1 of 16
Proprietary & Confidential
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate Cable Driver
www.gennum.com
Features
• SMPTE 292M, SMPTE 344M and SMPTE 259M
compliant
• Dual coaxial cable driving outputs with selectable
slew rate
•50Ω differential PECL input
• Pb-free and RoHS compliant
• Seamless interface to other HD-LINX® II family
products
• Single 3.3V power supply operation
• Operating temperature range: 0°C to 70°C
Applications
• SMPTE 292M, SMPTE 344M and SMPTE 259M Coaxial
Cable Serial Digital Interfaces
Description
The GS1578A is a second generation high speed BiCMOS
integrated circuit designed to drive one or two 75Ω co-axial
cables.
The GS1578A may drive data rates up to 1.485Gb/s and
provides two selectable slew rates in order to achieve
compliance to SMPTE 259M, SMPTE 344M and SMPTE
292M.
The GS1578A accepts a LVPECL level differential input that
may be AC coupled. External biasing resistors at the inputs
are not required.
Power consumption is typically 168mW using a 3.3V
power supply. The GS1578A is Pb-free, and the
encapsulation compound does not contain halogenated
flame retardant.
This component and all homogeneous subcomponents are
RoHS compliant.
Figure A: GS1578A Functional Block Diagram
SDO
R
SET
SDO
SDI
SDI
SD/HD
BANDGAP REFERENCE AND BIASING CIRCUIT
OUTPUT STAGE &
CONTROL
INPUT
DIFFERENTIAL
PAIR
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
2 of 16
Proprietary & Confidential
Revision History
Contents
Features.................................................................................................................................................................1
Applications.........................................................................................................................................................1
Description...........................................................................................................................................................1
Revision History .................................................................................................................................................2
1. Pin Out...............................................................................................................................................................4
1.1 GS1578A Pin Assignment ..............................................................................................................4
1.2 GS1578A Pin Descriptions .............................................................................................................4
2. Electrical Characteristics ............................................................................................................................5
2.1 Absolute Maximum Ratings ..........................................................................................................5
2.2 DC Electrical Characteristics ........................................................................................................5
2.3 AC Electrical Characteristics ........................................................................................................6
3. Solder Reflow Profiles..................................................................................................................................7
4. Input / Output Circuits ................................................................................................................................8
5. Detailed Description.....................................................................................................................................9
5.1 Input Interfacing ...............................................................................................................................9
5.2 Output Interfacing ...........................................................................................................................9
5.3 Output Return Loss Measurement ........................................................................................... 11
5.4 Output Amplitude (RSET) ........................................................................................................... 12
6. Application Information .......................................................................................................................... 13
6.1 PCB Layout ....................................................................................................................................... 13
6.2 Typical Application Circuit ........................................................................................................ 13
7. Package and Ordering Information...................................................................................................... 14
Version ECR PCN Date Changes and/or Modifications
5 153754 – November 2009 Updated to latest Gennum template.
4 139637 38695 March 2006 Corrected pad standoff height and tolerances for pad width & package
dimension. Corrected pad shape.
3 139113 38124 January 2006 Corrected Input Differential Swing to 2200mV.
2 137885 – September 2005 Corrected process to BiCMOS. Updated eye diagrams in Section 5.2.
1 137132 – June 2005 Converted to Data Sheet. Changed title of Figure 3-2 to clarify that it is the
Pb reflow profile. Updated SD additive jitter number in the AC electrical
characteristics table to be typically 20psp-p. Updated dimensions on center
pad of the PCB footprint in Section 7.2 to match the dimensions of the
center pad of the device. Corrected part number in ordering information.
Rephrased the RoHS Compliant statement.
0 136045 – February 2005 Converted to Preliminary Data Sheet.
A 135502 – February 2005 New document.
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
3 of 16
Proprietary & Confidential
7.1 Package Dimensions ..................................................................................................................... 14
7.2 Recommended PCB Footprint ................................................................................................... 15
7.3 Packaging Data ............................................................................................................................... 15
7.4 Ordering Information ................................................................................................................... 16
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
4 of 16
Proprietary & Confidential
1. Pin Out
1.1 GS1578A Pin Assignment
Figure 1-1: 16-Pin QFN
1.2 GS1578A Pin Descriptions
GS1578A
(top view)
1
V
EE
SDI
SDI
2
3
4
SDO
SDO
VCC
12
11
10
9
57
68
NC
NC
NC
NC
13
14
15
16
Center Pad
(bottom of package)
NC
NC
NC
NC
RSET
SD / HD
Table 1-1: Pin Descriptions
Pin Number Name Timing Typ e Description
1,2 SDI, SDI Analog Input Serial digital differential input.
3V
EE – Power Most negative power supply connection. Connect to GND.
4R
SET Analog Input External output amplitude control resistor.
5,6,7,8,13,14,
15,16
NC – – No Connect. Not bonded internally.
9V
CC – Power Most positive power supply connection. Connect to +3.3V.
10 SD/HD Non
Synchronous
Input Output slew rate control. When set HIGH, the output will meet
SMPTE 259M rise/fall time specifications. When set LOW, the serial
outputs will meet SMPTE 292M rise/fall time specifications.
11,12 SDO, SDO Analog Output Serial digital differential output.
– Center Pad – Power Connect to most negative power supply plane following the
recommendations in Recommended PCB Footprint on page 15.
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
5 of 16
Proprietary & Confidential
2. Electrical Characteristics
2.1 Absolute Maximum Ratings
Table 2-1 lists the absolute maximum ratings for the GS1578A. Conditions exceeding the
limits listed may cause permanent damage to the device. This is a stress rating only and
functional operation of the device at these or any other conditions above those listed in
the operational sections of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
2.2 DC Electrical Characteristics
Table 2-2 shows the DC electrical characteristics of the GS1578A where conditions are
VDD = 3.3V ±5%, TA = 0°C to 70°C, unless otherwise shown.
Table 2-1: Absolute Maximum Ratings
Parameter Value
Supply Voltage -0.5V to +3.6 VDC
Input ESD Voltage 2kV
Storage Temperature Range -50°C < Ts < 125°C
Input Voltage Range (any input) -0.3 to (VCC +0.3)V
Operating Temperature Range 0°C to 70°C
Solder Reflow Temperature 260°C
Supply Voltage -0.5V to +3.6 VDC
Table 2-2: DC Electrical Characteristics
Parameter Symbol Conditions Min Typ Max Units
Supply Voltage VCC – 3.135 3.3 3.465 V
Power Consumption PDTA = 25°C – 168 – mW
Supply Current IsTA = 25°C – 51 64 mA
Output Voltage VCMOUT Common mode – VCC - VOUT –V
Input Voltage VCMIN Common mode 1.6 +
ΔVSDI/2
–V
CC -
ΔVSDI/2
V
SD/HD Input VIH –2.4––V
VIL –––0.8V
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
6 of 16
Proprietary & Confidential
2.3 AC Electrical Characteristics
Table 2-3 shows the AC electrical characteristics of the GS1578A where conditions are
VDD = 3.3V, TA = 0°C to 70°C, unless otherwise shown.
Table 2-3: AC Electrical Characteristics
Parameter Symbol Conditions Min Ty p Max Units Notes
Serial input data rate DRSDO – – – 1.485 Gb/s 1
Additive jitter – 1.485Gb/s – 22 – psp-p –
– 270Mb/s – 20 – psp-p –
Rise/Fall time tr, tfSD/HD=0 – – 220 ps 2
tr, tfSD/HD=1 400 – 800 ps 2
Mismatch in rise/fall time Utr, Utf–––30ps–
Duty cycle distortion – SD/HD=0 – – 30 ps –
– SD/HD=1 – – 100 ps –
Overshoot – SD/HD=0 – – 10 % –
– SD/HD=1 – – 8 % –
Output Return Loss ORL – 15 – – dB –
Output Voltage Swing VOUT Single Ended
into 75Ω
external load
RSET = 750Ω
750 800 850 mVp-p –
Input Voltage Swing UVSDI Differential 300 – 2000 mVp-p –
NOTES:
1. The input coupling capacitor must be set accordingly for lower data rates.
2. Rise/Fall time measured between 20% and 80%.
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
7 of 16
Proprietary & Confidential
3. Solder Reflow Profiles
The device is manufactured with Matte-Sn terminations and is compatible with both
standard eutectic and Pb-free solder reflow profiles. MSL qualification was performed
using the maximum Pb-free reflow profile shown in Figure 3-1.The recommended
standard Pb reflow profile is shown in Figure 3-2.
Figure 3-1: Maximum Pb-free Solder Reflow Profile (Preferred)
Figure 3-2: Standard Pb Reflow Profile (Pb-free package)
25°C
150°C
200°C
217°C
260°C
250°C
Time
Temperature
8 min. max
60-180 sec. max
60-150 sec.
20-40 sec.
3°C/sec max
6°C/sec max
25°C
100°C
150°C
183°C
230°C
220°C
Time
Temperature
6 min. max
120 sec. max
60-150 sec.
10-20 sec.
3°C/sec max
6°C/sec max
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
8 of 16
Proprietary & Confidential
4. Input / Output Circuits
Figure 4-1: Differential Input Stage (SDI/SDI)
Figure 4-2: Differential Output Stage (SDO/SDO)
Figure 4-3: Slew Rate Select Input Stage
V
CC
V
CC
SDI SDI
10k 10k
5k
10k
V
cc
I
REF
SDO SDO
SD/HD
VCC
On Chip
Reference
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
9 of 16
Proprietary & Confidential
5. Detailed Description
5.1 Input Interfacing
S
DI/SDI are high impedance differential inputs. The equivalent input circuit is shown in
Figure 4-1
.
Several conditions must be observed when interfacing to these inputs:
• The differential input signal amplitude must be between 300 and 2000mVp-p.
• The common mode voltage range must be as specified in the DC Electrical
Characteristics on page 5.
• For input trace lengths longer than approximately 1cm, the inputs should be
terminated as shown in the Typical Application Circuit.
The GS1578A inputs are self-biased, allowing for simple AC coupling to the device. For
serial digital video, a minimum capacitor value of 4.7μF should be used to allow
coupling of pathological test signals. A tantalum capacitor is recommended.
SD/HD Input Pin
The GS1578A SDO rise and fall times can be set to comply with both SMPTE 259M/344M
and SMPTE 292M. For all SMPTE 259M standards, or any data rate that requires longer
rise and fall time characteristics, the SD/HD pin must be set HIGH by the application
layer. For SMPTE 292M standards and signals which require faster rise and fall times,
this pin should be set LOW.
5.2 Output Interfacing
The GS1578A outputs are current mode, and will drive 800mV into a 75Ω load. These
outputs are protected from accidental static damage with internal static protection
diodes.
The SMPTE 292M, SMPTE 344M and SMPTE 259M standards require that the output of a
cable driver have a source impedance of 75Ω and a return loss of at least 15dB between
5MHz and 1.485GHz.
In order for an SDI output circuit using the GS1578A to meet this specification, the
output application circuit shown in Typical Application Circuit on page 13 is
recommended.
The value of L
COMP
will vary depending on the PCB layout, with a typical value of 5.6nH
.
A 4.7μF capacitor is used for AC coupling the output of the device. This value is chosen
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
10 of 16
Proprietary & Confidential
to ensure that pathological signals can be coupled without a significant DC component
occurring. Please see Application Information on page 13 for more details.
Figure 5-1: Output Signal for 270Mb/s Input
Figure 5-2: Output Signal for 1.485Gb/s Input
The output protection diodes act as a varactor (voltage controlled capacitor) as shown in
Figure 5-3. Therefore, when measuring return loss at the GS1578A output, it is necessary
to take the measurement for both a logic high and a logic low output condition.
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
11 of 16
Proprietary & Confidential
Consequently, the output capacitance of the device is dependent on the logic state of the
output.
Figure 5-3: Static Protection Diodes
5.3 Output Return Loss Measurement
To perform a practical return loss measurement, it is necessary to force the GS1578A
output to a DC high or low condition. The actual measured return loss will be based on
the outputs being static at VCC or VCC-1.6V. Under normal operating conditions the
outputs of the device swing between VCC-0.4V and VCC-1.2V, so the measured value of
return loss will not represent the actual operating return loss.
A simple method of calculating the values of actual operating return loss is to interpolate
the two return loss measurements. In this way, the values of return loss are estimated at
VCC-0.4V and VCC-1.2V based on the measurements at VCC and VCC-1.6V.
The two values of return loss (high and low) will typically differ by several decibels. If
the measured return loss is RH for logic high and RL for logic low, then the two values can
be interpolated as follows:
RIH = RH- (RH-RL)/4 and
RIL = RL+(RH-RL)/4
where RIH is the interpolated logic high value and RIL is the interpolated logic low value.
For example, if RH = -18dB and RL = -14dB, then the interpolated values are RIH = -17dB
and RIL = -15dB.
SDO
SDO
GS1578A
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
12 of 16
Proprietary & Confidential
5.4 Output Amplitude (RSET)
The output amplitude of the GS1578A is set to 800mVp-p with a tolerance of ±7% using
an RSET resistor of 750Ω. A ±1% SMT resistor should be used.
The RSET resistor is part of the high speed output circuit of the GS1578A. The resistor
should be placed as close as possible to the RSET pin. In addition, the PCB capacitance
should be minimized at this node by removing the PCB groundplane beneath the RSET
resistor and the RSET pin.
NOTE: Only an RSET value of 750Ω ±1% should be used. Using other values for RSET is not
recommended.
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
13 of 16
Proprietary & Confidential
6. Application Information
6.1 PCB Layout
Special attention must be paid to component layout when designing serial digital
interfaces for HDTV.
An FR-4 dielectric can be used, however, controlled impedance transmission lines are
required for PCB traces longer than approximately 1cm. Note the following PCB artwork
features used to optimize performance:
• The PCB trace width for HD rate signals is closely matched to SMT component
width to minimize reflections due to changes in trace impedance.
• The PCB groundplane is removed under the GS1578A output components to
minimize parasitic capacitance.
• The PCB ground plane is removed under the GS1578A RSET pin and resistor to
minimize parasitic capacitance.
• Input and output BNC connectors are surface mounted in-line to eliminate a
transmission line stub caused by a BNC mounting via high speed traces which are
curved to minimize impedance variations due to change of PCB trace width.
6.2 Typical Application Circuit
Figure 6-1: Typical Application Circuit
SD/HD
GS1578A
1
2
3
4
12
11
10
9
SDI
SDI
VEE
RSET
SDO
SDO
SD/HD
VCC
10n
75
5.6n
4u7
BNC
VCC
75
5.6n
10n 75
4u7
49.9
750
10n
49.9
4u7
75
BNC
VCC
4u7 VCC
* TYPICAL VALUE: VARIES WITH LAYOUT
DIFFERENTIAL
DATA INPUT
*
*
NOTE: All resistors in Ohms, capacitors in Farads,
and inductors in Henrys, unless otherwise noted.
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
14 of 16
Proprietary & Confidential
7. Package and Ordering Information
7.1 Package Dimensions
Figure 7-1: GS1578A Package Dimensions
DETAIL B
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
15 of 16
Proprietary & Confidential
7.2 Recommended PCB Footprint
The Center Pad should be connected to the most negative power supply plane (VEE) by
a minimum of 5 vias.
NOTE: Suggested dimensions only. Final dimensions should conform to customer
design rules and process optimizations.
7.3 Packaging Data
0.35
0.55
2.76
3.70
2.763.70
NOTE: All dimensions
are in millimeters.
0.65
CENTER PAD
Table 7-1: Packaging Data
Parameter Value
Package Type 4mm x 4mm 16-pin QFN
Package Drawing Reference JEDEC M0220
Moisture Sensitivity Level 3
Junction to Case Thermal Resistance, θj-c 31.0°C/W
Junction to Air Thermal Resistance, θj-a (at zero airflow) 43.8°C/W
Psi 11.0°C/W
Pb-free and RoHS compliant Yes
OTTAWA
232 Herzberg Road, Suite 101
Kanata, Ontario K2K 2A1
Canada
Phone: +1 (613) 270-0458
Fax: +1 (613) 270-0429
CALGARY
3553 - 31st St. N.W., Suite 210
Calgary, Alberta T2L 2K7
Canada
Phone: +1 (403) 284-2672
UNITED KINGDOM
North Building, Walden Court
Parsonage Lane,
Bishop’s Stortford Hertfordshire, CM23 5DB
United Kingdom
Phone: +44 1279 714170
Fax: +44 1279 714171
INDIA
#208(A), Nirmala Plaza,
Airport Road, Forest Park Square
Bhubaneswar 751009
India
Phone: +91 (674) 653-4815
Fax: +91 (674) 259-5733
SNOWBUSH IP - A DIVISION OF GENNUM
439 University Ave. Suite 1700
Toronto, Ontario M5G 1Y8
Canada
Phone: +1 (416) 925-5643
Fax: +1 (416) 925-0581
E-mail: sales@snowbush.com
Web Site: http://www.snowbush.com
MEXICO
288-A Paseo de Maravillas
Jesus Ma., Aguascalientes
Mexico 20900
Phone: +1 (416) 848-0328
JAPAN KK
Shinjuku Green Tower Building 27F
6-14-1, Nishi Shinjuku
Shinjuku-ku, Tokyo, 160-0023
Japan
Phone: +81 (03) 3349-5501
Fax: +81 (03) 3349-5505
E-mail: gennum-japan@gennum.com
Web Site: http://www.gennum.co.jp
TAI W A N
6F-4, No.51, Sec.2, Keelung Rd.
Sinyi District, Taipei City 11502
Taiwan R.O.C.
Phone: (886) 2-8732-8879
Fax: (886) 2-8732-8870
E-mail: gennum-taiwan@gennum.com
GERMANY
Hainbuchenstraße 2
80935 Muenchen (Munich), Germany
Phone: +49-89-35831696
Fax: +49-89-35804653
E-mail: gennum-germany@gennum.com
NORTH AMERICA WESTERN REGION
691 South Milpitas Blvd., Suite #200
Milpitas, CA 95035
United States
Phone: +1 (408) 934-1301
Fax: +1 (408) 934-1029
E-mail: naw_sales@gennum.com
NORTH AMERICA EASTERN REGION
4281 Harvester Road
Burlington, Ontario L7L 5M4
Canada
Phone: +1 (905) 632-2996
Fax: +1 (905) 632-2055
E-mail: nae_sales@gennum.com
KOREA
8F Jinnex Lakeview Bldg.
65-2, Bangidong, Songpagu
Seoul, Korea 138-828
Phone: +82-2-414-2991
Fax: +82-2-414-2998
E-mail: gennum-korea@gennum.com
DOCUMENT IDENTIFICATION
DATA SHEET
The product is in production. Gennum reserves the right to make changes to
the product at any time without notice to improve reliability, function or
design, in order to provide the best product possible.
GS1578A HD-LINX® II Multi-Rate Dual Slew-Rate
Cable Driver
Data Sheet
33657 - 5 November 2009
16 of 16
16
Proprietary & Confidential
Gennum Corporation assumes no liability for any errors or omissions in this document, or for the use of the circuits or devices described herein. The sale of
the circuit or device described herein does not imply any patent license, and Gennum makes no representation that the circuit or device is free from patent
infringement.
All other trademarks mentioned are the properties of their respective owners.
GENNUM and the Gennum logo are registered trademarks of Gennum Corporation.
© Copyright 2005 Gennum Corporation. All rights reserved.
www.gennum.com
GENNUM CORPORATE HEADQUARTERS
4281 Harvester Road, Burlington, Ontario L7L 5M4 Canada
Phone: +1 (905) 632-2996 Fax: +1 (905) 632-2055
E-mail: corporate@gennum.com www.gennum.com
CAUTION
ELECTROSTATIC SENSITIVE DEVICES
DO NOT OPEN PACKAGES OR HANDLE EXCEPT AT A
STATIC-FREE WORKSTATION
7.4 Ordering Information
Table 7-2: Ordering Information
Part Number Package Temperature Range
GS1578A GS1578ACNE3 16-pin QFN 0°C to 70°C