Modern digital transmitters take advantage of using high-order modulation to maximize data throughput rate while minimizing spectral bandwidth, thus allowing more efficient use of the frequency spectrum. I/Q modulators allow baseband signals to directly modulate onto the RF carrier. Such modulators typically suffer from excessive sideband and carrier leakage which, if not minimized, distort the transmitted signals. The LTC5599 is a very low power modulator with excellent sideband rejection and carrier leakage suppression, and with on-chip facilities to adjust these performance metrics to unprecedented levels. The device also has an exceptionally low output noise floor and high linearity, producing superior dynamic range performance for mission-critical transmitters.