“The RF frequency range has been greatly expanded, yet the size has been reduced.”

When asked what the most notable feature of the newly released double balance mixer is, this is what Manager Taehoon Jeong of Linear Technology Korea (CEO Hong Sa-gwak) said.

Frequency extension from 2GHz to 14GHz

The answer is simple, but it highlights the key point. The significant expansion of the frequency range is closely related to next-generation wireless network technologies with increased bandwidth. It reflects the trend of responding to ever-increasing Internet traffic. In complex and diverse wireless environments, mixers suited to higher and newer frequencies are needed.

The newly announced LTC5549 offers a wide RF frequency range extending from 2GHz to 14GHz, enabling operation as an upconverter or downconverter. The IF frequency range is 0.5GHz to 6GHz.

Additionally, the reduced device size (small 12-pin 3mm x 2mm plastic QFN package) is emphasized for the relative reason of peripheral component integration.
While most microwave mixers use discrete GaAs diodes or FETs in a hybrid module format, the LTC5549 integrates an on-chip LO buffer and microwave balun transformer using an advanced high-frequency SiGe BiCMOS process.

The monolithic die is mounted upside down directly into a plastic surface-mount package with a small 3 mm x 2 mm lead frame.

This eliminates the bond wires, significantly improving the microwave frequency performance of the device, without introducing any bond wire inductance. With minimal external circuitry, the inherently small package supports a very small solution footprint.

It offers exceptional linearity performance. The LTC5549 typically delivers an IIP3 of 22.3dBm, which is 4 to 6dB higher than traditional microwave-type mixers, explains Manager Jeong Tae-hoon.

These characteristics enable the LTC5549 to improve performance in a wide range of microwave applications, including microwave backhaul, LTE-Advanced (LTE-A) base stations in unlicensed frequency bands, satellite broadband radios, radar systems, X-band and Ku-band transceivers, test equipment, and satellite modems.