Analog Devices Inc. 130602-HMC942LP4E

Overview

HMC942LP4E from Analog Devices (formerly Hittite Microwave) is a GaAs pHEMT-based x2 active frequency multiplier IC designed for LO generation in millimeter-wave systems. It delivers +21 dBm typical output power across 25–31 GHz output range when driven by +4 dBm input at 12.5–15.5 GHz, with >45 dBc fundamental (Fo) isolation and 24-lead 4×4 mm SMT package. Ideal for VSAT radios and SONET OC-192 clock synthesis.

For engineers reviewing the HMC942LP4E datasheet, HMC942LP4E pinout, HMC942LP4E application, or HMC942LP4E equivalent, key selection criteria include its 25–31 GHz output bandwidth, +4.5 V single-supply operation, 214 mA supply current, Fo isolation >45 dBc, and RoHS-compliant 4×4 mm leadless package - all critical for high-frequency LO chain design and space-constrained RF front-ends.

Technical Context

The HMC942LP4E implements a broadband GaAs pHEMT MMIC architecture optimized for second-harmonic (2Fo) generation with minimal fundamental and third-harmonic content. Its internal bias network enables stable operation from −40°C to +85°C using only a single +4.5 V supply, with integrated thermal management via exposed ground paddle.

Input is DC-coupled and 50 Ω matched; output is AC-coupled and 50 Ω matched. All non-functional pins (2, 8–11, 17, 20–21, 23) are internally unconnected but require grounding per RF layout best practices. Fo isolation exceeds 45 dBc at 19 GHz, enabling clean LO multiplication without external filtering in many Pt-to-Pt radio architectures.

Key Specifications

Pinout & Package

Package: 24-lead, 4×4 mm leadless plastic SMT (LP4E) with exposed thermal ground paddle. RoHS-compliant, matte Sn finish, MSL1 rating, max reflow 260°C.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar active frequency multiplier applications.

Compared with HMC1084LP4E and QPL9057, the HMC942LP4E offers superior output power (+21 dBm) and Fo rejection (>45 dBc) within its 12.5–15.5 GHz input window, making it the preferred choice for high-performance Ka/E-band LO generation where spectral purity and drive capability are critical.

Availability

HMC942LP4E is available at Aetrix Electronics and suitable for point-to-point radios, SONET OC-192 clock generation, and millimeter-wave test instrumentation requiring stable component supply across extended temperature ranges and high-frequency performance consistency.

Supply support for HMC942LP4E 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 microwave/mmWave ICs for defense, communications, and instrumentation markets.

The HMC942LP4E belongs to Hittite's active frequency multiplier product line, engineered specifically for high-efficiency, high-isolation LO synthesis in Ka- and E-band wireless infrastructure and aerospace systems.

FAQ

What is the recommended input drive level for optimal performance of the HMC942LP4E?

The HMC942LP4E achieves best output power and Fo isolation when driven with +4 dBm input power. Performance remains functional across +0 to +6 dBm, but output power peaks near +4 dBm and Fo isolation degrades slightly above +5 dBm due to compression effects. For HMC942LP4E, maintaining drive within this window ensures stable 25–31 GHz output with minimal distortion and thermal stress.

Does the HMC942LP4E require external DC blocking capacitors on RFIN or RFOUT?

No - the HMC942LP4E features internal DC coupling on RFIN and internal AC coupling on RFOUT. An external DC blocking capacitor is unnecessary on RFIN, and RFOUT already includes an integrated blocking capacitor. Adding external ones may degrade broadband match and cause passband ripple. The HMC942LP4E datasheet confirms this configuration for all specified operating conditions.

Can the HMC942LP4E operate from a +5.0 V supply?

Yes - the HMC942LP4E supports +4.0 to +5.0 V operation per absolute maximum ratings and typical supply current data. At +5.0 V, supply current rises to 217 mA and output power increases marginally, but Fo isolation decreases ~2–3 dBc. For HMC942LP4E, +4.5 V is the recommended nominal supply to balance efficiency, isolation, and thermal dissipation.

What is the thermal resistance (θ_JA) of the HMC942LP4E package?

The HMC942LP4E has a channel-to-ground-paddle thermal resistance of 60 °C/W. When mounted on a 4-layer PCB with ≥6 thermal vias under the exposed paddle and connected to a solid ground plane, junction-to-ambient resistance typically falls between 45–55 °C/W. This allows the HMC942LP4E to sustain continuous operation at +85°C ambient with proper board-level thermal design.

Is the HMC942LP4E pin-compatible with other Hittite LP4E-packaged multipliers like HMC1084LP4E?

Yes - the HMC942LP4E shares identical 24-lead 4×4 mm LP4E footprint, pin numbering, and ground/pad layout with HMC1084LP4E and HMC1150LP4E. All three use the same mechanical outline, pad dimensions, and thermal paddle configuration. However, pin functions differ: HMC942LP4E uses Pin 22 for Vdd, while HMC1084LP4E uses Pin 23 - requiring schematic review before drop-in replacement.