ICS9FG1904B-1 Datasheet, PDF (6/22 Pages) Integrated Circuit Systems – Frequency Generator for CPU, PCIe Gen 1, PCIe Gen 2 & FBD

Integrated
Circuit
Systems, Inc.
ICS9FG1904B-1
ICS 9FG1904B-1 1:1 PLL Programming
Byte 9,
Byte9,
Byte 9,
CLK_IN
1:1 DIF
bit 2
bit 1
bit 0
(CPU FSB) Outputs
FSC
FSB
FS_A_410
MHz
MHz
1
0
1
100.00
100.00
0
0
1
133.33
133.33
0
1
1
166.67
166.67
0
1
0
200.00
200.00
0
0
0
266.67
266.67
1
0
0
333.33
333.33
1
1
0
400.00
400.00
1
1
1
Reserved
Notes
3
3
1
3
3
3
2
Notes:FS_A_410 = 1
1. Powerup Default for FS_A_410 = 1
2. Powerup Default for FS_A_410 = 0
3. Setting the exact FSB frequency after Power is required for best phase noise performance.
Output Divider Ratios
Binary
Desired Value to
Decimal write to
Value
Register
2
0000
3
0001
5
0010
7
0011
4
0100
6
0101
10
0110
14
0111
8
1000
12
1001
20
1010
28
1011
16
1100
24
1101
40
1110
56
1111
1255B—08/03/07
6