GS9028

GENLINX ™II GS9028 Cable Driver with Two Adjustable Outputs DATA SHEET FEATURES • SMPTE 259M compliant • two complementary outputs, adjustable from 50 to 1000mVp-p into 75Ω loads • operational from DC to 622Mb/s • nominal 470ps rise and fall times • < ±7% output amplitude control • 45% system power reduction over the GS9008 • no external pulldown resistors required • input hysteresis • operational down to 80mV input amplitude • operates from a single +5 or -5 volt supply • 8 pin SOIC • Pb-free and Green APPLICATIONS 4ƒsc, 4:2:2, and 4:4:4:4 serial digital video interfaces from 143Mb/s to 540Mb/s; general purpose high speed cable driver applications. ORDERING INFORMATION PART NUMBER GS9028-CKA GS9028-CTA GS9028-CKAE3 GS9028-CTAE3 PACKAGE 8 pin SOIC 8 pin SOIC Tape 8 pin SOIC 8 pin SOIC Tape TEMPERATURE 0°C to 70°C 0°C to 70°C 0°C to 70°C 0°C to 70°C Pb-FREE AND GREEN No No Yes Yes DESCRIPTION The GS9028 is a second generation bipolar integrated circuit designed to drive two 75Ω co-axial cables. GS9028 The GS9028 features two complementary outputs whose amplitude is controlled within ± 7%. The output signal levels are also adjustable from as low as 50mV to as high as 1000mV with little change in other performance parameters. The output amplitude of the output stage is varied by adjusting the RSET resistor value. The GS9028 consumes 45% less system power than the GS9008 and does not require external pulldown resistors resulting in a smaller PCB footprint. Operational with input amplitudes as low as 80mV, the GS9028 is a robust serial interface device. The GS9028 is packaged in an 8 pin SOIC and operates from a single +5 or -5 volt supply. BANDGAP REFERENCE AND BIASING CIRCUIT RSET SDI SDI INPUT DIFFERENTIAL PAIR WITH HYSTERESIS OUTPUT STAGE & RISE/FALL TIME CONTROL CIRCUIT SDO SDO BLOCK DIAGRAM Revision Date: June 2004 GENNUM CORPORATION P.O. Box 489, Stn. A, Burlington, Ontario, Canada L7R 3Y3 Tel. +1 (905) 632-2996 Fax. +1 (905) 632-5946 E-mail: info@gennum.com www.gennum.com Document No. 521 - 68 - 05 ABSOLUTE MAXIMUM RATINGS TA = 25°C unless otherwise specified PARAMETER Supply Voltage Input Voltage Range (any input) VALUE 5.5V -0.3 to (VCC +0.3)V 0 to 70°C -65 to 150°C 260°C GS9028 Operating Temperature Range Storage Temperature Lead Temperature (soldering, 10 sec) DC ELECTRICAL CHARACTERISTICS VCC = 5V, TA = 0°C to 70°C unless otherwise shown. Specifications assume 800mV output amplitude levels into end terminated 75Ω transmission lines. PARAMETER Supply Voltage System Power Consumption Supply Current Common Mode Input Voltage Range Differential Input Common Mode Output Voltage Range Differential Output Input Hysteresis SYMBOL VCC PD ΙS VCM,IN VDIFF VCM,OUT VOUT CONDITIONS MIN 4.75 TYP 5.00 165 MAX 5.25 195 UNITS V mW NOTES TEST LEVEL 1 3 Driving two 75Ω cables - 2.4+(VDIFF/2) 80 RSET = 59Ω 33 - 39 VCC-(VDIFF/2) 1000 - mA V 3 2 VCC-VOUT 800 - mV V 2 2 750 10 850 - mV mV 1 2 AC ELECTRICAL CHARACTERISTICS VCC = 5V, TA = 0°C to 70°C unless otherwise shown. Specifications assume 800mV output amplitude levels into end terminated 75Ω transmission lines. PARAMETER Serial Data Rate Additive Jitter SYMBOL CONDITIONS MIN 0 TYP 25 25 50 470 50 MAX 622 700 100 UNITS Mb/s ps p-p NOTES TEST LEVEL 1 270Mb/s 540Mb/s 622Mb/s 400 - 1 2 Output Rise/Fall Time Mismatch in Output Rise/Fall Times Overshoot Duty Cycle Distortion Output Return Loss TEST LEVELS 1. 100% tested at 25°C. 2. Guaranteed by design. 3. Correlated value. tR, tF 20% - 80% ps ps 3 1 540MHz NOTES - 5 50 17 8 100 - % ps dB 2 1 2 1. RMS additive jitter measured using Pseudo Random bit sequence (2 2. Measured with Gennum Evaluation Board (EB-RD35). 23 - 1). 2 of 7 521 - 68 - 05 PIN CONNECTIONS SDO SDO VEE RSET 8 VCC SDI SDI 1 2 7 GS9028 3 TOP VIEW 6 4 5 GS9028 VEE PIN DESCRIPTIONS NUMBER 1 2 4 6 7 SYMBOL SDO SDO RSET SDI SDI TYPE O O I I I Serial data output (inverse). Serial data output. Output amplitude control resistor. Serial data input (inverse). Serial data input. DESCRIPTION INPUT/OUTPUT CIRCUITS VCC SDO SDO SDI SDI + RSET Fig. 1 Input Circuit (pins 6 and 7) Fig. 2 Output Circuit (pins 1 and 2) 3 of 7 521 - 68 - 05 TYPICAL PERFORMACE CURVES (measured using the Typical Application Circuit) GS9028 Fig. 3 Output Eye Diagram 270Mb/s Fig. 4 Output Eye diagram 540Mb/s Fig. 5 Output Eye Diagram 622Mb/s 4 of 7 521 - 68 - 05 DETAILED DESCRIPTION INPUT INTERFACING SDI/SDI are high impedance differential inputs. Two conditions must be observed when interfacing to these inputs: 1. The input signal amplitude must be between 80mV and 1000mV. 2. The common mode voltage range must be as specified in the DC Characteristics Table (page 2). For 800mV input amplitude signals, this corresponds to a common mode voltage range between 2.8 and 4.6 volts. Figures 6 and 7 illustrate two methods of interfacing the GS9028 to the Gennum GS9024 (Cable Equalizer), GS9035 (Reclocker) or the GS9025 (Receiver). Figure 6 illustrates the simplest interface and is recommended when the trace lengths between the driver and the GS9028 are less than 0.5in. The pull up resistors should be placed near the GS9028 to serve as end terminations. VCC 10nF + _ VCC 100nF 10nF 75Ω 75Ω 75Ω 75Ω + _ GS9028 GS9028 GS9024 or GS9035 or GS9025 Fig. 7 The GS9028 can also be configured to accept ac coupled input signals. In this case, the inputs must be dc biased as illustrated in Figure 8. VCC 10nF R1 1µF R1 + _ 1µF R2 75Ω + _ GS9024 or GS9035 or GS9025 75Ω + _ GS9028 GS9028 R2 Fig. 8 The recommended values for R1 and R2 are: R1 = 1.35ZO Fig. 6 R2 = 3.85ZO When trace lengths become longer than 0.5in and data rates greater than 360Mb/s, electromagnetic reflections begin to affect signal integrity. To minimize reflections, controlled impedance traces and source and end terminations should be used as shown in Figure 7. Although terminations on both sides reduce the signal swing by a factor of two, the GS9028 is designed to meet this need with ultra low input amplitude requirements (as low as 80mV). This low input amplitude requirement also allows the use of 50Ω transmission lines (which are more robust and easier to control in multilayer boards) to interconnect the GS9024/25/35 and the GS9028. where ZO is the transmission line characteristic impedance. For 75Ω cable, R1 = 100Ω and R2 = 287Ω. OUTPUT INTERFACING Figure 9 illustrates the recommended interface for ac coupled outputs. VCC 10nF RT = R = ZO R RT + GS9028 RT L L R 1µF 1µF _ GS9028 Fig. 9 5 of 7 521 - 68 - 05 GS9028 The termination resistor (RT) value should be equal to the characteristic impedance of the cable. Controlled impedance traces should be used for the outputs and the termination resistors should be placed near the GS9028. The inductor (L) and resistor (R) are used to optimize the output return loss and are PCB dependent. Typically, R equals the transmission line characteristic impedance and L is approximately 8.2nH. OUTPUT AMPLITUDE ADJUSTMENT The GS9028 outputs are adjustable from as low as 50mV to as high as 1000mV. The output amplitude is set by the RSET resistor connected to pin 4. The relationship between the output amplitude (VOUT) and RSET is approximately given by the equation below: RSET = (1.3696 x ZO)/(2 x VOUT) - 5.5 where ZO is in ohms and VOUT is in volts. The minimum value of RSET is 46Ω. For 75Ω cable and 800mV output amplitudes, the value of RSET is 59Ω. Also, note that the above formula assumes that the transmission line is properly end terminated. TYPICAL APPLICATION CIRCUIT 5 6 7 8 VEE SDI GS9028 SDI VCC SDO 1 SDO 8.2nH 75 75 75 1µ 8.2nH 4 RSET 3 VEE 2 1µ 59 75 1µ 100n VCC 10n VCC All resistors in ohms, all capacitors in farads, unless otherwise shown. 6 of 7 521 - 68 - 05 PACKAGE DIMENSIONS 5.00 MAX. 0.49 MAX 1.91 MAX 1.27 MAX 8 5 4.0 MAX 6.20 MAX 0.25 MAX GS9028 1 4 0.25 MAX = = = 0.60 MAX 3.81 ±0.05 3 spaces @ 1.27 ±0.05 8 pin SOIC CAUTION ELECTROSTATIC SENSITIVE DEVICES DO NOT OPEN PACKAGES OR HANDLE EXCEPT AT A STATIC-FREE WORKSTATION DOCUMENT IDENTIFICATION DATA SHEET The product is in production. Gennum reserves the right to make changes at any time to improve reliability, function or design, in order to provide the best product possible. REVISION NOTES: Added lead-free and green information. GENNUM CORPORATION MAILING ADDRESS: P.O. Box 489, Stn. A, Burlington, Ontario, Canada L7R 3Y3 Tel. +1 (905) 632-2996 Fax. +1 (905) 632-5946 SHIPPING ADDRESS: 970 Fraser Drive, Burlington, Ontario, Canada L7L 5P5 GENNUM JAPAN CORPORATION Shinjuku Green Tower Building 27F 6-14-1, Nishi Shinjuku Shinjuku-ku, Tokyo 160-0023 Japan Tel: +81 (03) 3349-5501 Fax: +81 (03) 3349-5505 GENNUM UK LIMITED Centaur House, Ancells Bus. Park, Ancells Rd, Fleet, Hants, England GU13 8UJ Tel. +44 (0)1252 761 039 Fax +44 (0)1252 761 114 Gennum Corporation assumes no responsibility for the use of any circuits described herein and makes no representations that they are free from patent infringement. © Copyright April 1996 Gennum Corporation. All rights reserved. Printed in Canada. 7 of 7 521 - 68 - 05