**HMC659: A Comprehensive Overview of the 20 GHz GaAs pHEMT MMIC Low Noise Amplifier**

The **HMC659** is a high-performance **Gallium Arsenide (GaAs) pseudomorphic High Electron Mobility Transistor (pHEMT)** Monolithic Microwave Integrated Circuit (MMIC) low noise amplifier designed for a broad range of applications operating up to **20 GHz**. Representing a significant achievement in RF and microwave design, this component is engineered to provide exceptional gain and minimal noise figure, making it a critical building block in systems where signal integrity is paramount.

A key attribute of the HMC659 is its outstanding **low noise figure of 1.8 dB**, which is maintained across a wide frequency band. This exceptional performance ensures that the amplifier introduces minimal additional noise, thereby preserving the quality of very weak incoming signals. This is particularly crucial in sensitive receiver chains for applications such as **radio astronomy, satellite communications, and radar systems**.

Complementing its low noise performance is its high linearity and impressive **gain of 18 dB**. This high gain allows the HMC659 to effectively boost signal strength early in the signal chain, dominating the noise contribution of subsequent components in the system. The amplifier operates from a single positive supply, typically between +3V to +5V, and incorporates self-biasing, which simplifies the overall system design and reduces the part count on the printed circuit board (PCB).

Fabricated using a advanced GaAs pHEMT process, the MMIC technology ensures high integration, reliability, and repeatable performance. The device is housed in a **RoHS-compliant, surface-mount 2x2 mm ceramic package**, making it suitable for high-volume automated assembly processes. Its small form factor is ideal for space-constrained applications without compromising on thermal or electrical performance. The HMC659 is also internally matched to 50 Ohms, which simplifies integration and reduces design time by minimizing the need for external matching components.

Typical applications that benefit from the HMC659's capabilities include:

* **Point-to-point and point-to-multi-point radios**

* **Military and commercial radar systems**

* **Satellite communication (SATCOM) terminals**

* **Electronic Warfare (EW) and Electronic Countermeasures (ECM) systems**

* **Test and measurement equipment**

**ICGOOODFIND:** The HMC659 stands out as a superior solution for high-frequency, low-noise amplification needs. Its combination of an ultra-low noise figure, high gain, and robust integration within a miniature package makes it an excellent choice for designers aiming to maximize receiver sensitivity and performance in demanding microwave applications.

**Keywords:** Low Noise Amplifier, GaAs pHEMT, 20 GHz, MMIC, High Gain