GXSC Broadband Mixer Replaces LTC5552/LTC5553 in Signal Analyzers

Signal analyzers are used to capture, decode, and analyze complex digital and analog signals, and are critical for high-precision applications such as the development of high-definition video transmission, high-speed data communication, and radar signal processing. High-frequency microwave signals received by the equipment undergo impedance matching and low-noise amplification before being fed into a mixer to downconvert the high-frequency signal, shifting the microwave RF signal to the low-frequency intermediate frequency (IF) range. After precise IF filtering and gain adjustment, the signal is sent to a high-speed ADC for digital sampling, and finally, the back-end FPGA/DSP performs FFT spectrum analysis.

Modern microwave signal analyzers must cover mainstream microwave, Ku-band satellite, and 5G millimeter-wave bands, requiring mixers with ultra-wide RF operating bandwidths. The GXSC broadband mixer supports the 3 GHz to 20 GHz frequency range, enabling continuous frequency conversion coverage across the entire microwave spectrum. The chip integrates an internal RF balun for greater convenience and also incorporates an LO amplification chain supporting local oscillator (LO) operating frequencies from 1 to 20 GHz, with a typical LO power requirement of only 0 dBm. The IF port features an on-chip balun and provides a single-ended interface, facilitating cascaded use of IF ports.

The GXSC broadband mixer features a wide operating frequency range: RF frequency from 3 GHz to 20 GHz, LO frequency from 1 GHz to 20 GHz, and IF frequency from 0.5 GHz to 9 GHz, with all ports exhibiting ultra-wideband characteristics. The chip also integrates an LO amplifier; therefore, during normal operation, only a typical LO power of 0 dBm is required to drive the mixer. The chip is powered by a single 3.3 V supply, making it simple and easy to use.

Key Performance Specifications of the GXSC Broadband Mixer:

 RF operating bandwidth: 3–20 GHz

 LO operating bandwidth: 1–20 GHz

 IF operating bandwidth: DC–6 GHz

 Down-conversion input P-1dB: 16 dBm (typical)

 Up-conversion input P-1dB: 13 dBm (typical)

 Downconversion IIP3: 27 dBm (typical)

Upconversion IIP3: 23 dBm (typical)

Downconversion loss: 10 dB (typical)

Upconversion loss: 8 dB (typical)

Required LO power: 0 dBm (typical)

Voltage/Current: 3.3 V/146 mA (typical)

 Chip Size: 3 mm × 2 mm

Operating Temperature Range: –55°C to 125°C

Supports QFN packaging; pin-to-pin replacement for the LTC5552/LTC5553