843034-06 Datasheet, PDF (16/24 Pages) Integrated Device Technology – FemtoClock™ Multi-Rate 3.3V LVPECL Frequency Synthesizer

843034-06 DATA SHEET
APPLICATION SCHEMATIC EXAMPLE
Figure 8 shows an example of 843034-06 application
schematic. In this example, the device is operated at
V =V = 3.3V. The device are be driven by a crystal,
CC
CCO
LVCMOS or LVPECL input sources. The 18pF parallel
resonant 25MHz crystal is used. The C1 = 27pF and C2 =
27pF are recommended for frequency accuracy. For different
3.3V
Zo = 50 Ohm
VCC
R1
133
R2
133
board layout, the C1 and C2 may be slightly adjusted for
optimizing frequency accuracy. For the LVPECL output
drivers, only two termination examples are shown in this
schematic. Additional termination approaches are shown in
the LVPECL Termination Application Note.
Zo = 50 Ohm
LVPECL
Dr iv er _LV PECL
R5
82.5
R6
82.5
U1
M8
VCC
C5
0.1u
OE_REF
OE_A
OE_B
VCC
NA0
NA1
NA2
1
2 ^M8
3 ^RESERVED
4
5
RESERVED
RESERVED
6 ^OE_REF
7 ^OE_A
8 ^OE_B
9 ^VCC
10 ^NA0
11 ^NA1
12 ^NA2
VEE
36
XTAL_OUT1 ₃₅
XTAL_IN1 ₃₄
XTAL_OUT0
XTAL_IN0
33
32
REF_CLK ₃₁
SEL1 ₃₀
SEL0 ₂₉
VCCA ₂₈
S_LOAD ₂₇
S_DATA ₂₆
S_CLOCK ₂₅
MR
Logic Control Input Examples
Set Logic
VCC
Input to
'1'
RU1
1K
To Logic
Input
pins
RD1
Not Install
Set Logic
VCC
Input to
'0'
RU2
Not Install
RD2
1K
To Logic
Input
pins
VCC
C6
0.1u
VCCO
C8
0.1u
VCCO
C7
0.1u
VCCO
C9
0.1u
25MHz X1
18pF
SEL1
SEL0
C1
27pF
C2
27pF
VCCA
C3
0.01u
FOUTA0
3.3V
R3
133
Zo = 50 Ohm
nFOUTA0
R9
C4
10u
VCC
VCC
10
V CC=3.3V
V CCO=3.3V
Zo = 50 Ohm
R7
82.5
R4
133
+
-
R8
82.5
MR
Zo = 50 Ohm
FOUTB0
+
Zo = 50 Ohm
nFOUTB0
-
R10
50
R11
50
Optional
R12
Y-Termination
50
REF_OUT
R13
33
Zo = 50 Ohm
LV CMOS
FIGURE 8. 843034-06 APPLICATION SCHEMATIC EXAMPLE
REVISION B 8/17/15
16
FemtoClock™ Multi-Rate 3.3V LVPECL Frequency Synthesizer