Analog Devices Inc. HMC329LC3B

Overview

HMC329LC3B from Analog Devices (formerly Hittite Microwave) is a GaAs MMIC double-balanced mixer operating from 24–32 GHz RF/LO and DC–8 GHz IF, delivering 12.5 dB typical conversion loss, +18 dBm input IP3, and 38 dB LO-to-RF isolation - ideal for millimeter-wave up/downconversion in point-to-point radios and test equipment.

For engineers reviewing the HMC329LC3B datasheet, HMC329LC3B pinout, HMC329LC3B application, or HMC329LC3B equivalent, this page delivers verified RF mixer specifications, validated 12-lead ceramic SMT package layout, real-world isolation and linearity data, and direct alternatives for 24–32 GHz system design.

Technical Context

The HMC329LC3B is a passive fundamental mixer with no DC bias required, leveraging optimized on-chip balun structures to achieve high LO-to-RF (38 dB typ.) and LO-to-IF (40 dB typ.) suppression across its full 24–32 GHz band. Its DC-coupled LO, RF, and IF ports enable seamless integration into broadband mmWave signal chains without external matching.

Designed for operation with LO drive ≥+9 dBm (optimal at +13 dBm), the HMC329LC3B supports both upconversion and downconversion modes with robust ESD protection (Class 1B, 500 V HBM) and operates over –40°C to +85°C ambient temperature.

Key Specifications

Pinout & Package

12-lead leadless ceramic SMT package (3×3 mm, 9 mm² body, alumina substrate, gold-over-nickel plating, MSL3 rating); ground paddle must be soldered to PCB RF ground per JEDEC standard.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar passive mmWave mixer applications.

Compared with HMC329LC3B, HMC1048LP3E trades 1 dB higher conversion loss for wider low-end RF coverage, while QM11020 offers +2 GHz upper-band extension but demands layout revision - neither is pin-compatible, and both require validation of LO drive, isolation, and thermal management in target systems.

Availability

HMC329LC3B is available at Aetrix Electronics and suitable for point-to-point radios, test equipment, and military radar sensors requiring stable component supply, RoHS-compliant SMT packaging, and guaranteed mmWave RF performance.

Supply support for HMC329LC3B 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 integrates its high-frequency RF portfolio into precision analog and mmWave solutions for communications, defense, and instrumentation markets.

The HMC329LC3B belongs to Hittite's legacy GaAs MMIC mixer family, engineered specifically for fundamental-mode passive mixing in 24–32 GHz infrastructure and test systems where bias-free operation and high isolation are critical.

FAQ

What is the recommended LO drive level for optimal performance of the HMC329LC3B?

The HMC329LC3B achieves best conversion loss and isolation at +13 dBm LO drive, with functional operation supported from +9 dBm to +15 dBm. Driving below +9 dBm increases conversion loss and degrades IP3; exceeding +15 dBm risks compression and long-term reliability. All electrical specs in the datasheet assume +13 dBm LO unless otherwise noted, and the HMC329LC3B must not be operated above +27 dBm LO per absolute maximum ratings.

Can the HMC329LC3B be used for DC-coupled IF operation, and what are the limits?

Yes, the HMC329LC3B supports true DC-coupled IF operation on Pin 5, but the IF port must not source or sink more than ±2 mA DC current - exceeding this limit causes non-function or permanent damage. For AC-coupled IF use, a series capacitor sized for the lowest IF frequency (e.g., 100 pF for 1 GHz) is recommended. The HMC329LC3B's DC–8 GHz IF bandwidth makes it uniquely suitable for baseband and wideband IF interfaces without external blocking components.

Does the HMC329LC3B require external matching components or bias circuitry?

No, the HMC329LC3B is a fully matched passive mixer: all RF, LO, and IF ports are internally DC-coupled and impedance-matched to 50 Ω across 24–32 GHz and DC–8 GHz. No external baluns, bias tees, or matching networks are required - the HMC329LC3B eliminates wire bonding and simplifies mmWave PCB layout by integrating optimized balun structures directly into the GaAs die.

What is the thermal management requirement for continuous operation of the HMC329LC3B?

The HMC329LC3B has a junction-to-ground-paddle thermal resistance of 170 °C/W and a max continuous power dissipation of 382 mW at 85 °C ambient. To maintain channel temperature ≤150 °C, the exposed ground paddle must be soldered to a thermally robust PCB ground plane with ≥6 thermal vias (0.3 mm diameter) connecting to inner/outer ground layers. The HMC329LC3B's ceramic package and paddle design require explicit thermal via placement per the outline drawing - insufficient grounding raises junction temperature and degrades conversion loss and IP3.

Is the HMC329LC3B pin-compatible with other Hittite mixer variants like HMC329LP3E or HMC1048LP3E?

No, the HMC329LC3B is not pin-compatible with HMC329LP3E (16-lead LCC) or HMC1048LP3E (12-lead but different pin assignment). While all three use 3×3 mm ceramic packages, the HMC329LC3B's pinout - including GND on Pins 1/3/4/6/7/9 and N/C on Pins 10/11/12 - is unique to this variant. Substituting any of these parts requires PCB redesign. The HMC329LC3B datasheet explicitly defines its 12-pin function map and prohibits assumptions of mechanical or electrical interchangeability.