10

Integrated

Circuit

Systems, Inc.

ICS9FG1901

0962E—01/02/07

SMBusTable: FSB Frequency Select Register

Pin #

Name

Control Function

Type0

1

PWD

Bit 7

GRSEL_17

Group of 17 gear ratio select

RW

Gear Ratio

1:1

1

Bit 6

GRSEL_2

Group of 2 gear ratio select

RW

Gear Ratio

1:1

1

Bit 5

X

Bit 4

RW

Latch

Bit 3

FSBG_3

FSB Gear Ratio FS_3

RW

x

Bit 2

FSBG_2

FSB Gear Ratio FS_2

RW

0

Bit 1

FSBG_1

FSB Gear Ratio FS_1

RW

x

Bit 0

FSBG_0

FSB Gear Ratio FS_0

RW

1

SMBusTable: Output Control Register

Pin #

Name

Control Function

Type0

1

PWD

Bit 7

DIF_7

Output Control

RW

Hi-Z

Enable

1

Bit 6

DIF_6

Output Control

RW

Hi-Z

Enable

1

Bit 5

DIF_5

Output Control

RW

Hi-Z

Enable

1

Bit 4

DIF_4

Output Control

RW

Hi-Z

Enable

1

Bit 3

DIF_3

Output Control

RW

Hi-Z

Enable

1

Bit 2

DIF_2

Output Control

RW

Hi-Z

Enable

1

Bit 1

DIF_1

Output Control

RW

Hi-Z

Enable

1

Bit 0

DIF_0

Output Control

RW

Hi-Z

Enable

1

SMBusTable: Output and PLL BW Control Register

Pin #

Name

Control Function

Type0

1

PWD

Bit 7

RW

High BW

Low BW

1

Bit 6

RW

Bypass

PLL

1

Bit 5

DIF_13

Output Control

RW

Hi-Z

Enable

1

Bit 4

DIF_12

Output Control

RW

Hi-Z

Enable

1

Bit 3

DIF_11

Output Control

RW

Hi-Z

Enable

1

Bit 2

DIF_10

Output Control

RW

Hi-Z

Enable

1

Bit 1

DIF_9

Output Control

RW

Hi-Z

Enable

1

Bit 0

DIF_8

Output Control

RW

Hi-Z

Enable

1

Note: Bit 7 is wired OR to the HIGH_BW# input, any 0 selects High BW

Note: Bit 6 is wired OR to the SMB_A2_PLLBYP# input, any 0 selects Fanout Bypass mode

SMBusTable: Output Enable Readback Register

Pin #

Name

Control Function

Type0

1

PWD

Bit 7

R

X

Bit 6

R

X

Bit 5

R

X

Bit 4

R

X

Bit 3

R

X

Bit 2

R

X

Bit 1

R

X

Bit 0

R

X

Readback

Readback

Readback

Readback

Readback - OE5# Input

Readback - OE6# Input

Readback - OE_01234# Input

Readback

Readback

see note

PLL_BW# adjust

Readback - OE7# Input

8

-

-

Byte 1

Byte 0

DIF(16:0)

DIF(18:17)

FS_A_410 Latched Input

-

Reserved

See ICS9FG1901

Programmable Gear Ratios

Table

-

-

72

Readback - OE9# Input

Readback - OE8# Input

see note

BYPASS# test mode / PLL

Byte 3

Byte 2

Readback - SMB_A2_PLLBYP# In

Readback

Readback - HIGH_BW# In

Readback