Linear Technology announces the LTC5548, a double balanced mixer that operates either as an up- or downconverter with an exceptionally wide frequency range from 2GHz to 14GHz. The LTC5548 features integrated balun transformers at the RF and LO ports, providing 50Ω match from 2GHz to 13.6GHz and from 1GHz to 12GHz at each port, respectively, while enabling single-ended operation. Additionally, the IF port is capable of DC to 6GHz, supporting wideband transmitters and receivers at the baseband. The LTC5548 has high linearity of 24.4dBm IIP3 at 5.8GHz, and 21.4dBm at 9GHz.
The LTC5548 simplifies microwave transmitter and receiver designs with its integrated LO buffer, requiring only a 0dBm drive, effectively eliminating an external high power LO amplifier circuit. Moreover, the LTC5548 has a selectable on-chip LO frequency doubler, enabling the device to use lower cost, commonly available low frequency synthesizers. The LTC5548 mixer features exceptional port-to-port isolation, minimizing undesirable LO leakage, easing external filtering requirements.
The LTC5548’s performance is ideal for a wide range of microwave applications, including broadband microwave backhaul, the emerging 5.8GHz unlicensed band and 14GHz LTE-Advanced broadband wireless services, satellite broadband transceivers, radar systems, X-band and Ku band transceivers, spectrum analyzers, RF test equipment and satellite modems.
The LTC5548 has exceptionally robust ESD handling capability of 2,000V ESD human body model (HBM) rating on all pins. The device comes in a tiny 12-lead 3mm x 2mm plastic QFN package, providing a compact solution footprint, requiring minimal external components. The device is rated for operation from -40°C to 105°C case temperature. The mixer is powered from a single 3.3V supply, drawing a nominal supply current of 120mA. Additionally, the LTC5548 has an enable pin to shut down the IC. When deactivated, the device draws only 100µA maximum standby current. The enable pin can be driven directly to turn the device on and off rapidly in less than 0.2µs, supporting time-division duplex (TDD) or burst mode type radios.