Low-noise common-gate amplifier for wireless communications

摘要

With emergence of Bluetooth™ and other wireless standards, it has become increasingly desirable and practical to use low-cost wireless links, instead of cables, between devices, such as computers, printers, and personal digital assistants. Vital to these wireless links are the amplifiers that receive transmitted signals. One amplifier form, known as a common-gate amplifier, generally includes bias circuitry that requires large areas of an integrated-circuit chip or increases power usage and adds noise. Accordingly, the inventor devised an exemplary common-gate amplifier that includes an inductor coupled between the gate and drain of an amplifying transistor. The inductor acts as a short circuit at low frequencies, forcing the transistor to function at these frequencies as a diode and thus reduces the need for further bias circuitry. Other inventive embodiments include wireless receivers, transceivers, programmable integrated circuits, and electronic devices that incorporate the exemplary amplifier.