The CMX994 /CMX994A /CMX994E is a family of direct conversion receiver ICs with PowerTrade™, the ability to dynamically select power vs. performance modes to optimise operating trade-offs.
CMX994 – Standard and low power modes
CMX994A – Standard and additional low power modes
CMX994E – Enhanced, standard and low power modes
The CMX994/A/E offer exceptional blocking performance, typical values are in the range 98dB to 102dB depending on the measurement method. All three devices include a broadband LNA with gain control followed by a high dynamic range, very high IIP2, I/Q demodulator. The receiver baseband section includes amplifiers and precise, configurable bandwidth, baseband filter stages. LO generation is provided by an integer-N PLL and a VCO negative resistance amplifier; an external LO may also be used. LO dividers are provided for flexible multi-band operation.
the CMX994/A/E operates from a single 3.3V supply over a temperature range of –40°C to +85°C and are available in a small 40-pin VQFN (Q4) package.
Q, Are the CMX994A and CMX994E devices pin compatible with the CMX994 in my digital radio? A, Yes all three devices are pin and function compatible. However if the CMX994A or CMX994E are used in an existing CMX994 design, it is recommended that the new extended DC Offset register is utilised. There are additional benefits in adopting the CMX994A and CMX994E including additional low power operating modes and enhanced mixer IM capability, these are illustrated below:
Application Note describing how to estimate the operating frequency of VCO designs using a negative resistance amplifier. An Excel spreadsheet that automates the calculation is available below.
An Excel spreadsheet that calculates the operating frequency of VCO designs using a negative resistance amplifier. An Application Note describing the process is available above.
Through clarification of blocking and second order intermodulation performance, together with empirical measurement, this app note illustrates the excellent characteristics of the CMX994/CMX99A/CMX994E marking its suitability for professional radio designs.
An Application Note demonstrating through the use of a simple RF matching circuit for the CMX994A and CMX994E devices in 400MHz to 470MHz band applications. Comparative measurements are made with the existing EV9942A/E and DE9945A Evaluation Boards throughout and results provided.
An application note that describes the performance characteristics of the CMX994’s LNA and the benefits of this device for typical PMR radio designs.
These scripts are used in the "CMX994 Demonstration" video. The scripts guide the user through Tx/Rx frequency trimming, Rx I/Q DC offset calibration, Rx Equalizer training, Tx I/Q DC offset calibration, and formatted data transfer.
|DE9941||The DE9941 is a small demonstration platform for the CMX994 Direct Conversion Receiver, the CMX998 Cartesian Loop Transmitter and the CMX7164 Multi-mode Wireless Data Modem.||DE9941_Product_Preview|
|EV9942/9942A/9942E||Three versions of the Evaluation Kit are available allowing the user to investigate all aspects of the chosen CMX994, high-performance direct conversion receiver. A common PC-based application identifies the CMX994 version and starts an interactive GUI for configuration and control. A separate hi-res schematic is available for each version of the EV9942.||EV9942_Product_Preview|
Guides to operation and interfacing
EV9942 Board high-resolution schematic. Ver.A04
A common GUI-based application for the EV9942/EV9942A/EV9942E Evaluation Kits. A PE0003 Universal Interface Card is required to use this application. Version 4.1
A simple guide to help users get started evaluating the EV9942, EV9942A and EV9942E Evaluation Kits. Ver.2
EV9942A Board high-resolution schematic. Ver.A02
EV9942E Board high-resolution schematic. Ver.A01
PE0003 USB driver for Windows. Version 1.0
VQFN Design Guidance Notes