cy28551-3 Cypress Semiconductor Corporation., cy28551-3 Datasheet - Page 3

• Manufacturer Part Number: cy28551-3
• Description: Universal Clock Generator For Intel, Via And Sis
• Manufacturer: Cypress Semiconductor Corporation.

Document #: 001-05677 Rev. *D
Pin Description
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
Pin No.
VSSA
**DOC2
VSSCPU
CPUC1
CPUT1
VDDCPU
CPUC0
CPUT0
VTT_PWRGD#/PD
SDATA
SCLK
VDDREF
XOUT
XIN
VSSREF
**MODE/REF2
**FSC/REF1
**FSD/REF0
RESET_I#/SRESE
T#
**DOC1
**CLKREQ#B/PCI0 I/O,SE,
**CLKREQ#A/PCI1 I/O,SE,
VSSPCI
(continued)
Name
I/O, SE,
I/O, OD 3.3V-tolerant input for reset all of registers to default setting.
I/O,PD,
I/O,PD,
O, DIF Complement Differential CPU clock output.
O, DIF True Differential CPU clock output.
O, DIF Complement Differential CPU clock output.
O, DIF True Differential CPU clock output.
PWR 3.3V power supply for outputs.
PWR 3.3V power supply for outputs.
GND
I, PD
GND
GND
I, PD
GND
Type
I/O
PD
SE
SE
PD
PD
O
I
I
I
Ground for PLL.
Dynamic Over Clocking pin
0 = normal, 1 = Frequency will be changed depend on DOC register. Internal 150k
pull-down.
Ground for outputs.
Intel type SR output buffer.
Intel type SR output buffer.
Intel type SR output buffer.
Intel type SR output buffer.
3.3V LVTTL input. This pin is a level-sensitive strobe used to latch the HW strapping
pin inputs. After asserting VTT_PWRGD# (active LOW), this pin becomes a
real-time input for asserting power-down (active HIGH)
SMBus compatible SDATA
SMBus compatible SCLOCK.
14.318-MHz Crystal Output
14.318-MHz Crystal Input
Ground for outputs.
3.3V-tolerant input for selecting output/14.318-MHz REF clock output. Internal 150k
pull-down
0 = Desktop, 1 = Notebook
Intel Type-5 output buffer
3.3V-tolerant input for CPU frequency selection/14.318-MHz REF clock output.
Internal 150k pull-down
Intel Type-5 output buffer
Refer to DC Electrical Specifications table for Vil_FS and Vih_FS specifications.
3.3V-tolerant input for CPU frequency selection/14.318-MHz REF clock output.
Internal 150k pull-down
Intel Type-5 output buffer
Refer to DC Electrical Specifications table for Vil_FS and Vih_FS specifications.
3.3V LVTTL output for watchdog reset signal
Dynamic Over Clocking pin
0 = normal, 1 = Frequency will be changed depend on DOC register. Internal 150k
pull-down
3.3V tolerant LVTTL input for Output enable of PCIEX 4,5 via register
selection/33-MHz clock output. Internal 150k pull-down
Intel Type-3A output buffer
3.3V-tolerant LVTTL input for Output enable of PCIEX 6,7 via register
selection/33-MHz clock output. Internal 150K pull-down
Intel Type-3A output buffer
Ground for outputs.
Description
CY28551-3
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