4

ICS951601

Preliminary Product Preview

0663B—09/04/03

Byte 0: Functionality and frequency select register (Default = 0)

Serial Configuration Command Bitmap

Bit2 Bit7

Bit6

Bit5

Bit4

66MHZ 33MHz

FEATURES

FS4 FS3

FS2

FS1

FS0

00

0

0

0

66

33

-0.25 % down spread

00

0

0

1

66

33

-0.5 % down spread

00

0

1

0

66

33

-1.0 % down spread

00

0

1

1

66

33

-1.5 % down spread

00

1

0

0

66

33

+ 0.25 % center spread

00

1

0

1

66

33

+0.5 % center spread

00

1

1

0

66

33

+ 1.0 % center spread

00

1

1

1

66.6

33.3

+1.5 % center spread

01

0

0

0

67.32

33.66

2% over-clocking

01

0

0

1

68.64

34.32

4% over-clocking

01

0

1

0

69.96

34.98

6% over-clocking

01

0

1

1

72.6

36.3

10% over-clocking

01

1

0

0

65.27

32.63

2% under- clocking

01

1

0

1

63.96

31.97

2% under- clocking

01

1

1

0

62.6

31.3

2% under- clocking

01

1

1

1

60

30

2% under- clocking

10

0

0

0

66.6

33.3

-1.4 % down spread

10

0

0

1

66.6

33.3

-1.6 % down spread

10

0

1

0

66.6

33.3

-1.8 % down spread

10

0

1

1

66.6

33.3

-2.0 % down spread

10

1

0

0

66.6

33.3

+ 1.4 % center spread

10

1

0

1

66.6

33.3

+ 1.6 % center spread

10

1

1

0

66.6

33.3

+ 1.8 % center spread

10

1

1

1

66.6

33.3

+ 2.0 % center spread

Bit1

0-Normal

1-Spread spectrum Enabled

0

Bit0

0-Running 1-Tristate all outputs

0

Bit

PWD

00000

Bit

2,7:4

Bit3

0

0-Frequency and Spread is seleced by hardware select. Latched input

1-Frequency is seleced by Bit2, 7:4