资 源 简 介
The STV6110A satellite tuner is a directconversion(zero IF) receiver dedicated to digitalTV broadcasTIng.On the RF input is a low noise amplifier (LNA),with buffer to supply the RF output forloop-through, and a conTInuously variable gainLNA to ensure an opTImal signal level for the twomixers. Each mixer, which down-converts thesignal to baseband, is followed by a low-pass filterand amplifier. The baseband gain can be variedby programming a register via the I2C bus.The LO signals are provided by an integrated PLLwhich contains an on-chip voltage controlledoscillator (VCO) meeTIng stringent phase noiserequirements. The PLL loop filter is integrated.The LO frequencies are programmable.The comparison frequency for the phasefrequencydetector (PFD) is generated by dividingthe crystal oscillator reference frequency. Thecrystal frequency can be from 16 MHz to 32 MHzdepending on application.
