更多信息 - 无线主页 - 应用笔记和技术讲座 - 评估板软件 - 技术支持   Abstract: The MAX3540 integrated, single-conversion terrestrial tuner IC for ATSC and NTSC is A/74 compliant. The MAX3540 converts a RF input signal in the 54MHz to 860MHz band to a 44MHz balanced-IF output. Figure 1. The evaluation board for the MAX3540 single-conversion terrestrial tuner for ATSC/NTSC. Figure 2. Tuner system block diagram. Lab Measurements The ATSC system performance of the MAX3540 with an ATSC demodulator is shown below. Figure 3. Desired-to-undesired ratio (D/U) measurements meet the A/74 specification with at least 2dB of margin. These measurements are for a weak desired signal at -68dBm with an ATSC undesired signal. Parameter Measured A/74 Specification Unit Sensitivity -85 typical -83 dBm Maximum Signal -2 typical -8 dBm Table 1. The margin to A/74 is typically 2dB for sensitivity and 6dB for maximum signal. Figure 4. The ATSC/NTSC RF signal is broadcast in the VHF Low, VHF High, and UHF bands, as shown above. The channel spacing is 6MHz. Detailed Description The MAX3540 is a complete single-conversion television tuner designed for use in analog/digital terrestrial applications and digital set-top boxes. This television tuner draws only 760mW of power from a +3.3V supply voltage. The MAX3540 is designed to convert NTSC or ATSC signals in the 54MHz to 860MHz band to a 44MHz intermediate frequency (IF). The MAX3540 includes a variable-gain low-noise amplifier, multiband tracking filters, a harmonic-rejection mixer, a low-noise IF amplifier, an IF power detector, and a variable-gain IF amplifier. The MAX3540 also includes fully-monolithic VCOs and tank circuits, as well as, a complete frequency synthesizer. This highly integrated design allows for low-power tuner-on-board applications without the cost and power-dissipation issues of dual-conversion tuner solutions. The MAX3540 is specified for operation in the 0°C to +85°C temperature range, and is available in a leadless 48-pin flip-chip (fcLGA) package. 我们期待您的反馈！ 喜欢？不喜欢？有待改善？或为我们提供建议？请与我们联系 — 我们将根据您的意见或建议改善我们的工作。 网页评价或提供建议 自动更新 需要自动接收最新发布的应用笔记吗？请订阅EE-Mail™ (English only)。 更多信息   APP 4176: Jun 13, 2008 MAX3540 完备的一次变频电视调谐器 完整的数据资料 (PDF, 276kB)   下载，PDF格式 (97kB)  AN4176, AN 4176, APP4176, Appnote4176, Appnote 4176