LMX2594 Wideband Synthesizer

Texas Instruments' LMX2594 is a high-performance, wideband synthesizer that can generate any frequency from 10 MHz to 15 GHz without using an internal doubler, thus eliminating the need for sub-harmonic filters. The high performance PLL with figure of merit of -236 dBc/Hz and high-phase detector frequency can attain very low in-band noise and integrated jitter. The high-speed N-divider has no pre-divider, thus significantly reducing the amplitude and number of spurs. There is also a programmable input multiplier to mitigate integer boundary spurs.

The LMX2594 allows users to synchronize the output of multiple devices and also enables applications that need deterministic delay between input and output. A frequency ramp generator can synthesize up to twosegments of ramp in an automatic ramp generation option or a manual option for maximum flexibility. The fast calibration algorithm allows changing frequencies faster than 20 µs. The LMX2594 adds support for generating or repeating SYSREF (compliant to JESD204B standard) making it an ideal low-noise clock source for high-speed data converters. Fine delay adjustment (9 ps resolution) is provided in this configuration to account for delay differences of board traces.

The output drivers within LMX2594 deliver output power as high as 7 dBm at 15 GHz carrier frequency. The device runs from a single 3.3 V supply and has integrated LDOs that eliminate the need for on-board low noise LDOs.