
44409
Rev.
1.70
October 10
AMD SP5100 Databook
SP5100 Power on Sequence and Timing
17
Power up Sequence Timing Notes
Note 1:
There is no specific power sequencing requirement other than those indicated in Note
2 below. The SP5100 power rails are grouped in four different voltages:
I.
+5 V, which includes V5_VREF
II.
+3.3 V, which includes VDDQ, VDD33_18 (IDE mode)
III.
+1.2 V, which includes AVDDCK_1.2V, AVDD_SATA, PLLVDD_SATA, PCIE_PVDD,
PCIE_VDDR, CKVDD_1.2V
IV.
+1.8 V
Note 2:
V5_VREF is used in the SP5100 for the 5-V PCI signal tolerance. VDDQ (+3.3 V) &
VDD33_18 (3.3 V) must not exceed V5_VREF by more than 0.6 V at any time during ramp up,
steady state, or ramp down. The suggested circuit below should be used to maintain
relationship between V5_VREF and VDDQ and VDD33_18.
D1
1K
1 µF
+3.3V_S0
+5V_S0
SB
V5_VREF
VDDQ
VDD33_18
SCHOTTKY DIODE
RECOMENDED
Figure 3-3: Circuit for Maintaining Proper Relationship bV5_VREF and VDDQ
Note 3:
The SP5100 will latch the straps after rising edge of SB PWR_GOOD only once. With
debouncing of SB PWR_GOOD, the latching of strap will occur at approximately ~10ms after
the rising edge of SB PWR_GOOD.
Note 4
: Typical time between A_RST# and PCIRST# is 75 ns. The measurement should be
done at 10% of both signals. Loading on the motherboard may cause the measurement at
90% be more than the spec.
Note 5
: The KBRST# should be de-asserted before A_RST# (LDT_RST#) is de-asserted.
Note 6:
Type II Standard and Debug straps will be latched after SB PWR_GOOD is asserted.
Type I straps are latched on resume reset rising edge. Refer to
for strap timing.
Note 7
: The SP5100 will not monitor the ALLOW_LDTSTP signal on power up. This signal is
only used on C3 transitions.
Note 8:
The PCI Clock may be stable before T11 min. under some conditions; however in all
cases, the PCI Clock is guaranteed to be stable only between T11 min and max.
Note 9:
The SP5100 will monitor internally the power down events and protect the internal
circuit during the power down event. This includes power down during the S3, S4, and S5
states. During an unexpected power failure or G3 state, the relationship between the 1.2 V
(VDD) and SB Power Good should be maintained to protect the internal logic of the SP5100.