Active RF Splitter ADA4302-4 FEATURES FUNCTIONAL BLOCK DIAGRAM Single 5 V supply 54 MHz to 865 MHz CATV operating range 4.6 dB of gain per output channel 4.4 dB noise figure 25 dB isolation between output channels −16 dB input return loss CSO of −73 dBc (135 channels, 15 dBmV per tone) CTB of −66 dBc (135 channels, 15 dBmV per tone) 1.3 GHz, −3 dB bandwidth VCC + GND VON4 VOP4 VCC VON3 VOP3 ILN VIP APPLICATIONS VIN J1 ILP VOP2 The ADA4302-4 is used as an active element in applications where a lossless signal split is required. Typical applications include multituner cable set-top boxes, cable splitter modules, multituner televisions, and home gateways where traditional solutions have consisted of discrete passive splitters followed by separate fixed gain amplifiers. The ADA4302-4 is a low cost alternative solution that simplifies designs and improves system performance by integrating a signal splitter element and gain element into a single IC solution. GND VON1 VOP1 05017-016 VCC GENERAL DESCRIPTION Figure 1. –55 –60 –65 CSO (dBc) The ADA4302-4 features four differential outputs. The differential architecture allows systems designed with the ADA4302-4 to maintain excellent linearity throughout the CATV band. The ADA4302-4 can also be configured for applications that require fewer than four outputs. Outputs can be configured independently from one another. VON2 TA = +85°C –70 TA = +25°C –75 TA = –40°C –80 –85 50 05017-008 Cable set-top boxes Home gateways CATV distribution systems Cable splitter modules SPLITTER GND 1000 100 FREQUENCY (MHz) Figure 2. Composite Second-Order (CSO) vs. Frequency Rev. B Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 © 2005 Analog Devices, Inc. All rights reserved. ADA4302-4 TABLE OF CONTENTS Features .............................................................................................. 1 Typical Performance Characteristics ..............................................6 Applications....................................................................................... 1 Applications........................................................................................8 General Description ......................................................................... 1 Circuit Description .......................................................................8 Functional Block Diagram .............................................................. 1 Evaluation Boards .........................................................................8 Revision History ............................................................................... 2 RF Layout Considerations............................................................8 Specifications..................................................................................... 3 Power Supply..................................................................................8 Absolute Maximum Ratings............................................................ 4 Outline Dimensions ....................................................................... 11 ESD Caution.................................................................................. 4 Ordering Guide .......................................................................... 11 Pin Configuration and Function Descriptions............................. 5 REVISION HISTORY 9/05—Rev. SpA to Rev. B Updated Format..................................................................Universal Changes to Circuit Description Section ........................................ 8 5/05—Rev. Sp0 to Rev. SpA Changes to Format .............................................................Universal Changes to Features.......................................................................... 1 Changes to Figure 1 and Figure 2................................................... 1 Changes to Table 1............................................................................ 3 Changes to Figure 4 and Figure 5................................................... 6 Changes to Applications Section .................................................... 8 10/04—Revision Sp0: Initial Version Rev. B | Page 2 of 12 ADA4302-4 SPECIFICATIONS VCC = 5 V, RIN = RL = 75 Ω, TA = 25°C, unless otherwise noted. The ADA4302-4 is characterized using a balun 1 at the input. Table 1. Parameter DYNAMIC PERFORMANCE Bandwidth (−3 dB) Specified Frequency Range Gain (S21) Gain Flatness NOISE/DISTORTION PERFORMANCE Composite Triple Beat (CTB) Composite Second-Order (CSO) Cross Modulation (CXM) Output IP3 Output IP2 Noise Figure INPUT CHARACTERISTICS Input Return Loss (S11) Output-to-Input Isolation (S12) OUTPUT CHARACTERISTICS Output Return Loss (S22) Output-to-Output Isolation 1 dB Compression POWER SUPPLY Nominal Supply Voltage Quiescent Supply Current 1 Conditions Min Typ Max Unit 865 5.7 MHz MHz dB dB −62 −67 −64 dBc dBc dBc 1300 54 3.5 f = 100 MHz f = 865 MHz 4.6 1 135 Channels, 15 dBmV/Channel, f = 103.25 MHz 135 Channels, 15 dBmV/Channel, f = 103.25 MHz 135 Channels, 15 dBmV/Channel, 100% modulation @ 15.75 kHz, f = 103.25 MHz f1 = 97.25 MHz, f2 = 103.25 MHz f1 = 97.25 MHz, f2 = 103.25 MHz @ 54 MHz @ 550 MHz @ 865 MHz −66 −73 −67 23 65 4.1 4.4 5.0 4.4 4.7 5.8 dBm dBm dB dB dB Referenced to 75 Ω @ 54 MHz @ 550 MHz @ 865 MHz Any output, 54 MHz to 865 MHz −16 −16 −18 −35 −14 −11 −11 −33 dB dB dB dB Referenced to 75 Ω @ 54 MHz @ 550 MHz @ 865 MHz Between any two outputs, 54 MHz to 865 MHz Output referred, f = 100 MHz −11 −12.5 −14 −25 8 −9 −10 −11.5 dB dB dB dB dBm 5 215 M/A-COM MABAES0029. Rev. B | Page 3 of 12 240 V mA ADA4302-4 ABSOLUTE MAXIMUM RATINGS Table 2. Parameter Supply Voltage Storage Temperature Range Operating Temperature Range Lead Temperature (Soldering 10 sec) Junction Temperature Rating 5.5 V −65°C to +125°C −40°C to +85°C 300°C 150°C Stresses above those listed under Absolute Maximum Rating may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ESD CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although this product features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality. Rev. B | Page 4 of 12 ADA4302-4 20 19 18 17 16 VON1 VOP1 GND VON2 VOP2 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS PIN 1 INDICATOR ADA4302-4 TOP VIEW (Not to Scale) 15 VON3 14 VOP3 13 VCC 12 VCC 11 ILP GND VIP GNDC VIN GND 05017-001 1 2 3 4 5 6 7 8 9 10 VOP4 VON4 VCC VCC ILN Figure 3. 20-Lead LFCSP_VQ Pin Configuration Table 3. Pin Function Descriptions Pin No. 1 2 3, 4, 12, 13 5 6, 10, 18 7 8 9 11 14 15 16 17 19 20 Mnemonic VOP4 VON4 VCC ILN GND VIP GNDC VIN ILP VOP3 VON3 VOP2 VON2 VOP1 VON1 Description Positive Output 4 Negative Output 4 Supply Pin Bias Pin Ground Positive Input Ground Negative Input Bias Pin Positive Output 3 Negative Output 3 Positive Output 2 Negative Output 2 Positive Output 1 Negative Output 1 Rev. B | Page 5 of 12 ADA4302-4 TYPICAL PERFORMANCE CHARACTERISTICS –55 7 –60 6 NOISE FIGURE (dB) TA = +85°C TA = +85°C –70 TA = +25°C –75 TA = –40°C 5 TA = +25°C 4 TA = –40°C 3 –85 50 05017-008 –80 2 50 1000 100 05017-006 CSO (dBc) –65 100 1000 FREQUENCY (MHz) FREQUENCY (MHz) Figure 7. Noise Figure vs. Frequency Figure 4. Composite Second-Order (CSO) vs. Frequency 90 –55 80 OUTPUT IP2 (dBm) CTB (dBc) –60 TA = +25°C –65 TA = –40°C 70 60 50 TA = +85°C –70 30 50 1000 100 05017-012 –75 50 05017-009 40 100 1000 FREQUENCY (MHz) FREQUENCY (MHz) Figure 8. Output IP2 vs. Frequency Figure 5. Composite Triple Beat (CTB) vs. Frequency 25 –55 20 OUTPUT IP3 (dBm) TA = –40°C –65 –70 TA = +85°C TA = +25°C 15 10 –75 50 100 0 50 1000 05017-013 5 05017-010 CXM (dBc) –60 100 1000 FREQUENCY (MHz) FREQUENCY (MHz) Figure 9. Output IP3 vs. Frequency Figure 6. Cross Modulation (CXM) vs. Frequency Rev. B | Page 6 of 12 ADA4302-4 10 0 TA = –40°C 5 –5 INPUT RETURN LOSS (dB) TA = +25°C TA = +85°C –5 –10 –10 –15 05017-003 –20 50 100 1000 FREQUENCY (MHz) –25 50 10000 –10 –5 OUTPUT RETURN LOSS (dB) ISOLATION (dB) 0 –20 –30 05017-005 –40 –10 –15 –20 –25 50 1000 100 FREQUENCY (MHz) 1000 FREQUENCY (MHz) Figure 11. Output-to-Input Isolation vs. Frequency (S12) Figure 14. Output Return Loss vs. Frequency (S22) 240 –5 –10 –15 –20 –25 –35 50 05017-007 –30 100 235 230 225 220 215 210 205 200 –60 1000 FREQUENCY (MHz) Figure 12. Output-to-Output Isolation vs. Frequency 05017-011 QUIESCENT SUPPLY CURRENT (mA) 0 ISOLATION (dB) 1000 Figure 13. Input Return Loss vs. Frequency (S11) 0 100 100 FREQUENCY (MHz) Figure 10. AC Response (S21) –50 50 05017-002 –20 –15 05017-004 GAIN (dB) 0 –40 –20 0 20 40 TEMPERATURE (°C) 60 80 Figure 15. Quiescent Supply Current vs. Temperature Rev. B | Page 7 of 12 100 ADA4302-4 APPLICATIONS The ADA4302-4 active splitter is primarily intended for use in the downstream path of television set-top boxes (STBs) that contain multiple tuners. It is located directly after the diplexer in a CATV customer premise unit. The ADA4302-4 provides a differential input and four differential outputs that allow the delivery of the RF signal to up to four different signal paths. These paths can include, but are not limited to, a main picture tuner, the picture-in-picture (PIP) tuner, a digital video recorder (DVR), and a cable modem (CM). The differential nature of the ADA4302-4 allows it to provide composite second-order (CSO) and composite triple beat (CTB) products that are −73 dBc and −66 dBc, respectively. The use of the SiGe process also allows the ADA4302-4 to achieve a noise figure (NF) that is less than 5 dB. CIRCUIT DESCRIPTION The ADA4302-4 has a low noise buffer amplifier that is followed by four parallel amplifiers. This arrangement provides 4.6 dB of gain relative to the RF signal present at the differential inputs of the active splitter. The input and each output must be properly matched to a differential 75 Ω environment in order for distortion and noise performance to match the data sheet specifications. If needed, baluns to convert to single-ended operation can be used. The M/A-COM MABAES0029 is recommended for the input balun and the Mini-Circuit® TC1-1-13M-2 is recommended for the output balun. AC coupling capacitors of 0.01 μF are recommended for all inputs and outputs. Two 1 μH RF chokes, L1 and L2 (Coilcraft chip inductor 0805LS-102X), are used to correctly bias internal nodes of the ADA4302-4 by connecting them between the 5 V supply and ILN and ILP, respectively. EVALUATION BOARDS There are two evaluation boards for the ADA4302-4, a singleended output board (ADA4302-4 EBSE) and a differential output board (ADA4302-4 EBDI). The single-ended output board has an input balun that converts a signal from a singleended source to a differential signal. The differential output board uses the same input balun and allows the output signals to run directly to the board connectors. This allows the differential signals at the ADA4302-4’s outputs to be applied directly to a tuner with differential inputs. The schematics for these evaluation boards can be seen in Figure 16 and Figure 17, respectively. Each board has place holders to properly terminate the unused outputs, if needed. On the single-ended output board, they are designated R15 through R18, and 75 Ω resistors should be used here (see Figure 16). On the differential output board, 37.5 Ω resistors should be used for R1, R2, and R4 through R9 when their respective outputs are not in use (see Figure 17). RF LAYOUT CONSIDERATIONS Appropriate impedance matching techniques are mandatory when designing a circuit board for the ADA4302-4. Improper characteristic impedances on traces can cause reflections that can lead to poor linearity. If the stage following the ADA4302-4 is a single-ended load with a 75 Ω impedance, then a balun should be used. The characteristic impedance of the signal trace from each output of a differential pair to the output balun should be 37.5 Ω. In the case of the differential output evaluation board, the output traces should also have a characteristic impedance of 37.5 Ω. POWER SUPPLY The 5 V supply should be applied to each of the VCC pins and RF chokes via a low impedance power bus. The power bus should be decoupled to ground using a 10 μF tantalum capacitor and a 0.01 μF ceramic chip capacitor located close to the ADA4302-4. In addition, the VCC pins should be decoupled to ground with a 0.01 μF ceramic chip capacitor located as close to each of the pins as possible. Pin 3 and Pin 4 can share one capacitor, and Pin 12 and Pin 13 can share one capacitor. Rev. B | Page 8 of 12 ADA4302-4 75Ω TRACE P4 G1 G2 G3 G4 37.5Ω TRACES VCC R15 DNI 3 T4 1 4 5 C3 0.01μF R2 DNI 75Ω TRACE AGND VCC + AGND C13 10μF C1 0.01μF C2 0.01μF C11 0.01μF AGND 75Ω TRACE AGND L2 1μH 5 VOP3 VON3 VOP4 VON4 4 75Ω TRACE AGND C4 0.01μF 14 15 16 17 75Ω TRACE VON2 75Ω TRACE 20 ILP 11 C19 0.01μF 1 R6 DNI DUT SPLITTER VOP2 AGND 37.5Ω TRACES 3 VIN 9 VON1 R3 DNI 4 VIP 7 1 GND 6 GND 10 GND 18 8 GNDC 19 VOP1 J1 75Ω TRACE T5 3 C5 0.01μF AGND 1 ILN 5 AGND 5 R16 DNI T3 2 L1 1μH C14 0.01μF 37.5Ω TRACES AGND 13 VCC 12 VCC VCC 4 3 VCC VCC P3 C10 0.01μF P2 37.5Ω TRACES R17 DNI VCC 3 T2 1 4 5 C9 0.01μF R8 DNI 75Ω TRACE AGND AGND C8 0.01μF AGND 75Ω TRACE P1 R18 DNI 3 1 4 5 C6 0.01μF R10 DNI 75Ω TRACE C7 0.01μF AGND AGND 05017-015 37.5Ω TRACES T1 Figure 16. Single-Ended Output Evaluation Board Table 4. ADA4302-4ACPZ-EBSE Bill of Materials (BOM) Quantity 2 4 1 13 1 1 5 9 Description Coilcraft 0805LS-102X Chip Inductor Mini-Circuit TC1-1-13M-2 Transformer M/A-COM MABAES0029 Transformer MLCC, 0.01 μF, C402 Tantalum, 10 μF, B Size ADA4302-4ACPZ SMA Connectors Impedance Matching Resistors, Insert as Needed Rev. B | Page 9 of 12 Reference L1, L2 T1 to T4 T5 C1 to C11, C14, C19 C13 DUT J1, P1 to P4 R2, R3, R6, R8, R10, R15 to R18 ADA4302-4 P4VDN R8 DNI C3 0.01μF G1 G2 G3 37.5Ω TRACES VCC G4 37.5Ω TRACES AGND VCC P4VDP C1 0.01μF AGND 75Ω TRACE L2 1μH VOP3 VON3 VOP4 P3VDP 14 1 15 16 17 VON2 ILP 11 C19 0.01μF AGND DUT SPLITTER VOP2 37.5Ω TRACES 3 VIN 9 20 4 VIP 7 1 VON1 75Ω TRACE T5 37.5Ω TRACES R2 DNI C4 0.01μF GND 6 GND 10 GND 18 8 GNDC 19 VOP1 J1 37.5Ω TRACES ILN 5 AGND 5 P3VDN R1 DNI C5 0.01μF AGND L1 1μH C14 0.01μF C2 0.01μF C10 0.01μF 13 VCC 12 VCC VCC 4 3 VCC VCC C11 0.01μF VON4 AGND C13 10μF 2 + R9 DNI P2VDN R4 DNI C9 0.01μF 37.5Ω TRACES 37.5Ω TRACES VCC AGND AGND R5 DNI P2VDP C8 0.01μF P1VDN R7 DNI C6 0.01μF 37.5Ω TRACES 37.5Ω TRACES P1VDP C7 0.01μF Figure 17. Differential Output Evaluation Board Table 5. ADA4302-4ACPZ-EBDI Bill of Materials (BOM) Quantity 2 1 13 1 1 9 8 Description Coilcraft 0805LS-102X Chip Inductor M/A-COM MABAES0029 Transformer MLCC, 0.01 μF, C402 Tantalum, 10 μF, B size ADA4302-4ACPZ SMA Connectors Impedance Matching Resistors, Insert as Needed Rev. B | Page 10 of 12 Reference L1, L2 T5 C1 to C11, C14, C19 C13 DUT J1, P1VDN to P4VDN, P1VDP to P4VDP R1, R2, R4 to R9 05017-014 AGND R6 DNI ADA4302-4 OUTLINE DIMENSIONS 0.60 MAX 4.00 BSC SQ 0.60 MAX PIN 1 INDICATOR TOP VIEW 20 1 16 15 2.25 2.10 SQ 1.95 3.75 BCS SQ 0.75 0.55 0.35 12° MAX 1.00 0.85 0.80 SEATING 0.50 PLANE BSC PIN 1 INDICATOR 11 10 0.80 MAX 0.65 TYP 5 0.25 MIN 0.30 0.23 0.18 0.05 MAX 0.02 NOM 0.20 REF 6 COPLANARITY 0.08 COMPLIANT TO JEDEC STANDARDS MO-220-VGGD-1 Figure 18. 20-Lead Lead Frame Chip Scale Package [LFCSP_VQ] 4 mm × 4 mm Body, Very Thin Quad (CP-20-1) Dimensions shown in millimeters ORDERING GUIDE Model ADA4302-4ACP-REEL ADA4302-4ACP-RL7 ADA4302-4ACPZ-RL 1 ADA4302-4ACPZ-RL71 ADA4302-4ACPZ-R21 ADA4302-4ACPZ-EBSE 2 ADA4302-4ACPZ-EBDI2 1 2 Ordering Quantity 5,000 1,500 5,000 1,500 250 1 1 Temperature Range −40°C to +85°C −40°C to +85°C −40°C to +85°C −40°C to +85°C −40°C to +85°C Z = Pb-free part. Evaluation board contains Pb-free part. Rev. B | Page 11 of 12 Package Description 20-Lead LFCSP_VQ 20-Lead LFCSP_VQ 20-Lead LFCSP_VQ 20-Lead LFCSP_VQ 20-Lead LFCSP_VQ Single-Ended Evaluation Board Differential Output Evaluation Board Package Option CP-20-1 CP-20-1 CP-20-1 CP-20-1 CP-20-1 ADA4302-4 NOTES © 2005 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05017–0–9/05(B) T T Rev. B | Page 12 of 12