Analog Devices Inc. HMC344LH5TR

Overview

HMC344LH5TR from Analog Devices (formerly Hittite Microwave) is a GaAs MMIC SP4T non-reflective RF switch operating from DC to 12 GHz, delivering 1.8 dB typical insertion loss and 42 dB isolation at 6 GHz with integrated 2:4 TTL decoder logic. It uses negative control voltages (0/–5 V), requires –5 V fixed bias, and supports surface-mount manufacturing for high-reliability RF signal routing in military radar front-ends.

For engineers reviewing the HMC344LH5TR datasheet, HMC344LH5TR pinout, HMC344LH5TR application, or HMC344LH5TR equivalent, key selection criteria include broadband DC–12 GHz operation, non-reflective architecture enabling stable impedance during state transitions, –40°C to +85°C operating temperature range, and hermetic ceramic SMT package compatibility with MIL-PRF-38535 Class B/S screening.

Technical Context

The HMC344LH5TR implements a monolithic GaAs MESFET SP4T switch topology with on-die binary decoder, reducing external control lines from four to two (A/B inputs). Its non-reflective design maintains 50 Ω match in both "on" and "off" states across DC–12 GHz, minimizing signal reflections in sensitive RF paths.

It operates with Vee = –5 V ±10%, draws 3.0 mA typical supply current, and accepts TTL/CMOS-compatible control logic via external level-shifting circuitry. Switching speed is characterized by 35 ns rise/fall time and 75 ns turn-on/turn-off delay, supporting fast RF path reconfiguration in test instrumentation and ECM systems.

Key Specifications

Pinout & Package

Package: Hermetic ceramic SMT leadless package, 25 mm² footprint (5.0 × 5.0 mm), gold-plated Kovar base, RoHS-compliant, MIL-PRF-38535 Class B/S screening available.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar SP4T RF switch applications.

Compared with HMC344LH5TR, HMC349ALP4E trades non-reflective operation for lower loss and higher isolation margin at lower frequencies, while QM11036 offers simplified positive-control interface at the expense of bandwidth, ruggedness, and impedance stability-making HMC344LH5TR uniquely suited for broadband, high-reliability, reflection-sensitive RF systems.

Availability

HMC344LH5TR is available at Aetrix Electronics and suitable for military radar front-ends, space-based communication payloads, and automated test instrumentation requiring stable component supply, long-term obsolescence management, and traceable sourcing.

Supply support for HMC344LH5TR 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/Microwave portfolio into precision analog and RF solutions for defense, aerospace, and communications.

The HMC344LH5TR belongs to Hittite's legacy GaAs MMIC SPnT switch product line, engineered specifically for broadband, non-reflective RF signal routing in mission-critical radar, EW, and instrumentation systems.

FAQ

What is the control voltage requirement for HMC344LH5TR?

The HMC344LH5TR requires negative control logic: A and B inputs accept 0 V (high) and –5 V (low) levels, referenced to Vee (–5 V). External level-shifting circuitry is needed to interface with standard TTL/CMOS positive logic families. The HMC344LH5TR datasheet specifies control voltage tolerance as Vee –0.5 V to +1.0 Vdc, ensuring robust noise margin in high-EMI environments.

Does HMC344LH5TR require external DC blocking capacitors?

Yes, HMC344LH5TR RF ports (RFC, RF1–RF4) are DC-coupled and matched to 50 Ω, so external DC blocking capacitors are mandatory if the connected RF line has non-zero DC potential. This prevents bias disruption and ensures proper impedance matching. The HMC344LH5TR evaluation board (110758) uses 10 kΩ pF 0603 capacitors at each RF port for this purpose.

What is the thermal resistance and power dissipation limit of HMC344LH5TR?

HMC344LH5TR has two thermal resistance values: 157 °C/W for the insertion loss path and 264 °C/W for the terminated path. Its maximum continuous power dissipation is 0.42 W at 85 °C (derating 6.4 mW/°C above), and 0.25 W for terminated paths (derating 3.8 mW/°C). These limits ensure safe operation under sustained RF load in compact RF modules.

Is HMC344LH5TR suitable for space applications?

Yes, HMC344LH5TR is offered with MIL-PRF-38535 Class B or S screening, including burn-in, temperature cycling, and hermeticity testing. Its ceramic-Kovar hermetic package, –40°C to +85°C operating range, and ESD Class 1A rating make it suitable for LEO and GEO satellite communication payloads where radiation tolerance and long-term reliability are critical. The HMC344LH5TR has been deployed in flight-proven space systems.

How does the integrated decoder in HMC344LH5TR reduce system complexity?

The HMC344LH5TR integrates a 2:4 binary decoder, allowing full SP4T selection using only two control lines (A and B) instead of four. This eliminates external logic gates, reduces GPIO usage on host controllers, and minimizes PCB routing congestion-especially valuable in dense RF modules like radar T/R arrays. The HMC344LH5TR truth table defines RFC→RF1 through RFC→RF4 mapping unambiguously.