Analog Devices Inc. HMC404-SX

Overview

HMC404-SX from Analog Devices (formerly Hittite Microwave) is a GaAs MMIC sub-harmonically pumped image rejection mixer (IRM) designed for RF-to-IF conversion in 26–33 GHz microwave systems. It integrates an on-chip LO amplifier requiring only +2 dBm drive, delivers ≥22 dB image rejection via monolithic 90° hybrid, and operates with DC–3 GHz IF bandwidth - enabling high-fidelity up/downconversion in point-to-point radios and satellite transceivers.

For engineers reviewing the HMC404-SX datasheet, HMC404-SX pinout, HMC404-SX application, or HMC404-SX equivalent, this page provides verified technical context, validated pin functions, confirmed RF/LO/IF frequency ranges, real-world isolation metrics (2LO-to-RF/IF ≥35 dB), and two rigorously cross-referenced alternative IRMs for 26–33 GHz band migration.

Technical Context

The HMC404-SX implements a true I/Q architecture using monolithic GaAs PHEMT technology, with integrated 90° hybrid coupler and two-stage LO amplifier biased at +4 V. Its sub-harmonic (x2) pumping enables LO operation at half the RF frequency (13–16.5 GHz), relaxing LO source requirements while maintaining >22 dB image rejection across 26–33 GHz.

It operates as either upconverter or downconverter with DC-coupled IF1/IF2 ports supporting baseband-to-3 GHz IF, AC-coupled RF/LO ports matched to 50 Ω, and requires external 100–330 pF RF bypass capacitor on Vdd. Thermal operation spans −55°C to +85°C with 238 mW max dissipation at 85°C.

Key Specifications

Pinout & Package

The HMC404-SX is supplied as a bare die in GP-2 packaging format, measuring 1.90 × 1.25 mm with 0.102 mm thickness and gold metallized bond pads. Backside is grounded; no package substrate or leadframe is included.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar image rejection mixer applications.

Compared with HMC404-SX, HMC1048-SX trades integrated LO amplification for broader bandwidth and higher linearity, while QM11024 offers lower unit cost at the expense of 4 dB image rejection and +14 mA higher supply current - making HMC404-SX optimal for space-constrained, LO-power-sensitive 26–33 GHz radios requiring ≥22 dB image suppression.

Availability

HMC404-SX is available at Aetrix Electronics and suitable for 26–33 GHz microwave radios, satellite communication transceivers, and millimeter-wave test equipment requiring stable component supply, traceable sourcing, and long-term lifecycle support.

Supply support for HMC404-SX includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices acquired Hittite Microwave in 2014 and maintains its high-frequency RF portfolio, specializing in GaAs, GaN, and SiGe MMIC solutions for defense, aerospace, and communications infrastructure.

The HMC404-SX belongs to Analog Devices' legacy Hittite IRM product line, engineered specifically for compact, high-rejection I/Q mixing in E-band and Ka-band wireless infrastructure and instrumentation.

FAQ

What is the recommended LO drive level for optimal performance of the HMC404-SX?

The HMC404-SX is specified for +2 dBm nominal LO drive at 13–16.5 GHz with Vdd = +4 V. Performance data (conversion gain, image rejection, IP3) is characterized at this level. Increasing LO drive to +4 dBm improves conversion gain by ~2 dB but degrades IP3 by ~3 dB; exceeding +6 dBm risks compression and distortion. The integrated LO amplifier eliminates need for external driver stages when using +2 dBm sources.

Can the HMC404-SX operate as both upconverter and downconverter?

Yes, the HMC404-SX supports bidirectional operation. As a downconverter, RF (26–33 GHz) is applied to Pin 3, LO (13–16.5 GHz) to Pin 1, and I/Q IF outputs appear on Pins 4 and 5. As an upconverter, IF signals are injected into Pins 4 and 5, LO applied to Pin 1, and RF output appears on Pin 3. All electrical specifications in the datasheet are measured in downconverter mode unless otherwise noted.

What is the maximum allowable DC current on the IF1 and IF2 pins of the HMC404-SX?

The HMC404-SX IF1 and IF2 pins are DC-coupled and rated for ±3 mA maximum sink/source current when operating to DC. Exceeding this limit risks die malfunction or permanent failure. For AC-coupled IF operation (e.g., >100 MHz), external series capacitors must be used - values selected to pass the full IF band (DC–3 GHz) without excessive insertion loss or group delay variation.

Does the HMC404-SX require external matching networks on RF or LO ports?

No - the HMC404-SX RF (Pin 3) and LO (Pin 1) ports are internally matched to 50 Ω and AC-coupled. No external matching components are needed for standard 50 Ω system interfaces. However, the Vdd (Pin 2) line requires a local 100–330 pF RF bypass capacitor placed within 0.762 mm of the pad to ensure stable LO amplifier operation and minimize supply noise coupling.

What is the operating temperature range and thermal derating specification for the HMC404-SX?

The HMC404-SX operates from −55°C to +85°C ambient. Maximum continuous power dissipation is 238 mW at +85°C, with linear derating of 2.64 mW/°C above that temperature. At +105°C ambient, max dissipation drops to 188 mW. Die mounting must use thermally conductive methods (AuSn eutectic or conductive epoxy) to ground plane to maintain junction temperature within safe limits under full RF/LO drive conditions.