January 2007
61
Intel
®
855GME Chipset and Intel
®
6300ESB ICH Embedded Platform Design Guide
4.1.5.4
Topology 2A: Open Drain (OD) Signals Driven by AND Gate–
PWRGOOD
The Topology 2A OD signal PWRGOOD, which is driven by an AND gate (Intel Pentium
M/Celeron M processor CMOS signal input), shall adhere to the following routing and layout
recommendations.
lists the recommended routing requirements for the PWRGOOD signal
of the Intel Pentium M/Celeron M processor. The routing guidelines allow the signal to be routed
as either micro-strip or strip-lines using 55
Ω
± 15 percent characteristic trace impedance. The
pull-up voltage for termination resistor Rtt is VCCP (1.05 V).
depicts the routing
illustration for Topology 2A.
Note:
The output from the AND Gate (AND of power supply PWRGD_3V and CPU VR__PWRGD)
shall be routed point-to-point to the Intel Pentium M/Celeron M processor’s PWRGOOD signal.
The routing from the Intel Pentium M/Celeron M processor’s PWRGOOD pin shall fork out to the
termination resistor, Rtt, and the AND gate. Segments L1 and L2 from
shall not T-split
from a trace from the Intel Pentium M/Celeron M processor pin.
Figure 18. Routing Illustration for Topology 1C
Table 13. Layout Recommendations for Topology 1C
L1
L2
L3
L4
Rs
R1
R2-
Rtt
Transmission
Line Type
0.5” – 12.0”
0” – 3.0”
0” – 3.0”
0.5” – 12.0”
330
Ω
± 5%
1.3 k
Ω
± 5%
330
Ω
± 5%
56
Ω
± 5%
Micro-strip
0.5” – 12.0”
0” – 3.0”
0” – 3.0”
0.5” – 12.0”
330
Ω
± 5%
1.3 k
Ω
± 5%
330
Ω
± 5%
56
Ω
± 5%
Strip-line
CPU
L1
L3
L2
Rs
3.3
3904
3904
L4
3.3
Q1
Q2
R1
R2
V_IO_RCVR
(System
receiver)
VCCP
Rtt
Figure 19. Routing Illustration for Topology 2A
B4871-01
+27
CPU_VR_PWRGD
PWRGD_3V
L1
L2
Rtt
VCCP
Содержание 6300ESB ICH
Страница 24: ...24 Intel 855GME Chipset and Intel 6300ESB ICH Embedded Platform Design Guide Introduction...
Страница 36: ...36 Intel 855GME Chipset and Intel 6300ESB ICH Embedded Platform Design Guide General Design Considerations...
Страница 102: ...102 Intel 855GME Chipset and Intel 6300ESB ICH Embedded Platform Design Guide...
Страница 122: ...122 Intel 855GME Chipset and Intel 6300ESB ICH Embedded Platform Design Guide...
Страница 152: ...152 Intel 855GME Chipset and Intel 6300ESB ICH Embedded Platform Design Guide System Memory Design Guidelines DDR SDRAM...
Страница 172: ...172 Intel 855GME Chipset and Intel 6300ESB ICH Embedded Platform Design Guide Integrated Graphics Display Port...
Страница 190: ...190 Intel 855GME Chipset and Intel 6300ESB ICH Embedded Platform Design Guide Hub Interface...
Страница 246: ...246 Intel 855GME Chipset and Intel 6300ESB ICH Embedded Platform Design Guide Intel 6300ESB Design Guidelines...
Страница 264: ...264 Intel 855GME Chipset and Intel 6300ESB ICH Embedded Platform Design Guide Platform Clock Routing Guidelines...
Страница 298: ...298 Intel 855GME Chipset and Intel 6300ESB ICH Embedded Platform Design Guide Schematic Checklist Summary...
Страница 318: ...318 Intel 855GME Chipset and Intel 6300ESB ICH Embedded Platform Design Guide Layout Checklist...