTL inputs （OZ998B） • LOW power hardware-driven speaker alarm outputs • SMBALERT# and SMI event outputs • 8 programmable interrupt inputs for SMI event or SMBALERT# • 8 Auto LED Flash （ALF） programmable outputs with 10% or 50% duty cycles

GENERAL DESCRIPTION O2Micro’s OZ998 Multi-DIMM Selector supports the switching between a primary SMBus and 3 other secondary SMBus. This function is particularly useful for DIMM devices and the support of Intel’s PAS （Preboot Authentication Service）。 In addition， the OZ998 can be configured to support two different power planes with different sets of General Purpose Input/Output （GPIO） signals， which supplements and enhances the power management capability of the chipsets， commonly found in an ACPI （Advanced Configuration of Power Interface） subsystem. Up to 20 possible GPIOs are available per device， and among those， GPIO［15:8］ are programmable to be either positive or negative-edged triggers to generate an SMIEVENT/SMBALERT# to the system. GPIO［7:0］ are programmable to be either a regular TTL level output， open drain or open collector output. To support over 20 GPIOs through cascading multiple OZ998 devices， configure each individual OZ998 device ID. Up to 8 Auto LED Flash （ALF） are available to drive an LED or speaker at a programmable frequency.