Tuner Circuit Reduces Noise and Distortion
Reducing noise and distortion in CATV set-top boxes, DVRs, PC TV tuner cards and other tuner-on-board applications, the AIT1032 from Anadigics, is a 1 GHz tuner that incorporates an upconverter, downconverter, VCO, synthesizer, RF and IF amplifier, and RF and IF gain control functions. The tuner also provides two 45 MHz IF outputs, one for analog signals and one for digital signals. The digital output offers 78dB (typ) conversion gain, with an adjustable IF amplifier stage having 45dB of gain control range. The analog output provides 65dB conversion gain via a fixed IF output amplifier. The single RF input to the device contains a low noise amplifier with 35dB of gain control range. The tuner operates from a single +5V supply and includes on-chip oscillator tank circuits. It is offered in a 7 mm x 7 mm x 1 mm 48-pin surface mount package and is available with a full reference design.