Si53302
1 : 1 0 L
OW
J
I T T E R
U
NIVERSAL
B
U FF E R
/L
EVEL
T
RANSLATOR WITH
2 : 1 I
NPUT
M
UX
Features
10 differential or 20 LVCMOS outputs
Ultra-low additive jitter: 45 fs rms
Wide frequency range: 1 to 725 MHz
Any-format input with pin selectable
output formats: LVPECL, Low Power
LVPECL, LVDS, CML, HCSL,
LVCMOS
2:1 clock input mux
Glitchless input clock switching
Synchronous output enable
Output clock division: /1, /2, /4
Independent V
DD
and V
DDO
:
1.8/2.5/3.3 V
1.2/1.5 V LVCMOS output support
Excellent power supply noise
rejection (PSRR)
Selectable LVCMOS drive strength to
tailor jitter and EMI performance
Loss of signal (LOS) monitors for
loss of input clock
Small size: 44-QFN (7 mm x 7 mm)
RoHS compliant, Pb-free
Industrial temperature range:
–40 to +85 °C
Ordering Information:
See page 29.
Applications
Pin Assignments
High-speed clock distribution
Ethernet switch/router
Optical Transport Network (OTN)
SONET/SDH
PCI Express Gen 1/2/3
Storage
Telecom
Industrial
Servers
Backplane clock distribution
Si53302
VDDOA
Q3
Q3
Q4
Q4
GND
Q5
Q5
Q6
Q6
VDDOB
36
35
34
44
43
42
41
40
39
38
37
Description
The Si53302 is an ultra low jitter ten output differential buffer with pin-selectable
output clock signal format and divider selection. The Si53302 features a 2:1 mux
with glitchless switching, making it ideal for redundant clocking applications. The
Si53302 utilizes Silicon Laboratories' advanced CMOS technology to fanout
clocks from 1 to 725 MHz with guaranteed low additive jitter, low skew, and low
propagation delay variability. The Si53302 features minimal cross-talk and
provides superior supply noise rejection, simplifying low jitter clock distribution in
noisy environments. Independent core and output bank supply pins provide
integrated level translation without the need for external circuitry.
DIVA
SFOUTA[1]
SFOUTA[0]
Q2
Q2
GND
Q1
Q1
Q0
Q0
NC
1
2
3
4
5
6
7
8
9
10
11
12
15
16
13
17
19
20
14
18
21
22
33
32
31
30
GND
PAD
29
28
27
26
25
24
23
DIVB
SFOUTB[1]
SFOUTB[0]
Q7
Q7
NC
Q8
Q8
Q9
Q9
CLK_SEL
Patents pending
Functional Block Diagram
VDD
Power
Supply
Filtering
Vref
LOS0
LOS1
CLK0
Vref
Generator
LOS
Monitor
DIV
A
VDDO
A
SFOUT
A
[1:0]
OE
A
Q0, Q1, Q2, Q3, Q4
DivA
/Q0, /Q1, /Q2, /Q3, /Q4
Bank A
DIV
B
VDDO
B
SFOUT
B
[1:0]
OE
B
Q5, Q6, Q7, Q8, Q9
Switching
Logic
DivB
CLK0
CLK1
CLK1
CLK_SEL
/Q5, /Q6, /Q7, /Q8, /Q9
Bank B
Rev. 1.1 9/14
Copyright © 2014 by Silicon Laboratories
VDD
LOS0
CLK0
CLK0
OEA
V
REF
OEB
CLK1
CLK1
LOS1
GND
Si53302
Si53302
T
ABLE O F
C
ONTENTS
Section
Page
1. Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
2. Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.1. Universal, Any-Format Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.2. Input Bias Resistors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2.3. Input Clock Voltage Reference (VREF) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2.4. Universal, Any-Format Output Buffer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.5. Glitchless Clock Input Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2.6. Synchronous Output Enable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2.7. Flexible Output Divider . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.8. Input Mux and Output Enable Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.9. Loss of Signal (LOS) Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.10. Power Supply (V
DD
and V
DDOX
) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.11. Output Clock Termination Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.12. AC Timing Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
2.13. Typical Phase Noise Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
2.14. Input Mux Noise Isolation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
2.15. Power Supply Noise Rejection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
3. Pin Description: 44-Pin QFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4. Ordering Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
5. Package Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
5.1. 7x7 mm 44-QFN Package Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
6. PCB Land Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
6.1. 7x7 mm 44-QFN Package Land Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
7. Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
7.1. Si53302 Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
7.2. Top Marking Explanation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Document Change List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
2
Rev. 1.1
Si53302
1. Electrical Specifications
Table 1. Recommended Operating Conditions
Parameter
Ambient Operating
Temperature
Supply Voltage Range*
Symbol
T
A
V
DD
LVDS, CML
Test Condition
Min
–40
1.71
2.38
2.97
LVPECL, low power LVPECL,
LVCMOS
HCSL
Output Buffer Supply
Voltage*
V
DDOX
LVDS, CML, LVCMOS
2.38
2.97
2.97
1.71
2.38
2.97
LVPECL, low power LVPECL
2.38
2.97
HCSL
2.97
Typ
—
1.8
2.5
3.3
2.5
3.3
3.3
1.8
2.5
3.3
2.5
3.3
3.3
Max
85
1.89
2.63
3.63
2.63
3.63
3.63
1.89
2.63
3.63
2.63
3.63
3.63
Unit
°C
V
V
V
V
V
V
V
V
V
V
V
V
*Note:
Core supply V
DD
and output buffer supplies V
DDO
are independent. LVCMOS clock input is not supported for
V
DD
=
1.8V but is supported for LVCMOS clock output for
V
DDOX
= 1.8V. LVCMOS outputs at 1.5V and 1.2V can be
supported via a simple resistor divider network. See “2.11.1. LVCMOS Output Termination To Support 1.5V and 1.2V”
Table 2. Input Clock Specifications
(V
DD
=1.8 V
5%, 2.5 V
5%, or 3.3 V
10%, T
A
=–40 to 85 °C)
Parameter
Differential Input Common
Mode Voltage
Differential Input Swing
(peak-to-peak)
LVCMOS Input High Volt-
age
LVCMOS Input Low Volt-
age
Input Capacitance
Symbol
V
CM
V
IN
V
IH
V
IL
C
IN
V
DD
= 2.5 V
5%, 3.3 V
10%
V
DD
= 2.5 V
5%, 3.3 V
10%
CLK0 and CLK1 pins with
respect to GND
Test Condition
V
DD
= 2.5 V
5%, 3.3 V
10%
Min
0.05
0.2
V
DD
x 0.7
—
—
Typ
—
—
—
—
5
Max
—
2.2
—
V
DD
x
0.3
—
Unit
V
V
V
V
pF
Rev. 1.1
3
Si53302
Table 3. DC Common Characteristics
(V
DD
= 1.8 V
5%,
2.5 V
5%, or 3.3 V
10%,T
A
= –40 to 85 °C)
Parameter
Supply Current
Output Buffer
Supply Current
(Per Clock Output)
@100 MHz (diff)
@200 MHz (CMOS)
Symbol
I
DD
I
DDOX
Test Condition
Min
—
Typ
65
35
35
20
30
35
5
8
15
VDD/2
—
0.5 x
VDD
—
—
—
25
25
Max
100
—
—
—
—
—
—
—
—
—
—
0.55 x
VDD
0.2 x
VDD
—
0.2xVDD
—
—
Unit
mA
mA
mA
mA
mA
mA
mA
mA
mA
V
V
V
V
V
V
k
k
LVPECL (3.3 V)
Low Power LVPECL (3.3 V)*
LVDS (3.3 V)
CML (3.3 V)
HCSL, 100 MHz, 2 pF load (3.3 V)
CMOS (1.8 V, SFOUT = Open/0),
per output, C
L
= 5 pF, 200 MHz
CMOS (2.5 V, SFOUT = Open/0),
per output, C
L
= 5 pF, 200 MHz
CMOS (3.3 V, SFOUT = 0/1),
per output, C
L
= 5 pF, 200 MHz
—
—
—
—
—
—
—
—
—
0.8 x
VDD
0.45 x
VDD
—
0.8xVDD
—
—
—
Input Clock Voltage
Reference
Input High Voltage
Input Mid Voltage
Input Low Voltage
Output Voltage High
(LOSx)
Output Voltage Low
(LOSx)
Internal Pull-down
Resistor
Internal Pull-up
Resistor
V
REF
V
IH
V
IM
V
IL
V
OH
V
OL
R
DOWN
R
UP
V
REF
pin
I
REF
= +/-500
A
SFOUTx, DIVx
CLK_SEL, OEx
SFOUTx, DIVx
3-level input pins
SFOUTx, DIVx
CLK_SEL, OEx
I
DD
= –1 mA
I
DD
= 1 mA
CLK_SEL, DIVx, SFOUTx
OEx, DIVx, SFOUTx
*Note:
Low-power LVPECL mode supports an output termination scheme that will reduce overall system power.
4
Rev. 1.1
Si53302
Table 4. Output Characteristics (LVPECL)
(V
DDOX
= 2.5 V ± 5%, or 3.3 V ± 10%,TA = –40 to 85 °C)
Parameter
Output DC Common Mode
Voltage
Single-Ended
Output Swing*
Symbol
V
COM
V
SE
Test Condition
Min
V
DDOX
– 1.595
0.55
Typ
—
0.80
Max
V
DDOX
– 1.245
1.050
Unit
V
V
*Note:
Unused outputs can be left floating. Do not short unused outputs to ground.
Table 5. Output Characteristics (Low Power LVPECL)
(V
DDOX
= 2.5 V ± 5%, or 3.3 V ± 10%,TA = –40 to 85 °C)
Parameter
Output DC Common
Mode Voltage
Single-Ended
Output Swing
Symbol
V
COM
V
SE
Test Condition
R
L
= 100
across
Qn and Qn
R
L
= 100
across
Qn and Qn
Min
V
DDOX
– 1.895
0.25
Typ
Max
V
DDOX
– 1.275
Unit
V
V
0.60
0.85
Table 6. Output Characteristics—CML
(V
DDOX
= 1.8 V
5%,
2.5 V
5%, or 3.3 V
10%,T
A
= –40 to 85 °C)
Parameter
Single-Ended Output
Swing
Symbol
V
SE
Test Condition
Terminated as shown in Figure 9
(CML termination).
Min
300
Typ
400
Max
550
Unit
mV
Table 7. Output Characteristics—LVDS
(V
DDOX
= 1.8 V
5%,
2.5 V
5%, or 3.3 V
10%,T
A
= –40 to 85 °C)
Parameter
Single-Ended Output
Swing
Output Common
Mode Voltage
(V
DDO
= 2.5 V or
3.3V)
Output Common
Mode Voltage
(V
DDO
= 1.8 V)
Symbol
V
SE
V
COM1
Test Condition
R
L
= 100
Ω
across Q
N
and Q
N
V
DDOX
= 2.38 to 2.63 V, 2.97 to
3.63 V, R
L
= 100
Ω
across Q
N
and Q
N
V
DDOX
= 1.71 to 1.89 V,
R
L
= 100
Ω
across Q
N
and Q
N
Min
247
1.10
Typ
—
1.25
Max
490
1.35
Unit
mV
V
V
COM2
0.85
0.97
1.25
V
Rev. 1.1
5