ADMV4540 Datasheet | Analog Devices

FEATURES - Fractional-N synthesizer with low phase noise VCO - K band quadrature demodulator - Programmable via 4-wire SPI - RF operating frequency range: 17 GHz to 22 GHz - LO internal frequency range: 17 GHz to 21.5 GHz - Double sideband noise figure: 5 d B at maximum conversion gain - Output integrated phase noise, 1 k Hz to 10 MHz: <1° - Maximum conversion gain of >50 d B - Conversion gain control range of >50 d B - IM3 of - 54 d Bc at - 30 d Bm posite input level, Δf RF = 1 MHz - 3 baseband, SPI-selectable LPFs with corner frequencies of: 125 MHz, 250 MHz, and 500 MHz on each baseband path APPLICATIONS - Satellite munications GENERAL DESCRIPTION The ADMV4540 is a highly integrated quadrature demodulator with integrated synthesizer ideally suited for next generation K band satellite munication. The RF front end of the ADMV4540 consists of two low noise amplifier (LNA) paths, each with an optimal cascaded, 5 d B, double sideband noise figure at maximum gain, while minimizing external ponents. The dual paths allow support for antenna polarization. Selection of the LNA path can be done through the SPI. The LNA output is then downconverted to baseband using an inphase and quadrature (I/Q) mixer. The I/Q mixer output is then fed into fully differential low noise and low distortion programmable filters and variable gain amplifiers (VGAs). Each channel is capable of rejecting large, out of band interferers while reliably boosting the wanted signal, thus reducing the bandwidth and resolution requirements on the analog-to-digital converters (ADCs) of the system. The excellent matching between channels and their high spurious-free dynamic range (SFDR) over all gain and bandwidth settings make the ADMV4540 ideal for satellite munication systems with dense constellations, multiple carriers, and nearby interferers. The three filter corners of 125 MHz, 250 MHz, and 500 MHz are all programmable via a serial peripheral interface (SPI). The filters provide a sixth-order Butterworth...