Replace LTC5548/5549 with GX5548/5549 Broadband Mixers for RF Test and Measurement Instruments

RF test instruments mainly include spectrum analyzers, signal generators, network analyzers, and power probes. They are used for design verification and production testing of RF systems such as wireless communications, radar, satellite, Bluetooth, and 5G/6G. In the frequency conversion chain of RF test instruments, the mixer‘s ultra-wideband continuous frequency coverage and high-linearity, low-distortion characteristics are core technical requirements. This article recommends a domestically produced passive double-balanced broadband mixer.

The GX5548/5549 broadband mixer operates over a wide frequency range of 2 GHz to 15 GHz, covering mainstream commercial and industrial microwave backhaul bands. It is suitable for multi-scenario testing such as 5G millimeter wave, microwave backhaul, and C/X/Ku-band radar, meeting the needs of various RF test instruments. The IF port is a differential interface, and an appropriate external balun can be selected according to the actual IF frequency to convert it to a single-ended signal. This chip is especially suitable for scenarios where the IF frequency is below 500 MHz. The differential port can also be directly cascaded with a differential filter or a differential IF amplifier.

The GX5548/5549 has a very wide operating frequency range: RF frequency from 2 to 15 GHz, LO frequency from 1 to 14 GHz, and IF frequency from 0.5 to 6 GHz. Each port has ultra-wideband characteristics. The chip integrates an LO amplifier, so during normal operation, only a typical LO power of 0 dBm is required to drive the mixer. It also integrates an optional LO frequency doubler, which can halve the required LO frequency when needed, reducing the demand on the source.

GX5548/5549 Product Advantages:

PIN TO PIN replacement for LTC5548/5549

RF, LO, and IF ports are all broadband and multi-purpose

CMOS process, low-cost mass production

Downconversion input P-1dB 15 dBm, IIP3 26 dBm;

Upconversion input P-1dB 14 dBm, IIP3 24 dBm

Small size, suitable for miniaturized design

Integrated LO amplifier chain

Integrated optional LO frequency doubler

Broadband RF, LO, and IF operating frequencies

Single-ended RF and LO ports matched to 50 Ω

Differential IF port

Supports ultra-low-frequency IF applications

High linearity (input P-1dB and IIP3)

Small QFN package, size 3 mm x 2 mm