Linear Technology Corporation introduces double balanced mixers

     Linear Technology Corporation introduces a double-balanced mixer, the LTC5549, that operates as both an up-converter and a down-converter with a very wide RF frequency range of 2GHz to 14GHz. The LTC5549 delivers excellent 24.4dBm IIP3 high linearity at 9GHz. The device incorporates an LO buffer that requires only a 0dBm drive level and can be used to enable high-efficiency microwave transmitter and receiver designs, effectively eliminating external high-power LO amplifier circuits.

     In addition, the LTC5549 features an integrated on-chip, switchable frequency multiplier for the LO signal, providing an option to use a lower cost and commonly used low frequency synthesizer. The LTC5549 utilizes a wideband integrated balanced-unbalanced transformer optimized for extending the RF frequency bandwidth from 2GHz to 14GHz, while enabling single-ended operation. Its IF port also offers broadband bandwidth up to 6GHz. All three ports are 50 Ohm matched. The mixer provides high port-to-port isolation, which minimizes unwanted LO leaks and reduces external filtering requirements.

     The LTC5549's superior performance improves a wide range of microwave applications, including microwave backhaul, open-band high-bandwidth LTE-Advanced base stations, satellite broadband radios, radar systems, X-band and Ku-band transceivers, test equipment, and satellite modems.

     The LTC5549 offers improved ESD protection with 2,000V ESD Mannequin (HBM) ratings on all pins. The device comes in a slim 12-pin, 3mm x 2mm plastic QFN package. With its design with few external components, the LTC5549 enables a compact solution to the board area. The device specifications operate in the case temperature range of -40 °C to 105°C to support extended ambient operating temperatures.

     The device is optimized for use with a single 3.3V operating supply and absorbs a nominal supply current of 115mA. In addition, the LTC5549 has an enable pin for deactivating the IC. When deactivated, the device only absorbs a maximum standby current of 100μA. Enable pins can be directly driven to quickly switch devices on and off in less than 0.2μs to support time division duplex (TDD) or burst-mode radio devices.