HP Workstation x4000 hp workstation x4000 - Technical Reference manual - Windo - Page 33

System Board System Chipset Audio Chip (Analog Devices AD 1885) The on-board audio is provided by an Analog Devices AD1885 CODEC (AC97). The audio connections are: • headphone/lineout output (external) • line-in input (external) • microphone input (external) • CD-ROM input (internal) • internal speaker output (internal) The output to the internal speaker is amplified via an LM4871 audio amplifier to provide the power level needed by the speaker. A voltage regulator is used to provide a clean +5 volt supply for the CODEC's analog section, the internal speaker amplifier, and the microphone bias supply. The jacksense1 input of the CODEC is used to switch the audio output from the internal speaker to the headphone/lineout jack when a cable is plugged in the jack (this includes the keyboard's audio pass-through cable). Voltage dividers are provided on the line-in and CD-ROM inputs to meet PC99 specification requirements. Hardware Management Controller Chips The x4000 Workstation is monitored and managed by two chips on the SMBUS; • The Qlogic Zircon Lite micro-controller drives the Diag LEDs and the Power Button LED on the control panel. • The Winbond WB782D ASIC monitors voltage levels and control fans. • The SMBUS is a low frequency bus that communicates system state and error information among integrated circuits.. Chapter 2 33