In a congested wireless environment, an increasing number of applications require the capability to measure frequency spectrum. This motivates the development of a spectrum-sensing module comprised of a minimal architecture spectrum analyzer with integrated frequency synthesized tuning. The module features a frequency synthesizer with digital frequency controlled inputs and an integrated analog-to-digital converter to digitize the output. This module can be incorporated as a basic component in more complex system that require spectral sensing such as spectrum monitoring systems and dynamic spectrum access systems. The proposed single-chip spectrum-sensing module with digital output was fabricated in a standard 0.5 micron CMOS process. Measured results of a prototype are presented for operating range of 20 to 180 MHz.