Abstract: This application note presents the measured performance of the MAX3514/MAX3516 cable upstream amplifier. The measured data include 2nd Harmonics, 3rd Harmonics, output power vs. frequency, and ACPR. Tests are conducted using DOCSIS 2.0 as the standard, and the amplifiers are found to meet all requirements. Summary The upstream CATV amplifiers MAX3514/MAX3516 were tested for compliance to DOCSIS 2.0 PHY Requirements. The test results show that these ICs meet the DOCSIS 2.0 standards. DOCSIS 2.0 DOCSIS (Data-Over-Cable Service Interface Specification) are RF interface specifications for high-speed data-over-cable systems. DOCSIS 2.0 is the third generation of the DOCSIS specification. The terms DOCSIS 2.0, DOCSIS 1.1, and DOCSIS 1.0 refer to three different specifications. The DOCSIS 2.0 specification primarily aims at enhancing the limited upstream physical layer performance of a DOCSIS 1.0- or 1.1-based cable access system. Two new MAC (medium access controller) Management Message Types have been defined, and several new parameter encodings have been defined in the existing MAC messages. A DOCSIS 2.0 CMTS (cable modem termination system) is capable of supporting a higher upstream throughput for a given channel bandwidth as well as increased tolerance to noise experienced in the upstream. DOCSIS 2.0 CMTS is backward compatible with DOCSIS 1.0 and DOCSIS 1.1. The MAX3514/MAX3516 are a family of programmable-gain upstream amplifiers designed for use in CATV upstream applications. They operate over a frequency range of 5MHz to 65MHz and drives up to +64dBmV QPSK (MAX3516). Since both input and output ports are differential, an external balun at the output port is required. The variable gain feature provides greater than 56dB of dynamic range (MAX3514/MAX3516) and is controlled bya SPI 3-wire interface. Gain control is available in 0.5dB steps (MAX3514/MAX3516) or 1dB step (MAX3510). Measurements All tests at room temperature. VCC = 5.0V PIN = -13dBm (+34dBmV in 50Ω system, channel power) Input signal: QPSK modulation with 20b PRBS, root cosine filter, α= 0.25 16 QAM modulation with 20b PRBS, root cosine filter, α= 0.25 64 QAM modulation with 20b PRBS, root cosine filter, α= 0.25 High Power Mode Input ACPR -66dBc 160kHz measurement bandwidth (200kHz channel spacing) 320kHz measurement bandwidth (400kHz channel spacing) 640kHz measurement bandwidth (800kHz channel spacing) 1280kHz measurement bandwidth (1600kHz channel spacing) 2560kHz measurement bandwidth (3200kHz channel spacing) 5120kHz measurement bandwidth (6400kHz channel spacing) Corrections and Unit Conversion In 50Ω system, PIN/OUT (dBmV) = PIN/OUT (dBm) + 47dB In 75Ωsystem, PIN/OUT(dBmV) = PIN/OUT (dBm) + 49dB MAX3514/MAX3516EVKit boards have 7.5dB minimum loss pad at the output,so POUT (dBmV) = POUT (dBm) + 47dB + 7.5dB + cable loss Test Equipment List (See Figure 1 for typical test setup) Signal Generator capable of generating 64 QAM signals (RODHE & SCHWARZ SMIQ 06B) Spectrum Analyzer (RODHE & SCHWARZ FSEB) Power Meter (HP437B) Power Sensor (HP8482A) Power Supply (Agilent E3632A) DMM (HPE3631A) Figure 1. Test equipment set up. Results Test Signal: Modulation = 64 QAM Alpha = 0.25 Modulation Signal Center Frequency = 22MHz Symbol Rates: 160ksps, 320ksps, 640ksps, 1280ksps, 2560ksps, 5120ksps Table 1. The MAX3514 2nd and 3rd Harmonic vs. Output Power and Frequency : (+54dBmV to +58dBmV) 22MHz (160ksps) Input (dBm) GCW Output (dBm) Output (dBmv) 2nd Harm (dBc) 3rd Harm (dBc) -13 108 6.8 53.8 -61.7 -60.0 -13 110 7.8 54.8 -61.8 -60.0 -13 112 8.8 55.8 -61.9 -59.8 -13 114 9.8 56.8 -62.1 -59.4 -13 116 10.8 57.8 -62.3 -59.0 22MHz (320ksps) Input (dBm) GCW Output (dBm) Output (dBmv) 2nd Harm (dBc) 3rd Harm (dBc) -13 108 6.9 53.9 -61.0 -59.8 -13 110 7.9 54.9 -61.3 -59.7 -13 112 8.9 55.9 -61.4 -59.5 -13 114 9.9 56.9 -61.6 -59.2 -13 116 10.9 57.9 -61.7 -58.8 22MHz (640ksps) Input (dBm) GCW Output(dBm) Output (dBmv) 2nd Harm (dBc) 3rd Harm (dBc) -13 108 6.8 53.8 -59.8 -58.6 -13 110 7.8 54.8 -60.0 -58.6 -13 112 8.8 55.8 -60.2 -58.7 -13 114 9.8 56.8 -60.4 -58.6 -13 116 10.8 57.8 -60.6 -58.8 22MHz (1280ksps) Input (dBm) GCW Output (dBm) Output (dBmv) 2nd Harm (dBc) 3rd Harm (dBc) -13 109 7.1 54.1 -58.4 -58.0 -13 111 8.1 55.1 -58.8 -58.1 -13 113 9.1 56.1 -59.1 -58.1 -13 115 10.1 57.1 -59.2 -57.7 -13 117 11.0 58.0 -59.4 -57.4 22MHz (2560ksps) Input (dBm) GCW Output (dBm) Output (dBmv) 2nd Harm (dBc) 3rd Harm (dBc) -13 109 7.0 54.0 -56.1 -56.5 -13 111 8.0 55.0 -56.3 -56.9 -13 113 9.0 56.0 -56.6 -57.2 -13 115 10.0 57.0 -57.0 -57.3 -13 117 11.0 58.0 -57.2 -56.7 22MHz (5120ksps) Input (dBm) GCW Output (dBm) Output (dBmv) 2nd Harm (dBc) 3rd Harm (dBc) -13 109 7.1 54.1 -53.5 -54.6 -13 111 8.1 55.1 -54.1 -55.0 -13 113 9.1 56.1 -54.6 -55.1 -13 115 10.1 57.1 -54.9 -55.1 -13 117 11.1 58.1 -55.4 -55.3 Table 2. DOCSIS 2.0 Specifications on 2nd and 3rd Order Harmonics (57dBmV output) Modulation Rate (ksps) 160 320 640 1280 2560 5120 2nd order harmonics DOCSIS 2.0 Spec. (dBc) -47 -50 -50 -50 -50 -50 3rd order harmonics DOCSIS 2.0 Spec. (dBc) -47 -50 -50 -50 -50 -50 Figure 2. Figure 3. Table 3. The MAX3516 2nd Harmonic vs. Output Power and Frequency (+57dBmV to +61dBmV) 22MHz (160ksps) Input (dBm) GCW Output (dBm) Output (dBmv) 2nd Harm (dBc) 3rd Harm (dBc) -13 108 10.0 57.0 -66.0 -60.7 -13 110 11.0 58.8 -66.5 -60.7 -13 112 12.0 59.0 -67.0 -59.7 -13 114 13.0 60.0 -67.7 -58.4 -13 116 14.0 61.0 -68.5 -56.5 22MHz (320ksps) Input (dBm) GCW Output (dBm) Output (dBmv) 2nd Harm (dBc) 3rd Harm (dBc) -13 108 10.0 57.0 -64.8 -60.3 -13 110 11.0 58.0 -65.1 -60.0 -13 112 12.0 59.0 -65.6 -59.1 -13 114 13.0 60.0 -66.3 -58.0 -13 116 14.0 61.0 -67.0 -56.4 22MHz (640ksps) Input (dBm) GCW Output (dBm) Output (dBmv) 2nd Harm (dBc) 3rd Harm (dBc) -13 108 10.0 57.0 -63.1 -59.8 -13 108 11.0 58.0 -63.4 -59.8 -13 110 12.0 59.0 -63.7 -59.1 -13 112 13.0 60.0 -64.4 -58.4 -13 114 14.0 61.0 -65.0 -56.6 22MHz (1280ksps) Input (dBm) GCW Output (dBm) Output (dBmv) 2nd Harm (dBc) 3rd Harm (dBc) -13 108 10.0 57.0 -61.2 -59.1 -13 110 11.0 58.0 -61.3 -59.0 -13 112 12.0 59.0 -61.8 -58.5 -13 114 13.0 60.0 -62.2 -57.5 -13 116 14.0 61.0 -62.7 -56.0 22MHz (2560ksps) Input (dBm) GCW Output (dBm) Output (dBmv) 2nd Harm (dBc) 3rd Harm (dBc) -13 108 9.8 56.8 -58.0 -57.7 -13 110 10.8 57.8 -58.5 -57.7 -13 112 11.8 58.8 -59.0 -57.4 -13 114 12.8 59.8 -59.5 -56.7 -13 116 13.8 60.8 -59.8 -55.6 22MHz (5120ksps) Input (dBm) GCW Output (dBm) Output (dBmv) 2nd Harm (dBc) 3rd Harm (dBc) -13 108 9.8 56.8 -55.3 -55.7 -13 110 10.8 57.8 -55.7 -55.8 -13 112 11.8 58.8 -56.0 -55.8 -13 114 12.8 59.8 -56.3 -55.4 -13 116 13.8 60.8 -56.7 -54.6 Table 4. DOCSIS 2.0 Specifications on 2nd and 3rd Order Harmonics (60dBmV output) Modulation Rate (ksps) 160 320 640 1280 2560 5120 2nd order harmonics DOCSIS 2.0 Spec. (dBc) -47 -50 -50 -50 -50 -50 3rd order harmonics DOCSIS 2.0 Spec. (dBc) -47 -50 -50 -50 -50 -50 Figure 4. Figure 5. Table 5. The MAX3514 ACPR vs. Output Power and Frequency 39MHz (160ksps) Input (dBm) GCW Output (dBm) Output (dBmv) ACPR (dBc) -13 109 7.0 54.0 -55.5 -13 111 8.0 55.0 -54.4 -13 113 9.0 56.0 -53.2 -13 115 10.0 57.0 -52.0 -13 117 11.0 58.0 -50.9 39MHz (320ksps) Input (dBm) GCW Output (dBm) Output (dBmv) ACPR (dBc) -13 109 7.0 54.0 -54.8 -13 111 8.0 55.0 -54.2 -13 113 9.0 56.0 -53.3 -13 115 10.0 57.0 -52.2 -13 117 11.0 58.0 -51.0 39MHz (640ksps) Input (dBm) GCW Output (dBm) Output (dBmv) ACPR (dBc) -13 109 7.0 54.0 -53.9 -13 111 8.0 55.0 -53.3 -13 113 9.0 56.0 -52.1 -13 115 10.0 57.0 -51.4 -13 117 11.0 58.0 -50.2 39MHz (1280ksps) Input (dBm) GCW Output (dBm) Output (dBmv) ACPR (dBc) -13 109 6.8 53.8 -52.2 -13 111 7.8 54.8 -51.6 -13 113 8.8 55.8 -50.8 -13 115 9.8 56.8 -50.0 -13 117 10.8 57.8 -48.6 39MHz (2560ksps) Input (dBm) GCW Output (dBm) Output (dBmv) ACPR (dBc) -13 109 7.0 54.0 -49.3 -13 111 8.0 55.0 -48.4 -13 113 9.0 56.0 -48.0 -13 115 10.0 57.0 -47.1 -13 117 11.0 58.0 -46.3 39MHz (5120ksps) Input (dBm) GCW Output (dBm) Output (dBmv) ACPR (dBc) -13 109 6.8 53.8 -46.2 -13 111 7.8 54.8 -45.6 -13 113 8.8 55.8 -45.1 -13 115 9.8 56.8 -44.3 -13 117 10.8 57.8 -43.5 Table 6. Adjacent Channel Power Ratio DOCSIS 2.0 Specifications Modulation Rate (ksps) 160 320 640 1280 2560 5120 ACPR DOCSIS 2.0 SPec. (dBc) -47 -47 -46 -45 -44 -42 Table 7. The MAX3516 ACPR vs. Output Power and Frequency 39MHz (160ksps) Input (dBm) GCW Output (dBm) Output (dBmv) ACPR (dBc) -13 109 10.2 57.2 -52.0 -13 111 11.2 58.2 -50.9 -13 113 12.2 59.2 -49.4 -13 115 13.2 60.2 -47.8 -13 117 14.2 61.2 -46.0 39MHz (320ksps) Input (dBm) GCW Output (dBm) Output (dBmv) ACPR (dBc) -13 108 9.9 56.9 -52.2 -13 110 10.8 57.8 -50.9 -13 112 11.8 58.8 -49.8 -13 114 12.8 59.8 -48.4 -13 116 13.8 60.8 -46.9 39MHz (640ksps) Input (dBm) GCW Output (dBm) Output (dBmv) ACPR (dBc) -13 109 10.3 57.3 -50.7 -13 111 11.2 58.2 -49.8 -13 113 12.2 59.2 -48.7 -13 115 13.2 60.2 -47.3 -13 117 14.2 61.2 -45.7 39MHz (1280ksps) Input (dBm) GCW Output (dBm) Output (dBmv) ACPR (dBc) -13 109 10.1 57.1 -49.6 -13 111 11.0 58.0 -48.7 -13 113 12.1 59.1 -47.6 -13 115 13.0 60.0 -46.5 -13 117 14.0 61.0 -44.9 39MHz (2560ksps) Input (dBm) GCW Output (dBm) Output (dBmv) ACPR (dBc) -13 109 10.2 57.2 -46.7 -13 111 11.1 58.1 -46.0 -13 113 12.1 59.1 -45.0 -13 115 13.1 60.1 -43.8 -13 117 14.1 61.1 -42.6 39MHz (5120ksps) Input (dBm) GCW Output (dBm) Output (dBmv) ACPR (dBc) -13 109 10.2 57.2 -43.8 -13 111 11.2 58.2 -43.1 -13 113 12.2 59.2 -42.2 -13 115 13.2 60.2 -41.4 -13 117 14.2 61.2 -40.3 Table 8. Adjacent Channel Power Ratio DOCSIS 2.0 Specifications Modulation Rate (ksps) 160 320 640 1280 2560 5120 ACPR DOCSIS 2.0 SPec. (dBc) -47 -47 -46 -45 -44 -42 Figure 6. Figure 7. Conclusion The test results in Table 1, 3, 5, 7 show that MAX3514/MAX3516 meet the DOCSIS 2.0 standards. 관련 부품   APP 1945: Mar 25, 2003 MAX3510 업스트림 CATV 앰프 전체 데이터 시트 (PDF, 156kB) MAX3514 업스트림 CATV 앰프 전체 데이터 시트 (PDF, 532kB) 무료 샘플 MAX3516 업스트림 CATV 앰프 전체 데이터 시트 (PDF, 532kB) 무료 샘플 자동 업데이트 관심 분야의 애플리케이션 노트가 나올 때 자동으로 업데이트를 원하십니까? 그렇다면 EE-Mail™을 신청하십시오. We Want Your Feedback! 의견을 보내주세요! 위 내용이 도움이 되셨나요? 여러분의 의견을 기다립니다 — Maxim은 보내주신 정정이나 제안사항을 반영하고 있습니다. 이 페이지를 평가하고 의견을 보내주십시오.   다운로드, PDF 형식 (103kB)  AN1945, AN 1945, APP1945, Appnote1945, Appnote 1945