SLOWCLK / GPO0
Revision 1.71 June 9, 2000
F7, F10, F12-F14,
F6, F11, F15, G6,
K12, L6, L9-L12,
H6, H15, J6, J15,
R7-R8, R11, R14
G15, J9-J12, K9-
P6, P15, R6, R15
M15, N6, N15,
K6, K15, M6,
Power Good. Connected to the PWRGOOD signal on the Power Supply.
PCI Reset. Active low reset signal for the PCI bus. The VT82C686B will
assert this pin during power-up or from the control register.
Reset Drive. Reset signal to the ISA bus. Connect through an inverter to the
chipset north bridge RESET# input and to PCI bus RESET#.
Bus Clock. ISA bus clock.
Oscillator. 14.31818 MHz clock signal used by the internal Timer.
Slow Clock. .Frequency selectable if PMU function 4 Rx54[1-0] is nonzero
(set to 01, 10, or 11).
Core Power. 3.3V nominal (3.15V to 3.45V). This supply is turned on only
when the mechanical switch on the power supply is turned on and the
PWRON signal is conditioned high. This pin should be connected to the
same voltage as the CPU I/O circuitry. Internally connected to hardware
monitoring system voltage detection circuitry for 3.3V monitoring.
Ground. Connect to primary motherboard ground plane.
Suspend Power. Always available unless the mechanical switch of the power
supply is turned off. If the “soft-off” state is not implemented, then this pin
can be connected to VCC. Signals powered by or referenced to this plane are:
PWRGD, RSMRST#, PWRBTN#, SMBCLK, SMBDATA, SUSCLK,
SUSA# / GPO1, SUSB# / GPO2, SUSC#, SUSST1# / GPO6, GPI1 / IRQ8#,
GPI2 / BATLOW#, GPI3 / LID, GPI5 / PME#, GPI6 / SMBALRT#, GPI7 /
RTC Battery. Battery input for internal RTC (RTCX1, RTCX2)
Voltage Reference (5V 5%). For thermal sensing and 5V input tolerance.
Hardware Monitor Power.
(voltage monitoring, temperature monitoring, and fan speed monitoring).
Connect to VCC through a ferrite bead.
Hardware Monitor Ground. Connect to GND through a ferrite bead.
USB Differential Output Power.
(USBP0+, P0-, P1+, P1-, P2+, P2-, P3+, P3-). Connect to VCC through a
USB Differential Output Ground. Connect to GND through a ferrite bead.
RTC Crystal Input: 32.768 KHz crystal or oscillator input. This input is
RTC Crystal Output: 32.768 KHz crystal output
Power and Ground
Resets and Clocks
used for the internal RTC and for power-well power management logic.
Power for hardware monitoring subsystem
Power for USB differential outputs