Linear Technology has introduced the LTC5548, a double-balanced mixer that operates either as an up- or down-converter with a wide frequency range from 2 GHz to 14 GHz. The LTC5548 features integrated balun transformers at the RF and LO ports, providing 50 Ω match from 2 GHz to 13.6 GHz and from 1 GHz to 12 GHz at each port, respectively, while enabling single-ended operation. Additionally, the IF port is capable of DC to 6 GHz, supporting wideband transmitters and receivers at the baseband. The LTC5548 has high linearity of 24.4 dBm IIP3 at 5.8 GHz, and 21.4 dBm at 9 GHz.
Linear Technology’s LTC5548 mixer (Image courtesy of Linear Technology).The LTC5548 simplifies microwave transmitter and receiver designs with its integrated LO buffer, requiring only a 0 dBm 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 also provides good port-to-port isolation, minimizing undesirable LO leakage and easing external filtering requirements.
The LTC5548 handles ESD voltages up to 2,000 V on all pins. The device is rated for operation from -40 °C to 105 °C. The mixer is powered from a single 3.3 V supply and draws a nominal supply current of 120 mA.
Additionally, the mixer has an enable pin to shut down the IC. When deactivated, the device draws only 100 µA maximum standby current. The enable pin can be driven directly to turn the device on and off rapidly in less than 0.2 µs, supporting time-division duplex (TDD) or burst mode-type radios.
The LTC5548’s performance is suited for various microwave applications, including broadband microwave backhaul, the emerging 5.8 GHz unlicensed band and 14 GHz 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 comes in a 12-lead 3 mm x 2 mm plastic QFN package. List price starts at $9.50 each in 1,000-piece quantities. Samples and production quantities are available immediately.
