Analog Devices Inc. 108537-HMC498LC4

Overview

HMC498LC4 from Analog Devices is a GaAs PHEMT medium-power MMIC amplifier operating from 17 to 24 GHz, delivering 22 dB gain, +26 dBm saturated output power at 23% PAE with +5 V/250 mA supply, 4 dB noise figure, and +36 dBm output IP3 - enabling dual-role use as low-noise front-end or driver amplifier in millimeter-wave radios and test equipment.

For engineers reviewing the HMC498LC4 datasheet, HMC498LC4 pinout, HMC498LC4 application, or HMC498LC4 equivalent, key selection criteria include its 17–24 GHz bandwidth, 50 Ω matched RF I/Os, DC-blocked ports, RoHS-compliant 4×4 mm ceramic LCC package, and gate bias tuning requirement (Vgg = −0.8 V typical) for stable 250 mA quiescent current.

Technical Context

The HMC498LC4 employs a monolithic GaAs PHEMT process with three independent drain supply pins (Vdd1/Vdd2/Vdd3) and a single gate bias pin (Vgg) for precise Id control. Its internal matching eliminates external tuning components across 17–24 GHz.

RF input (Pin 3) and output (Pin 16) are AC-coupled and internally matched to 50 Ω; all unused terminals (1, 5–8, 10–14, 18, 20, 22, 24) are NC but require external RF/DC grounding per layout guidelines.

Key Specifications

Pinout & Package

Package: 24-terminal ceramic leadless chip carrier (LCC), 4.0 × 4.0 × 0.9 mm, alumina body, gold-over-nickel finish, MSL3, exposed thermal paddle requiring solder connection to ground plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar medium-power MMIC amplifier applications.

Compared with HMC498LC4, HMC460LC4 offers lower-frequency compatibility and reduced current draw but lacks 23–24 GHz support; QPA2211 extends upper frequency and power but demands revised thermal management and layout due to larger 5×5 mm QFN footprint and lid-based heat dissipation.

Availability

HMC498LC4 is available at Aetrix Electronics and suitable for point-to-point radios, VSAT terminals, and millimeter-wave test equipment requiring stable component supply, controlled thermal performance, and repeatable RF behavior across production lots.

Supply support for HMC498LC4 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, Inc. is a global semiconductor company specializing in high-performance analog, mixed-signal, and RF ICs for precision signal processing and connectivity.

The HMC498LC4 belongs to the Hittite Microwave (acquired by Analog Devices) MMIC amplifier product line, engineered for broadband millimeter-wave infrastructure where gain flatness, linearity, and thermal reliability are critical in compact SMT form factors.

FAQ

What is the recommended gate bias voltage for HMC498LC4 to achieve nominal operating current?

The HMC498LC4 requires Vgg adjustment between −2 V and 0 V to set Idd = 250 mA at +5 V supply. The typical value is −0.8 V, as specified in the "MMIC Amplifier Biasing Procedure" application note. External bypass capacitors (100 pF, 1000 pF, 2.2 µF) must be used on Pin 9 (Vgg) to ensure stability. Deviation beyond this range risks gain compression or thermal runaway in the HMC498LC4.

Does HMC498LC4 require external matching components for 50 Ω operation?

No, the HMC498LC4 features fully integrated 50 Ω input and output matching across 17–24 GHz. Both RFIN (Pin 3) and RFOUT (Pin 16) are AC-coupled and internally matched, eliminating the need for external baluns, stubs, or lumped-element networks. This simplifies PCB layout and improves repeatability in high-volume manufacturing of systems using the HMC498LC4.

What is the maximum allowable RF input power to avoid damage to HMC498LC4?

The absolute maximum RF input power for the HMC498LC4 is +10 dBm, as defined in the Absolute Maximum Ratings table. Exceeding this level - even briefly - may cause permanent degradation of the GaAs PHEMT cells. For reliable operation, input drive should be limited to ≤+3 dBm to maintain linear region performance and prevent gain compression or intermodulation distortion in the HMC498LC4.

How is thermal management implemented for HMC498LC4 in production assemblies?

Thermal management of the HMC498LC4 relies on soldering its exposed bottom paddle directly to a solid copper ground plane with ≥6 thermal vias connecting to internal ground layers. The specified thermal resistance is 55.6 °C/W (channel-to-ground). To sustain continuous operation at +85 °C ambient, the PCB must provide adequate copper area and airflow; the HMC498LC4 derates 18 mW/°C above 85 °C case temperature.

Is HMC498LC4 compatible with lead-free reflow processes?

Yes, the HMC498LC4 is RoHS-compliant and rated for lead-free reflow with a maximum peak temperature of 260 °C (MSL3). Its alumina package body and gold-over-nickel lead finish ensure robust solder joint integrity under JEDEC J-STD-020 conditions. Reflow profile must respect the 20-second duration above 217 °C and avoid thermal shock - critical for maintaining bond integrity in the HMC498LC4's GaAs die attach.