Ac'97 Checklist; Miscellaneous Signals; Miscellaneous Signals Checklist - Intel 855GME Design Manual

®
Intel 855GME Chipset and Intel
Schematic Checklist Summary
12.4.12

AC'97 Checklist

Table 143.

AC'97 Checklist

Checklist Items
AC_BITCLK
AC_RST#
AC_SDOUT
AC_SDIN[2]
AC_SDIN[1],
AC_SDIN[0]
AC_SYNC
12.4.13

Miscellaneous Signals

Table 144.

Miscellaneous Signals Checklist

Checklist Items
CLK14
294
®
6300ESB ICH Embedded Platform Design Guide
Recommendations
No extra pull-down resistors
required.
Series termination resistor 33 Ω to
47 Ω from the motherboard codec
to the 6300ESB.
No extra pull-down resistor
required.
Use a jumper to an 8.2 K Ω pull-up
resistor. Should not be stuffed for
default operation.
Series termination resistor 0 Ω to 47
Ω to the on-board codec and to the
CNR.
Requires a 10 K Ω pull-down to
GND when a CNR card is used on
the platform.
Series termination resistors 33 Ω to
47 Ω from the AC_SDIN lines to the
6300ESB.
Internal pull-downs in the 6300ESB;
no external pull-downs required.
Series termination resistors 0 Ω to
47 Ω from the AC_SDIN lines to the
6300ESB.
No extra pull-down resistor
required.
Recommendations
Ensure this pin is connected to a 14
MHz clock output of the clock generator
(CK409) through a 33 Ω resistor
Interface Not Used
This pin has a weak
May leave as no
internal 20 K Ω nominal
connect
pull-down.
May leave as no Internal Pull-down
(9 K Ω -50 K Ω)
connect
This pin has a weak
internal 20 K Ω nominal
pull-down.
Strap Function: Safe Mode
(See the 6300ESB EDS
May leave as no
for more information)
connect
To properly detect a safe-
mode condition, a strong
pull-up will be required to
override this internal
pull-down.
This pin has a weak
internal 20 K Ω nominal
pull-down. For platforms
routing AC_SDIN[2] to
CNR, the additional
10 K Ω pull-down is
May leave as no
required to set the proper
connect
DC level for CNR card
switching circuitry.
Used for a codec
detection/addressing
mechanism on the CNR
card.
These pins have a weak
May leave as no
internal 20 K Ω nominal
connect
pull-down.
Some implementations
May leave as no add termination for signal
connect integrity. This signal is
platform specific.
Reason/Impact
Reason/Impact