GS2978CNE3

GS2978 HD-LINX® III Multi-Rate Dual Slew-Rate Cable Driver GS2978 Data Sheet Features Description • SMPTE 424M, SMPTE 292M, SMPTE 344M and SMPTE 259M compliant The GS2978 is a high-speed BiCMOS integrated circuit designed to drive one or two 75Ω co-axial cables. • Dual coaxial cable driving outputs with selectable slew rate • 50Ω differential PECL input • Pb-free and RoHS compliant The GS2978 may drive data rates up to 2.97Gb/s and provides two selectable slew rates in order to achieve compliance to SMPTE 424M, SMPTE 259M, SMPTE 344M and SMPTE 292M. • Seamless interface to other HD-LINX® III family products • Single 3.3V power supply operation • Operating temperature range: 0°C to 70°C Applications • SMPTE 424M, SMPTE 292M, SMPTE 344M and SMPTE 259M Coaxial Cable Serial Digital Interfaces. The GS2978 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 GS2978 is Pb-free, and the encapsulation compound does not contain halogenated flame retardant. This component and all homogeneous subcomponents are RoHS compliant. BANDGAP REFERENCE AND BIASING CIRCUIT DDI INPUT DIFFERENTIAL PAIR RSET SDO OUTPUT STAGE & CONTROL DDI SDO SD/HD DISABLE Functional Block Diagram 37186 - 5 October 2007 1 of 14 www.gennum.com GS2978 Data Sheet Contents Features ........................................................................................................................1 Applications...................................................................................................................1 Description ....................................................................................................................1 1. Pin Out ......................................................................................................................3 1.1 Pin Assignment ...............................................................................................3 1.2 Pin Descriptions ..............................................................................................3 2. Electrical Characteristics ...........................................................................................4 2.1 Absolute Maximum Ratings ............................................................................4 2.2 DC Electrical Characteristics ..........................................................................4 2.3 AC Electrical Characteristics ...........................................................................5 2.4 Solder Reflow Profiles .....................................................................................6 3. Input / Output Circuits ...............................................................................................7 4. Detailed Description ..................................................................................................8 4.1 Input Interfacing ..............................................................................................8 4.2 Output Interfacing ...........................................................................................8 4.2.1 Output Amplitude (RSET) ......................................................................9 4.2.2 Output Disable .......................................................................................9 4.3 Output Return Loss Measurement ..................................................................9 5. Application Information............................................................................................10 5.1 PCB Layout ...................................................................................................10 5.2 Typical Application Circuit .............................................................................10 6. Package & Ordering Information .............................................................................11 6.1 Package Dimensions ....................................................................................11 6.2 Recommended PCB Footprint ......................................................................12 6.3 Packaging Data .............................................................................................12 6.4 Marking Diagram ...........................................................................................13 6.5 Ordering Information .....................................................................................13 7. Revision History ......................................................................................................14 37186 - 5 October 2007 2 of 14 GS2978 Data Sheet 1. Pin Out DDI 1 DDI 2 NC NC NC NC 1.1 Pin Assignment 16 15 14 13 12 SDO 11 SDO GS2978 (top view) VEE 3 10 SD / HD RSET 4 9 VCC 8 NC DISABLE NC 7 RSVD 6 5 Center Pad (bottom of package) Figure 1-1: 16-Pin QFN 1.2 Pin Descriptions Table 1-1: Pin Descriptions Pin Number Name Timing Type Description DDI, DDI Analog Input Serial digital differential input. 3 VEE – Power Most negative power supply connection. Connect to GND. 4 RSET Analog Input External output amplitude control resistor. NC – – No Connect. Not bonded internally. 7 RSVD – Reserved Do not connect. 6 DISABLE Non Synchronous Input Serial output disable. When asserted LOW, the SDO/SDO output driver is powered off. SDO/SDO will float to VCC through the pull-up resistor. 9 VCC – 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 SMPTE424M and 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 12. 1,2 5,8,13,14, 15,16 37186 - 5 October 2007 3 of 14 GS2978 Data Sheet 2. Electrical Characteristics 2.1 Absolute Maximum Ratings Parameter Value Supply Voltage -0.5V to 3.6 VDC Input ESD Voltage 4kV 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 NOTE: Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions or at any other condition beyond those indicated in the AC/DC Electrical Characteristic sections is not implied. 2.2 DC Electrical Characteristics Table 2-1: DC Electrical Characteristics VCC = 3.3V ±5%; TA = 0°C to 70°C, unless otherwise shown Parameter Symbol Conditions Min Typ Max Units Supply Voltage VCC – 3.135 3.3 3.465 V Power Consumption PD TA = 25°C, SDO/SDO enabled – 168 – mW TA = 25°C, SDO/SDO disabled – 96 – mW TA = 25°C, SDO/SDO enabled – 51 – mA TA = 25°C, SDO/SDO disabled – 29 – mA Supply Current Is Output Voltage VCMOUT Common mode – VCC - VOUT – V Input Voltage VCMIN Common mode 1.4 + ΔVDDI/2 – VCC - ΔVDDI/2 V SD/HD, DISABLE Input VIH IIH