2. Semtech
  3. GS12141 IBIS-AMI
GS12141 IBIS-AMI

Semtech GS12141 IBIS-AMI User guide

  • Hello! I am an AI chatbot trained to assist you with the Semtech GS12141 IBIS-AMI User guide. I’ve already reviewed the document and can help you find the information you need or explain it in simple terms. Just ask your questions, and providing more details will help me assist you more effectively!
GS12141 IBIS-AMI Model
User Guide
1 of 15
Semtech
Proprietary & Confidential
GS12141
User Guide Rev.1
PDS-061032 December 2015
www.semtech.com
GS12141
User Guide Rev.1
PDS-061032 December 2015
2 of 15
Semtech
Proprietary & Confidential
www.semtech.com
Revision History
Contents
1. GS12141 IBIS-AMI Model ..............................................................................................................................3
1.1 GS12141 Receiver IBIS Model .........................................................................................................4
1.1.1 GS12141 Receiver IBIS Model.............................................................................................4
1.1.2 GS12141 Receiver AMI Model............................................................................................4
1.1.3 GS12141 Receiver Simulation Results.............................................................................5
1.1.4 GS12141 Receiver Package Model...................................................................................6
1.1.5 GS12141 Receiver IRL Test Bench.....................................................................................7
1.2 GS12141 Transmitter IBIS-AMI Model .........................................................................................8
1.2.1 GS12141 Analog Driver IBIS Model..................................................................................8
1.2.2 GS12141 Transmitter AMI Model......................................................................................9
1.2.3 GS12141 Transmitter Package Model.......................................................................... 14
Version ECO PCN Date Changes and/or Modifications
1 029025 — December 2015
Updated GS12141 IBIS-AMI Model
description. Added Section 1.1.2 and
Section 1.1.3.
0 027430 — August 2015 New document.
GS12141
User Guide Rev.1
PDS-061032 December 2015
3 of 15
Semtech
Proprietary & Confidential
www.semtech.com
Introduction
The GS12141 is a low-power, multi-rate, serial digital re-timing cable equalizer
supporting 12G UHD-SDI. It is designed to equalize and restore signals received over
75Ω coaxial cable, automatically recover the embedded clock from the digital video
signal and re-time the incoming data. The device supports SMPTE ST 2082-1 (12G
UHD-SDI), ST 2081-1 (6G UHD-SDI), ST 424 (3G-SDI), ST 292-1 (HD-SDI), and ST 259-C
(SD-SDI) signals and is optimized for performance at 11.88Gb/s. The device also
supports equalization of MADI at 125Mb/s. This document describes the contents,
features, and use of the GS12141 IBIS-AMI model. The model includes receiver IBIS
model and a transmitter trace driver model and facilitates simulation of the GS12141 in
EDA platforms compliant with IBIS 5.0.
1. GS12141 IBIS-AMI Model
The GS12141 IBIS-AMI model is comprised of transmitter (Tx) and receiver (Rx) models
as shown in Figure 1-1. The Tx model includes IBIS and AMI models and can be used in
both time-domain and statistical simulation modes. The Rx includes IBIS and AMI
models and can be used for simulation in time-domain/bit-by-bit mode. The model will
be updated based on correlated lab data once validation is complete.
The Rx IBIS model models the DC-termination of the GS12141 high-speed inputs and
the Rx AMI model includes a cable equalizer based on pre-tape-out simulation data and
is representative of device performance. The Tx model contains the trace driver with
swing and pre-emphasis controls. The input to the transmitter model is equivalent to
the signal after the GS12141 CDR. The Rx and Tx models need to be used in separate test
benches to optimize swing and pre-emphasis settings. Note that the clock and data
recovery (CDR) functionality of the GS12141 is not included in these models.
Figure 1-1: Receiver and Transmitter Testbenches using the GS12141 IBIS-AMI Model
Tx
Rx
Receiver Testbench
Transmitter Testbench
Rx
Tx
GS12141
Channel 2
Channel 1
GS12141
GS12141
User Guide Rev.1
PDS-061032 December 2015
4 of 15
Semtech
Proprietary & Confidential
www.semtech.com
1.1 GS12141 Receiver IBIS Model
The GS12141 Receiver IBIS model consists of three parts: (1) the Analog Termination IBIS
model, (2) the Receiver AMI model, and (3) the QFN package model. The block diagram
in Figure 1-2 shows the sequence of signal flow and the individual parts of the model.
The external S-parameter file for the QFN Package model extends the accuracy of the
package effects beyond what can be described by R, L and C components in the IBIS 5.0
standard. The external S-parameter data is processed as part of the channel by the EDA
platforms.
Figure 1-2: GS12141 Receiver IBIS Model
1.1.1 GS12141 Receiver IBIS Model
The GS12141 receiver IBIS model is extracted from device simulation results. The
receiver IBIS model contains the GS12141 Receiver input termination circuitry and is
used by the EDA platform to determine the time-domain impulse response for the
channel. The current revision of the IBIS model contains typical (Typ), maximum (Max),
and minimum (Min) corners which can be selected from the EDA user interface.
Note that the IBIS model only contains the DC termination impedance of the receiver.
Frequency dependent simulation (e.g. return loss) using the IBIS file is not accurate. It is
recommended to use GS12141_RX_Term.s2p S-parameter file instead of the IBIS file for
input return loss (IRL) simulations. See Section 1.1.5 for details on the return loss
simulation setup.
1.1.2 GS12141 Receiver AMI Model
The GS12141 Receiver AMI model includes an equalizer and slicers. Note that the
receiver AMI model is designed for the 12G and 6G data rates (11.88Gb/s and 5.94Gb/s
respectively) and should not be used for lower data rates. For simulation at 3G and lower
rates, IBIS-only simulation without the AMI model should be used. The AMI model does
not include automatic equalization. The equalization level is controlled by the
cable_length model specific parameter, which specifies the cable length (in meters) for
signal restoration.
The upstream transmitter launch swing is specified via the launch_swing model specific
parameter. Table 1-1 shows the value of the launch_swing parameter for different
launch swings.
Input
IBIS
Model
Package
Model
(S-parameters)
Algorithmic
Model
From Channel
Receiver IBIS-AMI Model
GS12141
User Guide Rev.1
PDS-061032 December 2015
5 of 15
Semtech
Proprietary & Confidential
www.semtech.com
Reducing the number of points per unit interval (UI) can increase simulation speed at
the cost of lower accuracy. This parameter can be set in "Advanced Convolution
Options" in ADS Channel simulations. Recommended values for this parameter are 32,
64 or 128 points. Please consult the EDA vendor for guidance on optimizing simulation
speed if not using Keysight ADS software.
1.1.3 GS12141 Receiver Simulation Results
The plots in Figure 1-3 illustrate the expected model output jitter for coaxial cable loss
based on Belden 1694A at the 12G data rate.
Table 1-1: Receiver AMI Model launch_swing Parameter
launch_swing
Input Launch Swing (V
ppd
)
0250
1300
2350
3400
4450
5500
6550
7600
8650
9700
10 750
11 800 (default)
12 850
13 900
14 950
15 1000
GS12141
User Guide Rev.1
PDS-061032 December 2015
6 of 15
Semtech
Proprietary & Confidential
www.semtech.com
Figure 1-3: GS12141 Rx Model Output Eye Diagram and Jitter vs. Cable Length
Note that the clock and data recovery (CDR) functionality of the GS12141 is not included
in the AMI model. To ensure that the CDR can recover the data, the signal at the Rx
model output should have less than 0.5UI jitter and more than 350mV
ppd
vertical eye
opening for BER of 10-12. The user should optimize the receiver output to maximize
vertical and horizontal eye opening as shown in Figure 1-4.
Figure 1-4: Example Optimized Eye Diagram at the Receiver Output with 1E-12 BER
Mask
1.1.4 GS12141 Receiver Package Model
The GS12141 receiver package model is provided as a 4-Port S-parameter file
(GS12141_RX_Pkg.s4p) in standard touchstone format from 0GHz to 30GHz. Figure 1-5
shows the S-parameter port mapping inside the package model.
0m (Jpp = 8.42ps) 10m (Jpp = 8.00ps) 20m (Jpp = 12.21ps) 30m (Jpp = 14.31ps)
40m (J
pp = 1.68ps) 50m (Jpp = 22.31ps) 60m (Jpp = 27.78ps) 70m (Jpp = 38.72ps)
GS12141
User Guide Rev.1
PDS-061032 December 2015
7 of 15
Semtech
Proprietary & Confidential
www.semtech.com
Figure 1-5: GS12141 Receiver Package S-Parameter Port Mapping
1.1.5 GS12141 Receiver IRL Test Bench
The GS12141_RX_Term.s2p S-parameter file included with the IBIS-AMI model is
intended for Input Return Loss simulations of the GS12141. Figure 1-6 shows the
schematic for the IRL test bench with areas in which cable, connector, component, and
trace models can be inserted highlighted. Sample results using the test bench are
shown in Figure 1-7.
Figure 1-6: GS12141 Receiver IRL Test Bench
Pin SideDie Side
Port 1 Port 2
Port 3 Port 4
SDI
SDI
GS12141
User Guide Rev.1
PDS-061032 December 2015
8 of 15
Semtech
Proprietary & Confidential
www.semtech.com
Figure 1-7: GS12141 Receiver IRL Test Bench Sample Results
1.2 GS12141 Transmitter IBIS-AMI Model
The GS12141 Transmitter IBIS-AMI model consists of three parts: (1) the Analog Driver
IBIS model, (2) the Transmitter AMI model, and (3) the QFN package model. The block
diagram in Figure 1-8 shows the sequence of the signal flow and the individual parts of
the model.
Figure 1-8: GS12141 Transmitter IBIS-AMI Model
1.2.1 GS12141 Analog Driver IBIS Model
The transmitter output IBIS model receives processed signal information from the
Transmitter AMI model and applies the analog characteristics of the GS12141 trace
driver. The IBIS model only contains the DC characteristics of the driver in the I-V tables
of the IBIS file. Frequency dependent simulation (e.g. return loss) using the IBIS file is not
accurate. The GS12141_TX_Term.s2p S-parameter file can be used for output return loss
(ORL) simulations.
5
10 15 20 250 30
-40
-30
-20
-10
-50
0
freq, GHz
dB(S(1,1))
Output
IBIS
Model
Package
Model
(S-parameter)
Algorithmic
Model
To Channel
Transmitter IBIS-AMI Model
GS12141
User Guide Rev.1
PDS-061032 December 2015
9 of 15
Semtech
Proprietary & Confidential
www.semtech.com
1.2.2 GS12141 Transmitter AMI Model
The GS12141 Transmitter AMI model provides programmable swing and pre-emphasis
controls adjusted by model specific parameters.
• output_swing: Sets the output swing level (amplitude) of the driver
Default setting: 44 (800mV
ppd
)
Valid range: 0-63
Increments swing by approximately 15mV/step from 0-1100mV
ppd
• output_pe_amp: Sets the amplitude of pre-emphasis pulse
Default setting: 0
Valid range: 0-63
• output_pe_width: Sets the width of pre-emphasis pulse
Default setting: 0
Valid range: 0-15 (Note: GS12141 device has a setting range of 0-31 for
additional optimization capability)
Note: The amount of pre-emphasis varies with the settings for both output_pe_amp
and output_pe_width, providing between 0dB and 10dB of pre-emphasis on the first
bit after a transition. It is recommended to vary both parameters to determine optimum
settings for each design. To help the user chose initial settings sample simulated eye
diagrams are provided in Figure 1-9 through Figure 1-18. All results were captured with
a data rate of 11.88Gb/s, PRBS15 pattern, output_swing = 21 (400mV
ppd
), and statistical
simulation mode.
Figure 1-9: S21 of 5” FR4 Stripline
2
4
6810
12 14
16 18 20
22
0
24
-50
-40
-30
-20
-10
-60
0
freq, GHz
dB(SDD21)
m2
m2
freq=
dB(SDD21)=-4.324
5.940GHz
GS12141
User Guide Rev.1
PDS-061032 December 2015
10 of 15
Semtech
Proprietary & Confidential
www.semtech.com
Figure 1-10: Eye Diagram and Metrics After 5" FR4 Stripline: output_pe_amp=6, output_pe_width=2
Figure 1-11: S21 of 10” FR4 Stripline
2
4
6810
12 14
16 18 20
22
0
24
-50
-40
-30
-20
-10
-60
0
freq, GHz
dB(SDD21)
m2
m2
freq=
dB(SDD21)=-8.312
5.940GHz
GS12141
User Guide Rev.1
PDS-061032 December 2015
11 of 15
Semtech
Proprietary & Confidential
www.semtech.com
Figure 1-12: Eye Diagram and Metrics After 10” FR4 Stripline: output_pe_amp=13, output_pe_width=4
Figure 1-13: S21 of 15” Stripline
2
4
6810
12 14
16 18 20
22
0
24
-60
-50
-40
-30
-20
-10
-70
0
freq, GHz
dB(SDD21)
m2
m2
freq=
dB(SDD21)=-12.716
5.940GHz
GS12141
User Guide Rev.1
PDS-061032 December 2015
12 of 15
Semtech
Proprietary & Confidential
www.semtech.com
Figure 1-14: Eye Diagram and Metrics After 15" FR4 Stripline: output_pe_amp=46, output_pe_amp=6
Figure 1-15: S21 of 20” FR4 Stripline
2
4
6810
12 14
16 18 20
22
0
24
-60
-50
-40
-30
-20
-10
-70
0
freq, GHz
dB(SDD21)
m2
m2
freq=
dB(SDD21)=-16.249
5.940GHz
GS12141
User Guide Rev.1
PDS-061032 December 2015
13 of 15
Semtech
Proprietary & Confidential
www.semtech.com
Figure 1-16: Eye Diagram and Metrics After 20" FR4 Stripline: output_pe_amp=54, output_pe_width=10
Figure 1-17: S21 of 25” FR4 Stripline
2
4
6810
12 14
16 18 20
22
0
24
-80
-70
-60
-50
-40
-30
-20
-10
-90
0
freq, GHz
dB(SDD21)
m2
m2
freq=
dB(SDD21)=-20.697
5.940GHz
GS12141
User Guide Rev.1
PDS-061032 December 2015
14 of 15
Semtech
Proprietary & Confidential
www.semtech.com
Figure 1-18: Eye Diagram and Metrics After 5" FR4 Stripline: output_pe_amp=62, output_pe_amp=15
1.2.3 GS12141 Transmitter Package Model
The GS12141 transmitter package model is provided as a 4-Port S-parameter file
(GS12141_TX_Pkg.s4p) in standard touchstone format from 0GHz to 30GHz. Figure 1-19
shows the S-parameter port mapping inside the package model. The same package
model is used for the SDO0/SDO0
and SDO1/SDO1 outputs.
Figure 1-19: GS12141 Transmitter Package S-Parameter Port Mapping
Pin SideDie Side
Port 1 Port 2
Port 3 Port 4
DDOx
DDOx
IMPORTANT NOTICE
Information relating to this product and the application or design described herein is believed to be reliable, however such information is
provided as a guide only and Semtech assumes no liability for any errors in this document, or for the application or design described herein.
Semtech reserves the right to make changes to the product or this document at any time without notice. Buyers should obtain the latest relevant
information before placing orders and should verify that such information is current and complete. Semtech warrants performance of its
products to the specifications applicable at the time of sale, and all sales are made in accordance with Semtech’s standard terms and conditions
of sale.
SEMTECH PRODUCTS ARE NOT DESIGNED, INTENDED, AUTHORIZED OR WARRANTED TO BE SUITABLE FOR USE IN LIFE-SUPPORT APPLICATIONS,
DEVICES OR SYSTEMS, OR IN NUCLEAR APPLICATIONS IN WHICH THE FAILURE COULD BE REASONABLY EXPECTED TO RESULT IN PERSONAL
INJURY, LOSS OF LIFE OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE. INCLUSION OF SEMTECH PRODUCTS IN SUCH APPLICATIONS IS
UNDERSTOOD TO BE UNDERTAKEN SOLELY AT THE CUSTOMER’S OWN RISK. Should a customer purchase or use Semtech products for any such
unauthorized application, the customer shall indemnify and hold Semtech and its officers, employees, subsidiaries, affiliates, and distributors
harmless against all claims, costs damages and attorney fees which could arise.
The Semtech name and logo are registered trademarks of the Semtech Corporation. All other trademarks and trade names mentioned may be
marks and names of Semtech or their respective companies. Semtech reserves the right to make changes to, or discontinue any products
described in this document without further notice. Semtech makes no warranty, representation or guarantee, express or implied, regarding the
suitability of its products for any particular purpose. All rights reserved.
© Semtech 2015
GS12141
User Guide Rev.1
PDS-061032 December 2015
15 of 15
Semtech
15Proprietary & Confidential
Contact Information
Semtech Corporation
200 Flynn Road, Camarillo, CA 93012
Phone: (805) 498-2111, Fax: (805) 498-3804
www.semtech.com
/