**HMC539ALP3ETR: A High-Performance GaAs pHEMT MMIC Voltage-Controlled Oscillator from 9 to 5 GHz**

The **HMC539ALP3ETR** represents a significant advancement in RF and microwave signal generation, offering designers a robust and highly integrated solution for a wide range of applications. As a **Monolithic Microwave Integrated Circuit (MMIC)**, this **Voltage-Controlled Oscillator (VCO)** is engineered using a high-reliability **GaAs pHEMT process**, which is the cornerstone of its exceptional performance across its entire frequency band.

A key feature of this VCO is its remarkably **wide tuning range from 5 GHz to 9 GHz**. This broad bandwidth is achieved with a single, positive control voltage, simplifying the design of phase-locked loops (PLLs) and frequency-agile systems. This makes the component incredibly versatile, suitable for use in both commercial and defense-oriented systems such as **point-to-point radios, SATCOM terminals, test equipment, and electronic warfare (EW) systems**.

The **HMC539ALP3ETR** is designed for ease of integration. The chip is housed in a compact, RoHS-compliant **4x4 mm LP3 surface-mount package**, making it ideal for high-density PCB designs. Its architecture incorporates a built-in resonator, negative resistance device, and varactor diode, all on a single die, which minimizes external component count and simplifies board layout. Furthermore, it features a half-frequency output, which is invaluable for simplifying the design of the PLL's feedback path and prescaler in high-frequency applications.

Performance metrics are a highlight of this component. It delivers a consistent **output power of +8 dBm** across the band, ensuring a strong signal for driving mixers or subsequent amplifier stages. It also exhibits excellent **phase noise performance**, typically measuring -118 dBc/Hz at 100 kHz offset from a 6 GHz carrier, which is critical for maintaining signal integrity and minimizing errors in communication systems. The VCO operates from a single +5V supply and includes an integrated supply regulator for improved power supply rejection, enhancing stability in noisy environments.

**ICGOOODFIND:** The HMC539ALP3ETR stands out as a premier MMIC VCO solution, masterfully balancing a wide 5-9 GHz tuning range, high output power, and low phase noise in a miniature, easy-to-use surface-mount package. Its GaAs pHEMT construction ensures high reliability and performance, making it an excellent choice for demanding frequency generation tasks in modern communication and radar systems.

**Keywords:** VCO, MMIC, GaAs pHEMT, Phase Noise, Tuning Range