Analog Devices Inc. HMC620LC4

Overview

HMC620LC4 from Analog Devices (formerly Hittite Microwave) is a GaAs MMIC I/Q mixer designed for RF front-end signal translation in 3–7 GHz systems, delivering 9 dB typical conversion loss, 32 dB image rejection, and +22 dBm input IP3 as an Image Reject Mixer (IRM). It operates with DC–3.5 GHz IF bandwidth and supports both downconversion and single-sideband upconversion in point-to-point radio and WiMAX infrastructure.

For engineers reviewing the HMC620LC4 datasheet, HMC620LC4 pinout, HMC620LC4 application, or HMC620LC4 equivalent, this device is selected for high-isolation, wide-IF, quadrature-based RF systems requiring stable amplitude/phase balance (±0.3 dB / ±3°), RoHS-compliant SMT integration, and operation across –55°C to +85°C industrial temperature range.

Technical Context

The HMC620LC4 integrates two double-balanced GaAs MESFET mixer cells with an on-die 90° hybrid to enable image-reject functionality without external hybrids. Its architecture supports IRM mode with external IF 90° hybrid or direct USB upconversion using internal phase splitting.

It features DC-coupled 50 Ω-matched RF and LO ports, differential IF outputs (IF1/IF2), and requires all ground pins plus the exposed paddle to be soldered to PCB RF ground. Absolute maximum ratings include +27 dBm LO drive and +20 dBm RF/IF input.

Key Specifications

Pinout & Package

24-lead leadless ceramic SMT package (4×4 mm, 16 mm²), alumina body with gold-over-nickel plating, MSL3 rating, and exposed thermal paddle requiring solder connection to PCB ground plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar I/Q mixer applications.

Compared with HMC1048LP4E and ADL5375-05, the HMC620LC4 delivers superior image rejection and lower conversion loss within its native 3–7 GHz band, while its monolithic hybrid eliminates external component count-making it optimal for space-constrained, high-performance receive chains in licensed microwave systems.

Availability

HMC620LC4 is available at Aetrix Electronics and suitable for point-to-point radio, WiMAX infrastructure, and VSAT terminal designs requiring stable component supply, long-lifecycle support, and guaranteed RoHS-compliant sourcing.

Supply support for HMC620LC4 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 ICs for communications, defense, and instrumentation markets.

The HMC620LC4 belongs to Hittite's legacy GaAs MMIC I/Q mixer product line, engineered specifically for compact, high-isolation, wide-IF RF front-ends in licensed wireless infrastructure.

FAQ

What is the recommended LO drive level for optimal performance of the HMC620LC4?

The HMC620LC4 achieves best image rejection and conversion loss at +15 dBm LO drive, as verified in electrical specifications tables. Operating at +13 dBm or +17 dBm degrades image rejection by up to 5 dB and increases conversion loss by ~0.5 dB. The absolute maximum LO input is +27 dBm, but sustained operation above +17 dBm risks accelerated aging.

Can the HMC620LC4 be used as a single-sideband upconverter without external components?

Yes-the HMC620LC4 supports SSB upconversion internally using its integrated 90° hybrid; however, external IF 90° hybrid is required for IRM operation. For upconversion, RF and LO ports serve as inputs, and IF1/IF2 deliver the USB output. No external balun or hybrid is needed for basic SSB generation, though IF filtering may be required for spurious suppression.

What is the thermal management requirement for continuous operation of the HMC620LC4?

The HMC620LC4 has a thermal resistance of 112 °C/W (channel to die bottom) and maximum channel temperature of 150 °C. To maintain safe operation at full 579 mW dissipation, the PCB must provide low-thermal-resistance grounding via the exposed paddle and ≥6 thermal vias to inner ground planes. Derating begins at 85 °C ambient, reducing power by 8.93 mW per °C above that point.

Are the IF1 and IF2 outputs of the HMC620LC4 differential or single-ended?

The IF1 and IF2 outputs are single-ended, DC-coupled ports delivering complementary I and Q baseband or IF signals. They are not true differential pairs; each requires individual 50 Ω termination. DC blocking capacitors are optional unless operating down to DC, in which case current must remain within ±3 mA to prevent damage.

Does the HMC620LC4 require external biasing or is it self-biased?

The HMC620LC4 is fully self-biased-no external DC bias networks, resistors, or voltage supplies are needed. All active devices are internally biased via on-chip circuitry. Only RF, LO, and IF connections plus robust RF grounding (pins 3,5,12,14,16 and paddle) are required for operation.