ADRF6655

Data Sheet Broadband Up/Downconverting Mixer with Integrated Fractional-N PLL and VCO ADRF6655 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 Flexible IF output interface Input P1dB: 12 dBm Input IP3: 29 dBm Noise figure (SSB): 12 dB Voltage conversion gain: 6 dB Matched 200 Ω output impedance SPI serial interface for PLL programming 40-lead 6 mm × 6 mm LFCSP GENERAL DESCRIPTION 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. The programmable divider is controlled by an Σ-Δ modulator (SDM). The modulus of the SDM can be programmed between 1 and 2047. The broadband, active mixer employs a bias adjustment to allow for enhanced IP3 performance at the expense of increased supply current. The mixer provides an input IP3 exceeding 25 ...