Analog Devices Inc. 110227-HMC734LP5

Overview

HMC734LP5 from Analog Devices (formerly Hittite Microwave) is a GaAs InGaP HBT MMIC voltage-controlled oscillator with integrated divide-by-4 prescaler, operating at 8.6–10.2 GHz RF output and 2.15–2.55 GHz divided output, delivering +18 dBm RF power from +5 V supply, with −100 dBc/Hz phase noise at 100 kHz offset, used in SATCOM transceivers and point-to-point radio local oscillators.

For engineers reviewing the HMC734LP5 datasheet, HMC734LP5 pinout, HMC734LP5 application, or HMC734LP5 equivalent, this page delivers verified electrical specs, package mapping, functional pin roles, real-world use cases, and validated alternative VCOs for microwave frequency synthesis in ruggedized RF systems.

Technical Context

The HMC734LP5 integrates monolithic resonator, negative resistance device, and varactor diode - eliminating external tuning components. Its divide-by-4 prescaler operates independently and can be disabled via open-circuiting Vcc(Dig), reducing total current draw by ~100 mA.

Phase noise stability across −40°C to +85°C is enabled by the monolithic GaAs HBT structure, while pulling (38 MHz pp into 2.0:1 VSWR) and pushing (30 MHz/V) are specified under +5 V bias, supporting robust LO generation in wide-temperature military and industrial radios.

Key Specifications

Pinout & Package

Package: 32-lead leadless QFN, 5×5 mm body, exposed ground paddle, Sn/Pb finish, MSL3 rating. Requires soldering of all ground leads and paddle to PCB RF ground per Hittite land pattern guidelines.

Key Features

Applications

Equivalent & Alternatives

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

Compared with HMC734LP5, HMC733LP4 offers smaller size and lower cost but sacrifices /4 output and upper-frequency reach; ADF4351 provides programmability and integration but cannot match the HMC734LP5's −100 dBc/Hz phase noise or monolithic Ku-band stability.

Availability

HMC734LP5 is available at Aetrix Electronics and suitable for point-to-point radio, SATCOM terminals, and military tactical radios requiring stable component supply, consistent RF performance across temperature, and long-term obsolescence management.

Supply support for HMC734LP5 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, including MMIC VCOs, LNAs, and switches for defense, aerospace, and communications markets.

The HMC734LP5 belongs to Hittite's legacy MMIC VCO family, engineered specifically for Ku-band wireless infrastructure and electronic warfare systems demanding low phase noise, high output power, and monolithic reliability.

FAQ

What is the operating temperature range for the HMC734LP5?

The HMC734LP5 is rated for continuous operation from −40°C to +85°C ambient temperature. Its monolithic GaAs HBT structure ensures stable phase noise and frequency drift (1.1 MHz/°C) across this full industrial/military range, with characterization data provided at −40°C, +25°C, and +85°C in the official datasheet revision v03.0609. Thermal resistance is 39.5°C/W junction-to-paddle.

Can the HMC734LP5's divide-by-4 function be disabled, and how does it affect current draw?

Yes, the HMC734LP5's divide-by-4 prescaler can be disabled by leaving pin 6 (Vcc(Dig)) unconnected - this reduces total supply current from 218 mA typical to ~118 mA. The RFOUT path remains fully operational, preserving the 8.6–10.2 GHz output and +18 dBm power. This feature is documented in the "General Description" and "Electrical Specifications" sections of the HMC734LP5 datasheet.

What is the recommended PCB grounding practice for the HMC734LP5?

The HMC734LP5 requires all ground pins (pins 5, 11, 18) and the exposed bottom paddle to be soldered to a solid RF/DC ground plane using ≥6 thermal vias. Per Hittite Application Note AN-1001, insufficient grounding causes degraded phase noise and output power instability. The evaluation board (110225) uses Rogers 4350 substrate and specifies minimum 0.3 mm via diameter and 0.8 mm center-to-center spacing.

Does the HMC734LP5 require external matching components for RFOUT or RFOUT/4?

No, the HMC734LP5 requires no external matching components for either RFOUT or RFOUT/4. Its monolithic design integrates all resonant and tuning elements. However, AC coupling capacitors are mandatory: a DC-blocking capacitor must be placed in series with RFOUT (pin 19) and RFOUT/4 (pin 4), as both outputs are AC-coupled per the Pin Descriptions table in the datasheet.

What is the absolute maximum tuning voltage for the HMC734LP5's VTUNE pin?

The absolute maximum tuning voltage for the HMC734LP5's VTUNE pin (pin 29) is +15 Vdc, as specified in the Absolute Maximum Ratings table. Operation beyond this voltage risks permanent damage to the integrated varactor diode. The functional tuning range is 1–13 V, delivering full 8.6–10.2 GHz coverage; applying 15 V is permissible only as a non-operational limit, not a recommended bias condition.