High linearity downconverting mixer covers 4-6-GHz RF frequency range

March 29, 2012 // By Paul Buckley
Linear Technology has released a 4 GHz to 6 GHz high dynamic range downconverting mixer. The LTC5544 mixer offers high linearity with 25.9 dBm IIP3 (Input Third-Order Intercept), high conversion gain of 7.4 dB owing to its integrated IF amplifier, and a noise figure of 11.3 dB.

The performance characteristics enable excellent dynamic range performance for both main receivers and digital pre-distortion receivers. Moreover, the LTC5544’s RF input can withstand strong interference signals without significantly degrading its noise figure, thus preserving receiver sensitivity and enhancing robustness. The LTC5544 operates on a single 3.3 V supply without compromising performance, while keeping power consumption to a minimum.

The LTC5544’s 6 GHz reach is ideally suited for wireless systems such as point-to-point broadband microwave links, 5 GHz license-free band WiMAX radios, satellite receivers, radar systems, avionics, public safety radios and RF test systems.

The LTC5544 incorporates an on-chip integrated high gain IF amplifier capable of supporting IF frequencies up to 1GHz. Also integrated are an LO buffer along with two RF balun transformers. They enable the RF and LO inputs to operate single-ended and with 50 Ω matching. The LO input requires only +2 dBm drive level. These features simplify design and require fewer external components, resulting in a smaller solution size.

The LTC5544 operates on a single 3.3 V supply, drawing 194 mA of current. The LTC5544 has a power-down feature with 0.6 µs turn-on and turn-off time, supporting Burst Mode operation or TDD (time division duplexed) systems. When disabled, the device consumes a maximum of 500 µA. The LTC5544 is offered in a 16-lead, 4 mm x 4 mm plastic QFN package and is available immediately from stock. Pricing starts at $8.50 each in 1,000 piece quantities.

More information about www.linear.com/product/LTC5544