RF Direct Conversion Receiver ICs
Direct Conversion Receiver Family with PowerTrade™ Flexible Power vs. Performance Modes
- CMX994 - Standard and Low Power Modes
- CMX994A - Standard and Additional Low Power Modes
- CMX994E - Enhanced, Standard and Low Power Modes
Rx Single Conversion to Zero IF, Near-zero IF or Low IF; Zero IF Eliminates Image Responses
Very High Mixer IIP2 for Practical Zero IF Receiver
100MHz to 1000MHz I/Q Demodulator (CMX994A/E)
100MHz to 940MHz I/Q Demodulator (CMX994)
Extended Operation down to 50MHz
LNA with Gain Control
Precise Filtering with 1:2:4 Bandwidth Select Control
Mixer Bandwidth up to 20MHz
- LO synthesiser
- VCO Negative Resistance Amplifier
- Rx LO Divide by 2, 4 or 6 Modes
- Tx LO Output with Divide by 1, 2, 4 or 6 Modes
Small Size 40-pin VQFN Package
Analogue/digital Multi-mode Radio
Software Defined Radio (SDR)
Data Telemetry Modems
Constant Envelope and Linear Modulation
Rx Function Compatible with CMX998
Cartesian Feedback Loop Transmitter
Narrowband e.g.: 25kHz, 12.5kHz and 6.25kHz
Wideband Data e.g. >1MHz Bandwidth
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.
Direct conversion receiver family with PowerTrade™ flexible power vs. performance modes
CMX994 - Standard and low power modes
CMX994A - Standard and additional low power modes
CMX994E - Enhanced, standard and low power modes
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 devices operate 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.
The CMX994A enables a significant reduction in power by allowing LO phase correction to be turned off. A further reduction is made possible by the facility to disable either the I or Q channel. The CMX994E expands on that by adding an enhanced performance mode that features improved intermodulation in the receive path mixers.
Operate 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.
Design Support Information
|Frequency Estimation for a VCO using a Negative Resistance Amplifier
||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.
|Excel Spreadsheet - Frequency Estimation for a VCO using a Negative Resistance Amplifier
||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.