Analog Devices Inc. HMC231G7

Overview

HMC231G7 from Analog Devices (formerly Hittite Microwave) is a GaAs MMIC SPST switch in a hermetic surface-mount package, operating from DC to 6 GHz with >55 dB isolation at 2 GHz and 42 dB at 6 GHz, 2.0 dB typical insertion loss at 6 GHz, and non-reflective 50 Ω termination in OFF state-used in microwave radio transceivers and radar front-ends.

For engineers reviewing the HMC231G7 datasheet, HMC231G7 pinout, HMC231G7 application, or HMC231G7 equivalent, key selection criteria include isolation vs. frequency, complementary -5/0 V control logic, DC-coupled 50 Ω RF ports, thermal resistance (94 °C/W), and Class 1A ESD rating for high-reliability RF switching.

Technical Context

The HMC231G7 implements a non-reflective GaAs MESFET architecture with complementary negative-voltage control (A/B pins at -5 V / 0 V), enabling true 50 Ω termination on both RF1 and RF2 in OFF state. It requires no external bias supply and supports DC-coupled operation with blocking capacitors only when RF line DC potential deviates from 0 V.

Switching is characterized by 3 ns rise/fall time and 6 ns ON/OFF delay across DC–6 GHz. Absolute maximum ratings include +30 dBm RF input power at +50 °C, -40 °C to +85 °C operating temperature, and 150 °C channel temperature limit-enabling deployment in space-qualified and military-grade systems.

Key Specifications

Pinout & Package

Hermetic surface-mount package with white alumina (92%) body, thick-film tungsten traces, Kovar™ leads/base/cover, and 50 µin gold over 50 µin nickel plating. Ground leads (pins 2, 4, 7) and bottom paddle must be soldered to PCB RF ground per RF design best practices.

Key Features

Applications

Equivalent & Alternatives

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

Compared with HMC231G7, HMC547LP3E extends usable bandwidth and improves isolation above 6 GHz but adds complexity with bias and logic translation; QM11036 reduces cost and simplifies control at the expense of hermetic reliability, linearity (42 dBm IP3), and isolation margin.

Availability

HMC231G7 is available at Aetrix Electronics and suitable for telecom infrastructure, microwave radio, and military radar applications requiring stable component supply, long-lifecycle support, and traceable sourcing of obsolete-qualified RF components.

Supply support for HMC231G7 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-performance RF/Microwave product portfolio, emphasizing precision, linearity, and reliability for demanding defense and communications systems.

The HMC231G7 belongs to Hittite's legacy GaAs MMIC SPST switch family, designed specifically for high-isolation, DC–6 GHz RF path control in mission-critical aerospace, radar, and test instrumentation applications.

FAQ

What is the control voltage logic scheme used by the HMC231G7?

The HMC231G7 uses complementary negative-voltage logic: pin A = -5 V / 0 V and pin B = 0 V / -5 V. When A is HIGH (-5 V) and B is LOW (0 V), the switch is OFF; when A is LOW (0 V) and B is HIGH (-5 V), it is ON. No external bias supply is needed, and the control interface draws only microamps.

Does the HMC231G7 require external DC blocking capacitors on its RF ports?

Yes, the HMC231G7 RF1 and RF2 ports are DC-coupled and internally matched to 50 Ω. External blocking capacitors are required if the connected RF line has a DC potential other than 0 V. This prevents unintended biasing of the GaAs MESFET core and ensures specified RF performance across DC–6 GHz.

What is the thermal resistance and maximum junction temperature specification for the HMC231G7?

The HMC231G7 has a junction-to-lead thermal resistance (R_TH) of 94 °C/W and a maximum channel temperature of 150 °C. Its operating temperature range is -40 °C to +85 °C. Proper PCB grounding of all GND pins (2, 4, 7) and the bottom paddle is essential to maintain thermal performance in high-power applications.

Can the HMC231G7 be used in space-grade applications?

Yes, the HMC231G7's hermetic ceramic package, Class 1A ESD rating, -40 °C to +85 °C operating range, and proven reliability in radar and ECM systems make it suitable for space-qualified designs. However, users must perform full radiation testing and qualification per mission-specific requirements, as Analog Devices does not provide radiation-hardened certification out-of-box.

What is the recommended PCB layout practice for the HMC231G7 ground connections?

All ground pins (2, 4, 7) and the exposed bottom paddle of the HMC231G7 must be soldered directly to a low-inductance RF ground plane using multiple vias. The evaluation PCB (P/N 107744) uses Rogers 4350 substrate with 50 Ω controlled-impedance RF traces-this layout is mandatory to achieve specified isolation, return loss, and thermal performance.