ICS853111B Datasheet, PDF (12/19 Pages) Integrated Circuit Systems – LOW SKEW, 1-TO-10 DIFFERENTIAL-TO-2.5V/3.3V LVPECL/ECL FANOUT BUFFER

ICS853111B
LOW SKEW, 1-TO-10, DIFFERENTIAL-TO-2.5V, 3.3V LVPECL/ECL FANOUT BUFFER
SCHEMATIC EXAMPLE
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.
VC C
Zo = 50
Zo = 50
+
-
R2
R1
50
50
VCC
C6 (Option)
R3
0.1u
50
Zo = 50 Ohm
Zo = 50 Ohm
3.3V LVPECL
R9
50
C8 (Option)
0.1u
R4
1K
R10
50
R11
50
1
2
3
4
5
6
7
8
VCC
C LK_SEL
PCLK0
nPCLK0
VBB
PCLK1
nPCLK1
VEE
VCC
VCC=3.3V
(U1-9)
(U1-16)
VCC
(U1-25) (U1-32) (U1-1)
C1
0.1uF
C2
0.1uF
C3
0.1uF
C4
0.1uF
C5
0.1uF
Q3
nQ3
Q4
nQ4
Q5
nQ5
Q6
nQ6
24
23
22
21
20
19
18
17
U1
ICS853111
Zo = 50
Zo = 50
+
-
R8
R7
50
50
C7 (Option)
0.1u
R13
50
FIGURE 6. EXAMPLE ICS853111B LVPECL CLOCK OUTPUT BUFFER SCHEMATIC
THERMAL RELEASE PATH
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 M ASK
SIGNAL
TRACE
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.
EXPOSED PAD
SOLDER
SIGNAL
TRACE
GROUND PLANE
THERMAL VIA
Expose Metal Pad
(GROUND PAD)
FIGURE 7. P.C. BOARD FOR EXPOSED PAD THERMAL RELEASE PATH EXAMPLE
IDT^™ / ICS^™ 1-TO-10, LVPECL/ECL FANOUT BUFFER
12
ICS853111BY REV. B SEPTEMBER 5, 2007