Si595
R
EVISION
D
V
O L TAG E
- C
ONTR OLLED
C
RYSTAL
O
S C I L L A T O R
(VCXO)
10
TO
525 MH
Z
Features
Available with any-rate output
frequencies from 10 to 525 MHz
3rd generation DSPLL
®
with
superior jitter performance
Internal fixed fundamental mode
crystal frequency ensures high
reliability and low aging
Available CMOS, LVPECL,
LVDS, and CML outputs
3.3, 2.5, and 1.8 V supply options
Industry-standard 5 x 7 mm
package and pinout
Pb-free/RoHS-compliant
–40 to +85 ºC operating range
Si5602
Applications
Ordering Information:
SONET/SDH (OC-3/12/48)
Networking
SD/HD SDI/3G SDI video
FTTx
Clock recovery and jitter cleanup PLLs
FPGA/ASIC clock generation
See page 7.
Description
The Si595 VCXO utilizes Silicon Laboratories’ advanced DSPLL
®
circuitry to
provide a low-jitter clock at high frequencies. The Si595 is available with
any-rate output frequency from 10 to 525 MHz. Unlike traditional VCXOs,
where a different crystal is required for each output frequency, the Si595
uses one fixed crystal to provide a wide range of output frequencies. This IC-
based approach allows the crystal resonator to provide exceptional
frequency stability and reliability. In addition, DSPLL clock synthesis
provides supply noise rejection, simplifying the task of generating low-jitter
clocks in noisy environments. The Si595 IC-based VCXO is factory-
configurable for a wide variety of user specifications including frequency,
supply voltage, output format, tuning slope, and absolute pull range (APR).
Specific configurations are factory programmed at time of shipment, thereby
eliminating the long lead times associated with custom oscillators.
Pin Assignments:
See page 6.
(Top View)
V
C
1
6
V
DD
OE
2
5
CLK–
GND
3
4
CLK+
Functional Block Diagram
V
DD
CLK–
CLK+
Fixed
Frequency
XO
Any-rate
10–525 MHz
DSPLL
®
Clock Synthesis
ADC
Vc
OE
GND
Preliminary Rev. 0.2 8/09
Copyright © 2009 by Silicon Laboratories
Si595
Si595
1. Electrical Specifications
Table 1. Recommended Operating Conditions
Parameter
Supply Voltage
1
Symbol
V
DD
Test Condition
3.3 V option
2.5 V option
1.8 V option
Supply Current
I
DD
Output enabled
LVPECL
CML
LVDS
CMOS
Tristate mode
Output Enable (OE)
2
Operating Temperature Range
T
A
V
IH
V
IL
Min
2.97
2.25
1.71
—
—
—
—
—
0.75 x V
DD
—
–40
Typ
3.3
2.5
1.8
120
110
100
90
60
—
—
—
Max
3.63
2.75
1.89
135
120
110
100
75
—
0.5
85
V
°C
V
Units
mA
Notes:
1.
Selectable parameter specified by part number. See 3. "Ordering Information" on page 7 for further details.
2.
OE pin includes an internal 17 k pullup resistor to V
DD
for output enable active high or a 17 k pull-down resistor to
GND for output enable active low. See 3. "Ordering Information" on page 7.
Table 2. V
C
Control Voltage Input
Parameter
Control Voltage Tuning Slope
1,2,3
Symbol
K
V
Test Condition
10 to 90% of V
DD
Min
—
Typ
45
95
125
185
380
±1
±5
10.0
—
50
V
DD
/2
Max
—
Units
ppm/V
Control Voltage Linearity
4
Modulation Bandwidth
V
C
Input Impedance
V
C
Input Capacitance
Nominal Control Voltage
Control Voltage Tuning Range
L
VC
BW
Z
VC
C
VC
V
CNOM
V
C
BSL
Incremental
–5
–10
9.3
500
—
+5
+10
10.7
—
—
—
V
DD
%
kHz
k
pF
V
V
@ f
O
—
0
Notes:
1.
Positive slope; selectable option by part number. See 3. "Ordering Information" on page 7.
2.
For best jitter and phase noise performance, always choose the smallest K
V
that meets the application’s minimum APR
requirements. See “AN266: VCXO Tuning Slope (K
V
), Stability, and Absolute Pull Range (APR)” for more information.
3.
K
V
variation is ±10% of typical values.
4.
BSL determined from deviation from best straight line fit with V
C
ranging from 10 to 90% of V
DD
. Incremental slope
determined with V
C
ranging from 10 to 90% of V
DD
.
2
Preliminary Rev. 0.2
Si595
Table 3. CLK± Output Frequency Characteristics
Parameter
Nominal Frequency
1,2,3
Temperature Stability
1,4
Absolute Pull Range
1,4
Power up Time
5
APR
t
OSC
Symbol
f
O
Test Condition
LVDS/CML/LVPECL
CMOS
T
A
= –40 to +85 ºC
V
DD
= 3.3 V
Min
10
10
–20
–50
±15
—
Typ
—
—
—
—
—
—
Max
525
160
+20
+50
±370
10
Units
MHz
ppm
ppm
ms
Notes:
1.
See Section 3. "Ordering Information" on page 7 for further details.
2.
Specified at time of order by part number.
3.
Nominal output frequency set by V
CNOM
= V
DD
/2.
4.
Selectable parameter specified by part number.
5.
Time from power up or tristate mode to f
O
.
Table 4. CLK± Output Levels and Symmetry
Parameter
LVPECL Output Option
1
Symbol
V
O
V
OD
V
SE
Test Condition
mid-level
swing (diff)
swing (single-ended)
mid-level
swing (diff)
Min
V
DD
– 1.42
1.1
0.55
1.125
0.5
Typ
—
Max
V
DD
– 1.25
1.9
0.95
1.275
0.9
Units
V
V
PP
V
PP
V
V
PP
—
—
1.20
0.7
LVDS Output Option
2
V
O
V
OD
CML Output Option
2
CMOS Output Option
3
Rise/Fall time (20/80%)
Symmetry (duty cycle)
V
O
V
OD
V
OH
V
OL
t
R,
t
F
mid-level
swing
(diff)
—
0.70
0.8 x V
DD
V
DD
– 0.75
0.95
—
—
—
2
—
—
1.20
V
DD
V
V
PP
V
—
LVPECL/LVDS/CML
CMOS with C
L
= 15 pF
LVPECL:
LVDS:
CMOS:
V
DD
– 1.3 V (diff)
1.25 V (diff)
V
DD
/2
—
—
45
0.4
350
—
55
ps
ns
%
SYM
Notes:
1.
50
to V
DD
– 2.0 V.
2.
R
term
= 100
(differential).
3.
C
L
= 15 pF. Sinking or sourcing 12 mA for V
DD
= 3.3 V, 6 mA for V
DD
= 2.5 V, 3 mA for V
DD
= 1.8 V.
Preliminary Rev. 0.2
3
Si595
Table 5. CLK± Output Phase Jitter
Parameter
Phase Jitter (RMS)
1,2
for F
OUT
of 50 MHz < F
OUT
525 MHz
Symbol
Test Condition
Kv = 45 ppm/V
12 kHz to 20 MHz
Kv = 95 ppm/V
12 kHz to 20 MHz
Kv = 125 ppm/V
12 kHz to 20 MHz
Kv = 185 ppm/V
12 kHz to 20 MHz
Kv = 380 ppm/V
12 kHz to 20 MHz
Min
—
—
—
—
—
Typ
0.5
0.5
0.5
0.5
0.7
Max
—
—
—
—
—
Units
ps
J
Notes:
1.
Differential Modes: LVPECL/LVDS/CML. Refer to AN256 and AN266 for further information.
2.
For best jitter and phase noise performance, always choose the smallest K
V
that meets the application’s minimum APR
requirements. See “AN266: VCXO Tuning Slope (K
V
), Stability, and Absolute Pull Range (APR)” for more information.
Table 6. CLK± Output Period Jitter
Parameter
Period Jitter*
Symbol
J
PER
Test Condition
RMS
Peak-to-Peak
Min
—
—
Typ
3
35
Max
—
—
Units
ps
*Note:
Any output mode, including CMOS, LVPECL, LVDS, CML. N = 1000 cycles. Refer to AN279 for further information.
Table 7. CLK± Output Phase Noise (Typical)
Offset Frequency
74.25 MHz
185 ppm/V
LVPECL
100 Hz
1 kHz
10 kHz
100 kHz
1 MHz
10 MHz
20 MHz
–77
–101
–121
–134
–149
–151
–150
148.5 MHz
185 ppm/V
LVPECL
–68
–95
–116
–128
–144
–147
–148
155.52 MHz
95 ppm/V
LVPECL
–77
–101
–119
–127
–144
–147
–148
Units
dBc/Hz
Table 8. Absolute Maximum Ratings
1
Parameter
Maximum Operating Temperature
Supply Voltage
Symbol
T
AMAX
V
DD
Rating
85
–0.5 to +3.8
Units
ºC
V
4
Preliminary Rev. 0.2
Si595
Table 8. Absolute Maximum Ratings
1
Parameter
Input Voltage
Storage Temperature
ESD Sensitivity (HBM, per JESD22-A114)
Soldering Temperature (Pb-free profile)
2
Soldering Temperature Time @ T
PEAK
(Pb-free profile)
2
Symbol
V
I
T
S
ESD
T
PEAK
t
P
Rating
–0.5 to V
DD
+ 0.3
–55 to +125
2500
260
20–40
Units
Volts
ºC
Volts
ºC
seconds
Notes:
1.
Stresses beyond those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional
operation or specification compliance is not implied at these conditions. Exposure to maximum rating conditions for
extended periods may affect device reliability.
2.
The device is compliant with JEDEC J-STD-020C. Refer to Si5xx Packaging FAQ available for download from
www.silabs.com/VCXO
for further information, including soldering profiles.
Table 9. Environmental Compliance
The Si595 meets the following qualification test requirements.
Parameter
Mechanical Shock
Mechanical Vibration
Solderability
Gross & Fine Leak
Resistance to Solvents
Conditions/Test Method
MIL-STD-883G, Method 2002.3 B
MIL-STD-883G, Method 2007.3 A
MIL-STD-883G, Method 203.8
MIL-STD-883G, Method 1014.7
MIL-STD-883G, Method 2015
Preliminary Rev. 0.2
5