Abstract: The RF input for a global positioning system (GPS) receiver is 1575MHz. Assuming an IF of 85MHz, and low-side LO injection (fLO = 1490MHz), the MAX2682 achieves +12.0dB of gain, has a noise figure of 9.2dB, an input third-order intercept point (IIP3) of +1.8dBm and draws 14.7mA of supply current from a +3.0V supply. Additional Information Wireless Product Line Page Quick View Data Sheet for the MAX2682/MAX2681/MAX2682 Downconverters Applications Technical Support The MAX2682 is one of a family of Silicon Germanium (SiGe) downconverters designed for low-voltage, low-current operation, and is ideal for portable communications equipment. The MAX2682 can be used with input radio frequencies (RFs) between 400MHz and 2500MHz, to downconvert to intermediate frequencies (IFs) between 10MHz to 500MHz. The RF input for a global positioning system (GPS) receiver is 1575MHz. Assuming an IF of 85MHz, and low-side LO injection (fLO = 1490MHz), the MAX2682 achieves +12.0dB of gain, has a noise figure of 9.2dB, an input third-order intercept point (IIP3) of +1.8dBm and draws 14.7mA of supply current from a +3.0V supply. See Figure 1 for component values and the schematic. For application of the MAX2682 at 900MHz, 1950MHz of 2450MHz, or for further device information, consult the MAX2680/MAX2681/MAX2682 Silicon Germanium (SiGe) Downconverters data sheet. Figure 1. MAX2682 Silicon Germanium (SiGe) downconverter mixer for GPS applications. Table 1. MAX2682 SiGe Downconverter GPS Performance VCC = +3.0V, fRF1 = 1575MHz, fRF2 = 1576MHz, fLO = 1490MHz, PLO = -5dBm, fIF = 85MHz Parameter Measured Performance Conversion Gain +12.0dB Noise Figure 9.2dB Input Third-Order Intercept Point +1.8dBm RF Input Return Loss -35dB IF Output Return Loss -23dB Supply Current 14.7mA We Want Your Feedback! Automatic Updates Would you like to be automatically notified when new application notes are published in your areas of interest? Sign up for EE-Mail™. More Information   APP 890: May 01, 2002 MAX2682 400MHz to 2.5GHz, Low-Noise, SiGe Downconverter Mixers Full Data Sheet (PDF, 200kB) Free Samples   Download, PDF Format (30kB)  AN890, AN 890, APP890, Appnote890, Appnote 890