Analog Devices Inc. 122789-HMC504LC4B

Overview

HMC504LC4B from Analog Devices is a GaAs HEMT MMIC low-noise amplifier operating from 14 to 27 GHz, delivering 19 dB small-signal gain, 2.2 dB noise figure at 20 GHz, +17 dBm P1dB output power, and +26 dBm output IP3 while drawing 90 mA from a +4 V supply. It is DC-blocked and internally 50 Ω matched at input and output, enabling direct integration into microwave radio front-ends.

For engineers reviewing the HMC504LC4B datasheet, HMC504LC4B pinout, HMC504LC4B application, or HMC504LC4B equivalent, key selection criteria include its wideband LNA performance across Ka-band, thermal stability over –40°C to +85°C, gate bias control (Vgg = –1.7 to 0 V), exposed paddle thermal management, and compatibility with high-frequency PCB layouts requiring 2.92 mm connectors and RF-grade substrates.

Technical Context

The HMC504LC4B employs a monolithic GaAs HEMT process to achieve broadband low-noise amplification without external matching networks. Its internal 50 Ω terminations eliminate discrete input/output matching components, and the DC-blocked I/Os simplify system-level integration in transmit/receive chains.

It operates with fixed +4 V drain supply and adjustable gate voltage (Vgg) to set quiescent current at 90 mA. The exposed metal paddle provides a low-thermal-resistance path (50 °C/W) to ground, supporting continuous operation up to +85 °C ambient with proper heatsinking.

Key Specifications

Pinout & Package

Package: 24-terminal ceramic leadless chip carrier (LCC), 4×4 mm body (16 mm²), alumina substrate, gold-over-nickel finish, MSL3 rating, exposed thermal paddle on bottom.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-noise amplifier applications.

Compared with HMC504LC4B, the HMC-ALH476 offers identical RF performance but demands advanced packaging expertise, while the QPL9547 trades 2 GHz bandwidth and 0.3 dB NF for lower cost and smaller footprint in commercial deployments below 25 GHz.

Availability

HMC504LC4B is available at Aetrix Electronics and suitable for point-to-point radios, military communications systems, and test instrumentation requiring stable component supply, traceable lot history, and long-term obsolescence management.

Supply support for HMC504LC4B 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 leader in high-performance analog, mixed-signal, and RF technologies, serving aerospace, defense, communications, and industrial markets with precision signal processing solutions.

The HMC504LC4B belongs to Analog Devices' Hittite Microwave MMIC product line, engineered specifically for Ka-band infrastructure applications demanding ultra-low noise, high linearity, and ruggedized SMT packaging.

FAQ

What is the recommended gate bias voltage range for stable operation of the HMC504LC4B?

The HMC504LC4B requires gate bias voltage (Vgg) between –1.7 V and 0 V to achieve the specified 90 mA supply current at +4 V drain voltage. Typical Vgg is –0.3 V. Operation outside this range risks gain instability or device damage. Always verify Idd with a current probe during prototype tuning, and refer to the "MMIC Amplifier Biasing Procedure" application note for step-by-step setup guidance specific to HMC504LC4B.

Does the HMC504LC4B require external input or output matching components?

No, the HMC504LC4B does not require external input or output matching components. Its RF ports are internally DC-blocked and matched to 50 Ω across 14–27 GHz, as confirmed by S-parameter data in the official datasheet. This eliminates discrete matching networks, reduces insertion loss, and simplifies PCB layout-critical for Ka-band designs where parasitic effects dominate. External DC blocking remains unnecessary unless system-level DC coupling is required elsewhere in the signal chain.

How should the exposed thermal paddle of the HMC504LC4B be connected on the PCB?

The exposed thermal paddle on the bottom of the HMC504LC4B must be soldered directly to a solid copper ground plane using a grid of ≥9 thermal vias (0.3 mm diameter, spaced ≤0.8 mm apart). These vias must connect to inner and bottom ground layers to achieve ≤2.5 °C/W effective thermal resistance. Inadequate paddle connection causes junction temperature rise beyond 180 °C, triggering permanent degradation. Evaluation PCB 122789 demonstrates the validated footprint and stencil design required for HMC504LC4B.

Can the HMC504LC4B be used as a local oscillator driver in mixer applications?

Yes, the HMC504LC4B is explicitly qualified as an LO driver for balanced, I/Q, and image-reject mixers due to its +17 dBm P1dB output power and +26 dBm output IP3. At 21 GHz, it delivers sufficient saturated power and harmonic suppression to drive passive or active mixers without compression-induced distortion. Its 50 Ω matched output ensures minimal reflection into sensitive LO ports, preserving mixer conversion loss and port isolation-key for HMC504LC4B deployment in high-performance transceivers.

What is the maximum RF input power the HMC504LC4B can tolerate without damage?

The absolute maximum RF input power for the HMC504LC4B is +6 dBm, per the Absolute Maximum Ratings table. Exceeding this level-even briefly-risks permanent gate oxide damage or HEMT channel degradation. For safe operation, limit input power to ≤–5 dBm during normal amplification, and use external attenuators or limiter diodes if transient overdrive is possible. This specification applies regardless of bias condition or temperature, and is independent of the +4.5 V drain voltage limit.