Additionally, passive mixers require high LO (local oscillator) drive to reach their claimed IIP3. The LTC5551 has an integrated LO buffer requiring only 0dBm drive level, hence external circuitry and costs are minimized. And with the elimination of a high power LO signal in the users’ receiver, it substantially reduces a potential source of undesirable radiation, thus simplifying filtering and RF shielding requirements.
The LTC5551 ensures robust radio performance with its high 1dB compression point of +18dBm. Both the RF and LO inputs have integrated balun transformers, further reducing cost and external components while simplifying the design task. The mixer is powered from a single 3.3V supply with current consumption of 204mA, delivering its high performance with exceptionally low power. If needed, the mixer also has a low power mode controlled via the ISEL pin. In this mode, current consumption drops by 30% to 142mA, trading off the IIP3 slightly to +29.3dBm.
The superior performance of this mixer is ideally suited for a wide range of mission-critical, high performance applications that are exposed to strong interference sources such as multi-carrier GSM, 4G LTE and LTE-Advanced multimode basestations, point-to-point backhauls, military communications, wireless repeaters, public safety radios, VHF/UHF/white-space broadcast receivers, radar and avionics.
The mixer can be conveniently shut down with an enable control pin. When disabled, the IC draws a maximum of 100µA standby current. The device turns on and off in 500ns, suitable for burst-mode receivers. The LTC5551 is specified for operation from -40°C to 105°C case temperature. The mixer’s minimum external circuits and its 16-lead, 4mm x 4mm QFN package provide a highly compact solution footprint. The LTC5551 is priced starting at $7.25 each in 1,000-piece quantities. Production quantities are available immediately