The ADRF6655 is a high dynamic range active mixer with integrated PLL and VCO. The synthesizer uses a programmable integer-N/fractional-N PLL to generate a local oscillator input to the mixer. The PLL reference input is nominally 20 MHz. The reference input can be divided by or multiplied by and then applied to the PLL phase detector. The PLL can support input reference frequencies from 10 MHz to 160 MHz. The phase
detector output controls a charge pump whose output is integrated in an off-chip loop filter. The loop filter output is then applied to an integrated VCO. The VCO output at 2 × fLO is then applied to a local oscillator (LO) divider as well as to a programmable PLL divider.
**FEATURES**
**Broadband active mixer with integrated fractional-N PLL**
**RF input frequency range: 100 MHz to 2500 MHz**
**Internal LO frequency range: 1050 MHz to 2300 MHz**