DESCRIPTION

· The CMX264 is a frequency domain scrambler designed for analogue cellular phone systems.
· It features separate Tx and Rx paths for full duplex operation and is controlled via a simple serial interface.
· Scrambling is achieved by splitting the audio band into two sub-bands and frequency inverting each.
· The split-point can be fixed or rolling among four settings, ensuring transmitted audio is unintelligible to eavesdroppers.
· Descrambling requires the receive device to be set to the same split point as the transmitter.
· Synchronous cycling of Tx and Rx devices through the same sequence of split points results in clear audio recovery.
· A 4.433619MHz crystal allows programming of up to four split points.
· The device is compatible with existing cellphone circuitry.

FEATURES

· Ensures privacy in communications.
· Supports fixed or rolling code scrambling.
· Full duplex operation capability.
· Includes a standby mode for power saving.
· Delivers high quality recovered audio.
· Utilizes split band inversion for scrambling.
· Compact, low height, surface mount package.
· Operates at low current and low voltage.
· Designed for 3.0V low power operation.
· Operates at 4.433619MHz.

APPLICATIONS

· Analogue cellular phone systems requiring secure communication.
· Devices needing full duplex audio scrambling and descrambling.
· Systems where privacy and audio quality are critical.
· Low power, low voltage electronic devices.
· Compact, surface mount technology applications.