FX009 Amplifier Array

• 8 Digitally Controlled Amplifiers
• 15 Gain/Attenuation Steps
• 7 Trimmers, with a ±3dB Range in 0.43dB Steps
• 1 'Volume' Trimmer, with a ±14dB Range in 2.0dB Steps

• 8-Bit Serial Data Control
• Output Mute/Powersave Function
• Audio and Data Gain Control Applications
• Cellular, PMR, PABX Applications

The FX009A Digitally Adjustable Amplifier Array is intended to replace trimmer potentiometers and volume controls in Cellular, PMR, Telephony and Communications applications where DC, voice or data signals need adjustment. The FX009A is a low-noise single-chip LSI consisting eight digitally controlled amplifier stages, each with 15 distinct gain/attenuation steps. Control of each amplifier is an 8-bit serial data stream. Seven of the amplifier stages offer a ±3dB range in steps of 0.43dB, while the remaining one offers a ±14dB range in steps of 2dB and is intended for volume control applications. Each amplifier includes a 16th 'Mute' state which sets the output to bias (VDD/2) and power saves the entire section. A minimum current drain may be achieved by muting all eight sections. This product replaces the need for manual trimming of audible signals by using the host microprocessor to control the set-up of all audio levels digitally.
Applications include:

• Control, adjustment and set-up of communications equipment by an Intelligent ATE without manual intervention – e.g. Deviation, Microphone and L/S Level, Rx Audio Level, etc.
• Automatic Dynamic Compensation of drift caused by variations in temperature, linearity, etc.
• Fully automated servicing and re-alignment.