cs5535 National Semiconductor Corporation, cs5535 Datasheet - Page 532

• Manufacturer Part Number: cs5535
• Description: Geode Cs5535 Companion Multi-function South Bridge
• Manufacturer: National Semiconductor Corporation

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Electrical Specifications
6.3.1
All of the clocks in Table 6-7 indicate a minimum frequency
of zero. Specifically, there are no dynamic circuits with min-
imum clock speeds. Additionally, Active Hardware Clock
Gating (AHCG) (see Section 3.9 "Power Management" on
page 72) will turn off all or some of the system clocks at
selected
Note 1. Signal parameters are defined in Figure 6-1 "Clock Reference Definition" on page 530.
Note 2. Operationally, the minimum clock is 64.50 MHz. Operation out of the 66 MHz range indicated causes the CS5535
Note 3. Clock duty cycles not 100% tested. Guaranteed by design.
Note 4. For maximum system performance, this clock should be as high as possible up to the maximum indicated.
Note 5. The USB spec requires a controller accuracy of +/- 0.05% (500 ppm).
Note 6. Must be greater than half the MHZ14_CLK frequency.
Note 7. This clock is used as the system time base and hence should have the “typical” frequency indicated.
Note 8. This clock should be connected to the external codec output that is half the codec input clock of 24.478 MHz.
Note 9. Typically, connect these pins to a 32.768 kHz crystal. However, an external oscillator may be connected to the
Signal
MHZ66_CLK
PCI_CLK
MHZ48_CLK
LPC_CLK
MHZ14_CLK
AC_CLK
TCK
KHZ32_XCI
KHZ32_XCO
Clock Inputs
ATA Controller to operate out of ATA specification limits.
Must be at least four times faster than the KHZ32_XCI frequency.
KHZ32_XCI pin and driven to the maximum rate shown for testing. When operated with an external oscillator, leave
the KHZ32_XCO pin open. When operating with an external oscillator, input voltage on KHZ32_XCI (khz32_xci)
should swing rail-to-rail, that is, zero-to-V
at least 3.0 volts.
points
in
Parameter
Frequency
Rise/Fall Time
High/Low Time
Frequency
Rise/Fall Time
High/Low Time
Frequency
Rise/Fall Time
High/Low Time
Frequency
Rise/Fall Time
High/Low Time
Frequency
Rise/Fall Time
High/Low Time
Frequency
Rise/Fall Time
High/Low Time
Frequency
Rise/Fall Time
High/Low Time
Frequency
High/Low Time
time
to
(Continued)
save
Table 6-7. Clock Timing Parameters
power.
Min
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0
6
0
6
0
6
0
6
0
6
0
6
0
6
0
IO_VSB
The
14.31818
. With external oscillator, the input voltage high should always be
33 or 66
12.239
32.768
66.00
48.00
Typ
4.0
532
33
KHZ32_XCI/KH32XCO being the one exception to “off all”.
It always runs.
While the above discussion is accurate, there are minimum
clock requirements for proper system operation. These are
indicated in the Notes for each clock in Table 6-7.
66.50
49.25
15.00
None
67.50
None
None
None
None
13.00
None
15.00
None
None
1000
Max
34
2
2
2
2
2
2
2
Units
MHz
MHz
MHz
MHz
MHz
MHz
MHz
kHz
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
µs
Comment/Condition
Note 1 and Note 2.
Note 3.
Note 1 and Note 4.
Note 3.
Note 1 and Note 5.
Note 3.
Note 1, Note 4, and Note 6.
Note 3.
Note 1 and Note 7.
Note 3.
Note 1 and Note 8.
Note 3.
Note 1.
Note 3.
Note 1 and Note 9.
Note 3.
Revision 0.8