Communications
CMX994 - Direct Conversion I/Q Demodulator - DCRx has the Edge
CML Microcircuits a leading innovator and provider of low-power semiconductors for global wireless and two-way radio communications markets, has added a new Direct Conversion Receiver IC (DCRx) to its family of RF Integrated Circuits.
The Until recently, most radios have used the superheterodyne (Superhet) receiver, however enhancements in semiconductor technology have enabled the integration of DCRx, allowing it to become the technology of choice for radio receivers in many applications. A DCRx mixes the wanted RF signal down to 0Hz in a single quadrature mixing process using a local oscillator (LO) tuned to the wanted RF channel frequency. Selectivity filtering and gain can now take place at baseband with practical, low power, analogue and digital circuits. DCRx also eliminates the need for an image-reject filter.
Key features of the CMX994 include on-chip VCO for VHF applications, an operating range of 100MHz to 1GHz, precision baseband filtering with selectable bandwidths and the smallest PCB area, typically less than 50% of a dual superhet. Another important feature is the single ended RF connections meaning no baluns are required.
The small size and flexibility of Direct Conversion make it a key element for the next generation of multi-mode software defined radios (SDR) for wireless data and digital two-way radio applications.
The CMX994 operates at 3.0 – 3.6 V, and comes in a Q4 40 VQFN package.