Si5020-EVB - Silicon Labs

Si 5 0 2 0 - EVB
EVALUATION BOARD FOR Si5020 SiPHY™ MULTI-RATE
S O N E T / S D H C L O C K A N D D A TA R E C O V E R Y I C
Description
Features
The Si5020 evaluation board provides a platform for
testing and characterizing Silicon Laboratories’ Si5020
SiPHY™ multi-rate SONET/SDH clock and data
recovery IC. The Si5020 CDR supports OC-48/12/3,
STM-16/4/1, Gigabit Ethernet, and 2.7 Gbps FEC rates.
„
Single 2.5 V power supply
Differential I/Os ac coupled
„ Simple jumper configuration
„
All high-speed I/Os are AC coupled to ease interfacing
to industry standard test equipment.
Function Block Diagram
Jitter
Analyzer
Pulse
Generator
ZC = 50 Ω
ZC = 50 Ω
+
REFCLK
–
+
CLKOUT
–
ZC = 50 Ω
ZC = 50 Ω
Si5020
Pattern
Generator
ZC = 50 Ω
ZC = 50 Ω
+
DATAIN
–
RATESEL0
RATESEL1
PWRDN/CAL
Scope
+
DATAOUT
–
ZC = 50 Ω
ZC = 50 Ω
Pattern
Analyzer
LOL
REXT
10 kΩ
Jumpers
Test
Point
Si5020-EVB
Rev C
Rev. 1.0 12/02
Copyright © 2002 by Silicon Laboratories
Si5020-EVB-10
Si5020-EVB
Functional Description
The evaluation board simplifies characterization of the
Si5020 Clock and Data Recovery (CDR) device by
providing access to all of the Si5020 I/Os. Device
performance can be evaluated by following the Test
Configuration section below. Specific performance
metrics include jitter tolerance, jitter generation, and
jitter transfer.
Power Supply
The evaluation board requires one 2.5 V supply. Supply
filtering is placed on the board to filter typical system
noise components, however, initial performance testing
should use a linear supply capable of supplying 2.5 V
±5% dc.
CAUTION: The evaluation board is designed so that the
body of the SMA jacks and GND are shorted. Care must
be taken when powering the PCB at potentials other
than GND at 0.0 V and VDD at 2.5 V relative to chassis
GND.
To improve the DATAOUT eye-diagram, short 100 Ω
transmission line segments precede the 50 Ω highspeed traces. These segments increase the interface
bandwidth from the chip to the 50 Ω traces and reduce
data inter-symbol-interference. Please refer to Silicon
Laboratories application note AN43 for more details.
Note: The 50 Ω termination is for each terminal/side of a differential signal, thus the differential termination is actually 50 Ω + 50 Ω = 100 Ω.
REFCLK
REFCLK is used to center the frequency of the
DSPLL™ so that the device can lock to the data. Ideally
the REFCLK frequency should be 1/128th, 1/32nd, or
1/16th the VCO frequency and must have a frequency
accuracy of ±100 PPM. Internally, the CDR
automatically recognizes the REFCLK frequency within
one of these three frequency ranges. Typical REFCLK
frequencies are given in Table 1. REFCLK is AC
coupled to the SMA jacks located on the top side of the
evaluation board.
Self-Calibration
The Si5020 device provides an internal self-calibration
function that optimizes the loop gain parameters within
the internal DSPLLTM. Self-calibration is initiated by a
high-to-low transition of the PWRDN/CAL signal while a
valid reference clock is supplied to the REFCLK input.
On the Si5020-EVB board, a voltage detector IC is
utilized to initiate self-calibration. The voltage detector
drives the PWRDN/CAL signal low after the supply
voltage has reached a specific voltage level. This circuit
is described in Silicon Laboratories application note
AN42. On the Si5020-EVB, the PWRDN/CAL signal is
also accessible via a jumper located in the lower lefthand corner of the evaluation board. PWRDN/CAL is
wired to the signal post adjacent to the 2.5 V post.
Device Powerdown
The CDR can be powered down via the PWRDN/CAL
signal. When asserted the evaluation board will draw
minimal current. PWRDN/CAL is controlled via one
jumper located in the lower left-hand corner of the
evaluation board. PWRDN/CAL is wired to the signal
post adjacent to the 2.5 V post.
CLKOUT, DATAOUT, DATAIN
These high-speed I/Os are wired to the board perimeter
on 30 mil (0.030 inch) 50 Ω microstrip lines to the endlaunch SMA jacks as labeled on the PCB. These I/Os
are AC coupled to simplify direct connection to a wide
array of standard test hardware. Because each of these
signals are differential both the positive (+) and negative
(–) terminals must be terminated to 50 Ω. Terminating
only one side will adversely degrade the performance of
the CDR. The inputs are terminated on the die with 50 Ω
resistors.
2
Table 1. Typical REFCLK Frequencies
SONET/SDH
Gigabit
Ethernet
SONET/
SDH with
Ratio of
15/14 FEC
REFCLK
VCO to
19.44 MHz
19.53 MHz
20.83 MHz
128
77.76 MHz
78.125 MHz
83.31 MHz
32
155.52 MHz
156.25 MHz
166.63 MHz
16
RATESEL
RATESEL is used to configure the CDR to recover clock
and data at different data rates. RATESEL is a two bit
binary input that is controlled via two jumpers located in
the lower left-hand corner of the evaluation board.
RATESEL0/1 are wired to the center posts (signal post)
between 2.5 V and GND. For example, the OC-48 data
rate is selected by jumping RATESEL0 to 0.0 V and
RATESEL1 to 0.0 V.
The table given on the evaluation board lists
approximate data rates for the jumper configurations
shown in Figure 1. Applications with data rates within
±7% of the given data rate are also accommodated.
Rev. 1.0
RATESEL1
RATESEL1
RATESEL0
RATESEL0
PWRDN/
CAL
PWRDN/
CAL
GND
2.5 V
1244 Mbps
2.5 V
GND
2488 Mbps
Jitter Generation: Referring to Figure 2, this test
requires a pattern generator, a clock source
(synthesizer signal source), a jitter analyzer, and a
pulse generator (all unconnected high-speed outputs
must be terminated to 50 Ω). During this test, there is no
modulation of the Data Clock, so the data that is sent to
the CDR is jitter free. The Jitter Analyzer measures the
RMS and peak-to-peak jitter on the CDR CLKOUT.
Thus, any jitter measured is jitter generated by the
CDR.
2.5 V
GND
2.5 V
GND
Si5020-EVB
RATESEL1
RATESEL1
RATESEL0
RATESEL0
PWRDN/
CAL
PWRDN/
CAL
622 Mbps
155 Mbps
Figure 1. RATESEL Jumper Configurations
Loss-of-Lock (LOL)
LOL is an indicator of the relative frequency between
the data and the REFCLK. LOL will assert when the
frequency difference is greater than ±600 PPM. In order
to prevent LOL from de-asserting prematurely, there is
hysterisis in returning from the out-of-lock condition.
LOL will be de-asserted when the frequency difference
is less than ±300 PPM.
Jitter Transfer: Referring to Figure 2, this test requires
a pattern generator, a clock source (synthesizer signal
source), a modulation source, a jitter analyzer, and a
pulse generator (all unconnected high-speed outputs
must be terminated to 50 Ω). During this test the Jitter
Analyzer modulates the data pattern and data clock
reference. The modulated data clock reference is
compared with the CLKOUT of the CDR. Jitter on
CLKOUT relative to the jitter on the data clock reference
is plotted versus modulation frequency at predefined
jitter amplitudes.
LOL is wired to a test point which is located on the
upper right-hand side of the evaluation board.
Test Configuration
The three critical tests that are typically performed on a
CDR device are jitter transfer, jitter tolerance, and jitter
generation. By connecting the Si5020 Evaluation Board
as shown in Figure 2, all three measurements can be
easily made.
REFCLK should be within ±100 PPM of the frequency
selected from Table 1. RATESEL must be configured to
match the desired data rate, and PWRDN/CAL must be
unjumpered.
Jitter Tolerance: Referring to Figure 2, this test
requires a pattern generator, a clock source
(synthesizer signal source), a modulation source, a jitter
analyzer, a pattern analyzer, and a pulse generator (all
unconnected high-speed outputs must be terminated to
50 Ω). During this test the Jitter Analyzer causes a
modulation on the data pattern which drives the DATAIN
ports of the CDR. The Bit-Error-Rate (BER) is monitored
on the Pattern Analyzer. The modulation (jitter)
frequency and amplitude is recorded when the BER
approaches a specified threshold.
Rev. 1.0
3
Si5020-EVB
Pulse
Generator
Scope
DATAOUT–
Pattern
Analyzer
GPIB
2.5 V
+ –
REFCLK+
REFCLK–
DATAIN+
DATAIN–
Pattern
Generator
+
REFCLK
–
+
DATAIN
–
DATAOUT
+
–
CLKOUT
+
–
Si5020-EVB
DATAOUT+
CLKOUT+
CLKOUT–
Jitter
Analyzer
Data Clock+
GPIB
GPIB
Clock
Synthesizer
Signal Source
FM
Modulation
Source
GPIB
Figure 2. Test Configuration for Jitter Tolerance, Transfer, and Generation
4
Rev. 1.0
VDD
2.5V
VDD
JP4
JP3
JP2
JP1
VDD
L1
VDD
J9
1206 BLM31A601S
POS1
POS2
1
C13
0603 100pF
C15
0603 100pF
C16
0603 100pF
C12
tantalum 10uF
2
VDD
MKDSN 2,5/3-5,08
C9
0805 Do Not Install
OUT
R2
VDD
2
MAX6376XR23-T
0603 2.5k
SIG
2
1
BODY
J8
JC 142-0701-801
SIG
2
0603 0.1uF
C6
20
19
15
0603 0.1uF
9
10
4
5
2
SIG
DOUT-
DIN-
DOUT+
REFCLK+
CLKOUT-
REFCLK-
CLKOUT+
3
8
18
C7
1
BODY
REXT
0603 0.1uF
0603 0.1uF
12
JC 142-0701-801
Figure 3. Si5020 Schematic
SIG
JC 142-0701-801
0603 0.1uF
13
16
17
J5
BODY
1
0603 0.1uF
JC 142-0701-801
BODY
1
2
SIG
J6
0603 0.1uF
C1
R1
0603 10k
2
BODY
C2
Si5020
JC 142-0701-801
J4
0603 0.1uF
2
SIG
JC 142-0701-801
5
Si5020-EVB
JC 142-0701-801
SIG
1
1
BODY
J2
6
C3
DIN+
C8
SIG
LOL
1
JC 142-0701-801
2
RATESEL1
RATESEL0
PWRDN/CAL
2
BODY
1
1
BODY
J1
J3
C4
GNDA
GNDB
GNDC
Rev. 1.0
C5
J7
U5
VDDA
VDDB
VDDC
VDDD
2
7
11
14
1
GND
V?
VCC
3
U4
Si5020-EVB
Bill of Materials
Si5020EVB Assy Rev B-02 BOM
Reference
C1,C2,C3,C4,C5,
C6,C7,C8
C12
C13,C15,C16
JP1,JP4
JP2,JP3
J1,J2,J3,J4,J5,J6,
J7,J8
J9
L1
R1
R2
U4
U5
PCB
No Load
C9
6
Part Desc
Part Number
Manufacturer
CAP, SM, 0.1uF, 0603
CAP, SM, 10 uF, TANTALUM, 3216
CAP, SM, 100 pF, 16V, 0603
CONNECTOR, HEADER, 2X1
CONNECTOR, HEADER, 3X1
C0603X7R160-104KNE
TA010TCM106KAR
C0603C0G500101KNE
2340-6111TN or 2380-6121TN
2340-6111TN or 2380-6121TN
Venkel
Venkel
Venkel
3M
3M
CONNECTOR, SMA, SIDE MOUNT
CONNECTOR, POWER, 2 POS
RESISTOR, SM, 0 OHM, 1206
RESISTOR, SM, 10K, 1%, 0603
RESISTOR, SM, 2.55K, 1%, 0603
MAX6376XR23-T
Si5020
PRINTED CIRCUIT BOARD
901-10003
1729018
CR1206-8W-000T
CR0603-16W-1002FT
CR0603-16W-2551FT
MAX6376XR23-T
SI5020-BM
Si5020-EVB PCB Rev C
SPARE,0805
Rev. 1.0
Amphenol
Phoenix Contact
Venkel
Venkel
Venkel
Maxim
Silicon Laboratories
Silicon Laboratories
Si5020-EVB
Figure 4. Si5020 Silkscreen
Rev. 1.0
7
Si5020-EVB
Figure 5. Si5020 Component Side
8
Rev. 1.0
Si5020-EVB
Figure 6. Si5020 Solder Side
Rev. 1.0
9
Si5020-EVB
Document Change List
Revision 0.41 to Revision 1.0
„
“Preliminary” language removed.
Evaluation Board Assembly Revision History
10
Assembly Level
PCB
Si5020 Device
Assembly Notes
A-01
A
A
Assemble per BOM rev A-01.
B-01
B
B
Assemble per BOM rev B-01.
B-02
C
B
Assemble per BOM rev B-02.
Rev. 1.0
Si5020-EVB
Notes:
Rev. 1.0
11
Si5020-EVB
Contact Information
Silicon Laboratories Inc.
4635 Boston Lane
Austin, TX 78735
Tel: 1+(512) 416-8500
Fax: 1+(512) 416-9669
Toll Free: 1+(877) 444-3032
Email: [email protected]
Internet: www.silabs.com
The information in this document is believed to be accurate in all respects at the time of publication but is subject to change without notice.
Silicon Laboratories assumes no responsibility for errors and omissions, and disclaims responsibility for any consequences resulting from
the use of information included herein. Additionally, Silicon Laboratories assumes no responsibility for the functioning of undescribed features
or parameters. Silicon Laboratories reserves the right to make changes without further notice. Silicon Laboratories makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Silicon Laboratories assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. Silicon Laboratories products are not designed, intended, or authorized for use in applications intended to
support or sustain life, or for any other application in which the failure of the Silicon Laboratories product could create a situation where personal injury or death may occur. Should Buyer purchase or use Silicon Laboratories products for any such unintended or unauthorized application, Buyer shall indemnify and hold Silicon Laboratories harmless against all claims and damages.
Silicon Laboratories, Silicon Labs, and SiPHY are trademarks of Silicon Laboratories Inc.
Other products or brandnames mentioned herein are trademarks or registered trademarks of their respective holders.
12
Rev. 1.0