1-TO-10, LVPECL/ECL FANOUT BUFFER

12

ICS853111BY REV. B SEPTEMBER 5, 2007

ICS853111B

LOW SKEW, 1-TO-10, DIFFERENTIAL-TO-2.5V, 3.3V LVPECL/ECL FANOUT BUFFER

This application note provides general design guide using

ICS853111B LVPECL buffer. Figure 6 shows a schematic example

of the ICS853111B LVPECL clock buffer. In this example, the

input is driven by an LVPECL driver. CLK_SEL is set at logic high

to select PCLK0/nPCLK0 input.

C4

0.1uF

C6 (Option)

0.1u

Zo = 50

R7

50

Zo = 50

R2

50

VCC

R1

50

VCC

VCC=3.3V

C7 (Option)

0.1u

R3

50

(U1-16)

U1

ICS853111

1

2

3

4

5

6

7

8

17

18

19

20

21

22

23

24

VCC

CLK_SEL

PCLK0

nPCLK0

VBB

PCLK1

nPCLK1

VEE

nQ6

Q6

nQ5

Q5

nQ4

Q4

nQ3

Q3

R4

1K

Zo = 50

C2

0.1uF

(U1-9)

R8

50

Zo = 50 Ohm

C8 (Option)

0.1u

+

-

C5

0.1uF

R10

50

R11

50

3.3V LVPECL

+

-

VCC

(U1-32)

R13

50

C1

0.1uF

Zo = 50 Ohm

R9

50

C3

0.1uF

(U1-25)

VCC

Zo = 50

(U1-1)

EXPOSED PAD

Expose Metal Pad

(GROUND PAD)

GROUND PLANE

SOLDER

SIGNAL

TRACE

SIGNAL

TRACE

THERMAL VIA

SOLDER MASK

The expose metal pad provides heat transfer from the device to

the P.C. board. The expose metal pad is ground pad connected

to ground plane through thermal via. The exposed pad on the

device to the exposed metal pad on the PCB is contacted through

solder as shown in Figure 7. For further information, please refer

to the Application Note on Surface Mount Assembly of Amkor’s

Thermally /Electrically Enhance Leadframe Base Package, Amkor

Technology.