PRODUCT SPECIFICATION
RC7100
3
Pin Descriptions
Pin Name
REF0:2
Pin Number
2, 1, 47
Type
OUT
Pin Function Description
Reference clock outputs running at a fixed frequency equal to
the reference crystal or external frequency (14.318MHz).
These operate from a 3.3V power source.
APIC clocks running at a fixed frequency equal to the reference
crystal or external frequency. It is usually 14.318MHz. These
operate from a 2.5V power source.
CPU clocks used to drive the CPU processor. These clock
outputs operate from a 2.5V power source.
Free-running PCI clock which is not affected by PCISTOP#.
PCI clocks for generating all PCI timing requirements. These
clock outputs operate from a 3.3V power source.
48MHz clocks are fixed frequency outputs for USB or super
I/O requirements.
Crystal oscillator input or external reference generator input.
Crystal oscillator output.
Selects 100MHz or 66MHz for CPU clocks. When this input is
at a “1” level, the CPU frequency will be 100MHz and if at a “0”
level the frequency will be 66MHz.
Control select pins for selecting different modes of operation.
PWRDWN# is an input pin used to power-down the chip when
low.
Stops PCI clocks at low state when low
Stops CPU clocks at a low state when low
SPREAD# is active low and when activated the CPU and PCI
clocks are spread from 0.5% below the maximum frequency to
the maximum frequency.
3.3V supply for PCICLK, PCICLKF, REF, 48MHz drivers and
PLL core
APIC0:1
44, 45
OUT
CPUCLK0:3
35, 36, 39, 40
OUT
PCICLKF
PCICLK0:6
7
OUT
OUT
8, 10, 11, 13, 14,
16, 17
22, 23
48MHz0:1
OUT
XTALIN
XTALOUT
SEL100/66#
4
5
25
IN
OUT
IN
SEL1, SEL0
PWRDWN#
26, 27
29
IN
IN
PCISTOP#
CPUSTOP#
SPREAD#
31
30
28
IN
IN
IN
VDDpci,
VDDref,
VDDcore,
VDD48MHz
VDDcpu,
VDDapic
VSSref,
VSSpci,
VSS48MHz,
VSScore,
VSScpu,
VSSapic
NC
9, 15, 19, 21, 33,
48
POWER
37, 41, 46
POWER
2.5V supply for CPU and APIC drivers
3, 6, 12, 18, 20,
24, 32, 34, 38,
43
GROUND
Ground
42
reserved
No connect - reserved for future use