Intel EP80579 Guide

Intel
®
EP80579 Integrated Processor Product Line May 2010
Order Number: 320068-005US 71
System Power Delivery Guide—Intel
®
EP80579 Integrated Processor Product Line
6.5.7 3.3V (VCC3)
The VCC3 (3.3V) power plane comes directly from 3.3V power rail delivered by the
power supply. This power plane is used for all 3.3V I/O functions that are not dedicated
to their own power rail. The plane provides power for the following interfaces:
• VCC3: Used for internal logic (ICH, CAN, SSP, SATA, GbE, Expansion Bus)
• VCCABGP033: Bandgap for internal PCI-Express
• VCCABG3P3_USB: Bandgap for internal USB logic
• VCCSATABG3P3: Bandgap for internal SATA logic
6.5.8 5V Voltage (VCC50)
The 5V power plane is connected directly to the +5.0V power rail delivered by the ATX
power supply unit. This plane is responsible for allowing 5V tolerance on some input
pins.
6.5.9 VCCRTC Reference
This is the 3.3 VSBY3_3 supply for the RTC well pin. The 3.3V can drop to 2.0V min. in
G3 state. This power is not expected to be shut off unless the RTC battery is removed
or completely drained.
6.5.10 Standby Voltages
6.5.10.1 2.5V Standby (VSBY2_5)
The VSBY2_5 is derived from the 5V Standby (VSBY5) power rail delivered by the ATX
power supply unit through a linear regulator. This rail provides power to the 2.5V
resume I/O logic.
6.5.10.2 1.2V Standby (VSBY1_2)
The VSBY1_2 is derived from the VSBY5 power rail delivered by the ATX power supply
unit through the VSBY2_5 linear regulator and a 1.2V linear regulator. This rail provides
power to the 1.2V resume I/O logic.
6.5.10.3 1.0V Standby (VSBY1_0)
The VSBY1_0 is derived from the VSBY5 power rail delivered by the ATX power supply
unit through the VSBY2_5 linear regulator and a 1.0V linear regulator. This rail provides
power to the PCI Express switch and GbE LAN resume I/O logic.
6.5.10.4 3.3V Standby (VSBY3_3)
The VSBY3_3 is derived from the 5V Standby (VSBY5) power rail delivered by the ATX
power supply unit through a linear regulator. This rail provides power to the 3.3V
resume I/O logic.
6.5.10.5 5.0V Standby (VSBY5)
The VSBY5 power plane comes directly off the 5V VSBY power rail from the ATX power
supply and has three functions. First, it provides power to component resume logic and
wake capable devices (e.g., USB, LAN, etc.). Second, it supplies power to the 1.8V
regulator, which supplies power to the memory devices during S3. Third, the VSBY5 is

Intel EP80579 Specifications

General

Brand	Intel
Model	EP80579
Category	Computer Hardware
Language	English