Analog Devices Inc. 106582-HMC365G8

Overview

The HMC365G8 from Analog Devices (formerly Hittite Microwave) is a GaAs HBT MMIC static frequency divider with divide-by-4 functionality, operating from DC (square-wave input) to 13 GHz input frequency, delivering 7 dBm output power at +5 V supply, and achieving -151 dBc/Hz SSB phase noise at 100 kHz offset - used in high-performance prescaler stages for Ku-band PLL systems.

For engineers reviewing the HMC365G8 datasheet, HMC365G8 pinout, HMC365G8 application, or HMC365G8 equivalent, this device supports critical RF timing functions in space-grade and military radios where low additive phase noise, wideband input sensitivity, and hermetic SMT packaging are mandatory design requirements.

Technical Context

The HMC365G8 implements a static CMOS-compatible divider architecture using InGaP GaAs HBT technology, enabling deterministic divide-by-4 operation without external feedback or loop control. It accepts single-ended or differential RF input (pins 1 and 3), delivers complementary 180°-phase-divided outputs (pins 5 and 7), and requires no AC coupling on VCC (pin 8) but mandates DC blocking on RF inputs.

Its operation down to DC with square-wave excitation distinguishes it from regenerative dividers, while its 80 °C/W thermal resistance and 120 mA supply current at +5 V reflect optimized power efficiency for high-frequency static division. The device maintains specified performance across -40°C to +85°C ambient, with absolute max Vcc = +5.5 V and junction temperature limit of 135°C.

Key Specifications

Pinout & Package

Package: 8-lead glass/metal hermetic surface-mount package with exposed ground paddle; dimensions per outline drawing; Kovar base/cover with 50 µin gold plating over nickel; alumina-loaded borosilicate glass seal.

Key Features

Applications

Equivalent & Alternatives

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

Compared with HMC365G8, HMC492LP5E offers wider bandwidth but fixed divide-by-2 and no differential input, while LMX2594RHBR provides full synthesizer functionality at the cost of higher design complexity and degraded phase noise floor - making HMC365G8 optimal for low-noise, fixed-ratio prescaling where simplicity and stability are prioritized.

Availability

HMC365G8 is available at Aetrix Electronics and suitable for point-to-point radios, VSAT terminals, and fiber optic transceivers requiring stable component supply, hermetic reliability, and verified RF performance across temperature extremes.

Supply support for HMC365G8 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 product lines, emphasizing precision analog, RF, and microwave solutions for defense, aerospace, and communications.

The HMC365G8 belongs to Hittite's legacy SMT GaAs HBT MMIC frequency divider family, engineered specifically for low-phase-noise prescaling in Ku-band PLLs for mission-critical wireless infrastructure.

FAQ

What is the minimum input frequency supported by the HMC365G8?

The HMC365G8 supports DC input for square-wave signals, meaning it can operate with zero-Hz fundamental frequency when driven by a digital clock. For sine-wave inputs, the minimum usable frequency is 0.2 GHz at +25°C, rising to 0.5 GHz under worst-case conditions per datasheet specifications. This makes the HMC365G8 uniquely suited for mixed-signal clock distribution where both digital and RF sources feed the same divider stage.

Does the HMC365G8 require external DC blocking on its RF inputs?

Yes, the HMC365G8 requires DC blocking capacitors on pins 1 and 3 (RF inputs), as stated in the Pin Description section. The device is not internally DC-coupled for RF signal paths - even though it operates down to DC with square-wave excitation, the input port itself must be AC-coupled to prevent bias disruption. Typical designs use 100 pF 0402 capacitors placed immediately adjacent to the package.

Can the HMC365G8 be operated with differential input, and how is it configured?

Yes, the HMC365G8 supports true differential RF input using pins 1 and 3, which are 180° out of phase. To configure differential mode, apply complementary RF signals to both pins with matched trace lengths and impedances. For single-ended use, pin 3 must be AC-grounded via a capacitor to RF ground - the device's functional diagram and pin description explicitly define this dual-mode capability.

What is the thermal resistance (R_TH) of the HMC365G8, and how does it affect thermal design?

The HMC365G8 has a thermal resistance of 80 °C/W from junction to ground paddle. With 120 mA supply current at +5 V, it dissipates ~600 mW - resulting in ~48°C junction-to-paddle rise above PCB ground temperature. Successful thermal design requires soldering the exposed ground paddle directly to a multilayer PCB ground plane with ≥6 thermal vias (0.3 mm diameter) to minimize total thermal resistance and keep junction temperature below 135°C under worst-case ambient.

Is the HMC365G8 pin-compatible with other Hittite divide-by-4 MMICs like the HMC363G8?

No, the HMC365G8 is not pin-compatible with HMC363G8. While both are divide-by-4 GaAs MMICs, the HMC363G8 uses a 6-lead SOT-26 package with different pin assignments (e.g., no dedicated differential input pins), whereas the HMC365G8 uses an 8-lead hermetic package with defined differential I/O and N/C pins. Layout redesign is required for substitution - the HMC365G8's pinout is unique to its performance and packaging requirements.