SB4002A_Data Sheet_EN

SB4002A
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PCI bus provides the PME# signal for Power Management Interface. PME# is used to request change of
power state of a device. It is an open drain signal which is asynchronous to CLK.
SB4002A provides the power management-related signal to the device in order to support the power
management interface in efficient manner. SB4002A provides the input signal PME_REQ and the output
signal PME_S. PME_REQ requests PCI bus to change the power state of the device, and PME_S shows the
current power state.
If PME_REQ is changed from low to high, the PME# signal is asserted (if PME_En is enabled). PME_S
outputs the current power state to the next device. The value is 1b for D0 state, or 1b for D3 state.