8745BY

www.icst.com/products/hiperclocks.html

REV. B DECEMBER 2, 2004

10

Integrated

Circuit

Systems, Inc.

ICS8745B

The schematic of the ICS8745B layout example is shown in

Figure 5A. The ICS8745B recommended PCB board layout

for this example is shown in

Figure 5B. This layout example

is used as a general guideline. The layout in the actual sys-

U3

8745

1

2

3

4

5

6

7

8

17

18

19

20

21

22

23

24

SEL0

SEL1

CLK0

nCLK0

CLK1

nCLK1

CLK_SEL

MR

nQ1

Q1

GND

nQ2

Q2

VDDO

nQ3

Q3

SP = Space (i.e. not intstalled)

C16

10u

CLK_SEL

C2

0.1uF

VDDO=3.3V

C11

0.01u

RD3

SP

VDD

(U1-9)

VDD=3.3V

SEL[3:0] = 0101,

Divide by 2

RU3

1K

Zo = 50 Ohm

(77.76 MHz)

RU4

1K

RU5

SP

SEL0

RD4

SP

(155.5 MHz)

SEL2

RU6

1K

C4

0.1uF

C1

0.1uF

RU7

SP

3.3V PECL Driver

CLK_SEL

RD2

1K

RD5

1K

VDDO

SEL1

VDDO

(U1-28)

R8A

50

R7

10

R9

50

Zo = 50 Ohm

R2

100

Decoupling capacitor located near the power pins

R10

50

SEL3

RU2

SP

RD6

SP

R4

100

VDD

SEL0

(U1-32)

SEL2

C6

0.1uF

RD7

1K

Zo = 50 Ohm

SEL1

3.3V

(U1-16)

PLL_SEL

VDD

VDD

VDDA

(U1-22)

C5

0.1uF

Zo = 50 Ohm

LVDS_input

+

-

tem will depend on the selected component types, the den-

sity of the components, the density of the traces, and the

stack up of the P.C. board.