7.1 Overview

The LMX8410L is a high-performance I/Q demodulator with an RF input range of 4 to 10 GHz and an IF output range of DC to 1350 MHz. This device integrates many components to allow high system performance as well as simplified design. There is an integrated synthesizer that generates wide-band frequencies at very low phase noise, with signal carefully conditioned for driving the mixer LO port. The RF input is single ended, enabled by an integrated wide-band RF balun at the front end. The two mixers on each I/Q channel are highly linear with optimized filtering and interfacing with components on each port. The IF amplifier is a high gain and high linearity component, saving users from matching discrete amplifiers and being restricted by common mode voltages typically encountered when interfacing mixers and ADC’s. In addition to high linearity and low noise performance, the LMX8410L comes equipped with many features to further optimize certain parameters. The automatic DC offset calibration is run by an internal automatic algorithm which will sense and tune the DC offset between the N and P sides of the differential signal of each IF amplifier, thus ensuring optimal performance when directly DC coupled to the ADC. The I/Q calibration knob allows tuning blocks within the mixer and IF amplifier to balance both the gain and the phase of the I/Q output signals, thus giving the user capability to adjust and achieve high image rejection. The internal synthesizer also has a feature of synchronization, which allows multiple LMX8410L designed in parallel to have synchronized LO signal phase.