GaAs PAs for Battery-Powered Devices

CML Micro has expanded its SµRF product lineup with the introduction of a pair of high-efficiency single- and two-stage power amplifiers (PAs) designed to cater to the needs of dual-cell lithium battery-powered wireless devices. These amplifiers are engineered to deliver exceptional performance across a wide range of applications, making them a versatile choice for developers in the portable communications sector.

The newly introduced PAs are capable of operating within a supply voltage range of 6.0-V to 9.5-V, allowing them to be directly powered by a dual-cell lithium battery without the necessity of a voltage regulator. Additionally, both amplifiers come equipped with an integrated active bias circuit that offers temperature compensation, streamlining the design process for developers working on portable communication products.

One of the amplifiers, the CMX90A007, is a high-gain, two-stage Gallium Arsenide-based Heterojunction Bipolar Transistor (InGaP/GaAs HBT) amplifier that can function as a stand-alone final-stage power amplifier or as a driver stage for the CMX90A009. The CMX90A009 is a thermally optimized, single-stage GaAs HBT power amplifier designed to serve as the output stage in a high-power amplifier transmit chain. Both devices support a broad frequency range of 136-1000 MHz, making them suitable for various frequency bands and applications, including two-way radios.

At 435 MHz and 7.4 V, the CMX90A007 delivers an impressive +33.5 dBm (2.2 W) output power with over 55% efficiency, while the CMX90A009 offers a +40.0 dBm (10 W) output power with greater than 60% efficiency at the same frequency and voltage. These performance metrics make the PAs ideal for applications requiring high power output and efficiency.

Furthermore, the QFN and DFN-packaged PAs are designed for long-term reliability and optimized for integration onto space-constrained PCBs. The off-chip matching capability allows electronic designers to fine-tune the power amplifiers for optimal performance in various applications utilizing dual-cell lithium battery technology, such as critical communications handsets, private and land-mobile hand-portables, two-way radios (both analogue and digital), and wireless data modem networks.

Rob Smith, the Product Line Director at CML Micro, highlighted the significance of the new power amplifiers in addressing market demands. He emphasized the challenges faced by organizations, particularly two-way radio manufacturers, due to supply chain issues related to obsolescence in high-performance power amplifiers operating around 7.5 V. The introduction of these GaAs technology-based single- and two-stage power amplifiers aims to provide a sustainable solution and long-term support to the market, ensuring continuity for various applications. The CMX90A007 and CMX90A009, along with evaluation boards, are currently available in Asia, Europe, and the US, catering to the global demand for high-performance power amplifiers.