The MX128 is a full-duplex frequency inversion scrambler designed to provide secure conversations for 46/49 MHz cordless telephone users. The RX and TX audio paths consist of the following:
1. A switched-capacitor balanced modulator with high baseband and carrier rejection.
2. A 3.3 kHz inversion carrier (injection tone).
3. A 3100 Hz lowpass filter.
4. Input op-amps with externally adjustable gain.

The MX128 uses mixed signal CMOS switched-capacitor filter technology and operates from a single supply in the range of 3.0V to 5.5V. The inversion carriers frequency and filter switching clock are generated on-chip using an external 10.24 MHz or 3.58/3.6864 MHz crystal or clock input (selectable).
The MX128 is available in the following package styles: 16-pin SOIC (MX128DW) and 16-pin PDIP (MX128P).

FEATUREs
● Full-Duplex Audio Processing
● On-Chip Filters
● Carrier Rejection >55dB
● Uses IF (10.24 MHz) Clock
● Requires No Extra Crystal
● Excellent Audio Quality
● Low Voltage 3.3V/5.0V Operation
● ECPA* Qualified Voice Protection

APPLICATIONs
● Battery Powered Portability
● Cordless Telephones
● Wireless PBXs