The MAX2117 zero-IF (ZIF) tuner for UHF-band MMDS applications receives QPSK signals in the 470 to 1000MHz range, and downconverts them to baseband for demodulation. Specifically designed for China's UHF-band MMDS systems, the MAX2117, developed by Maxim Integrated Products, is compatible with most DVB-S demodulators. A low 8dB (typ.) noise figure, combined with a better than 25dB (typ.) adjacent-channel protection ratio (ACPR), makes this device ideal for MMDS applications. It operates from a single, 3.3V ±5% supply and consumes only 330mW. Though it has been designed to operate with a low-cost 4MHz crystal, an internal reference divider allows the user to select any crystal in the 4MHz to 8MHz range.
