fm34018 Shanghai Fudan Microelectronics Co., Ltd., fm34018 Datasheet - Page 3

• Manufacturer Part Number: fm34018
• Description: Fm34018 Voice Switched Speakerphone Integrated Circuit
• Manufacturer: Shanghai Fudan Microelectronics Co., Ltd.

Product Overview
Instruction
Features
Block Diagram
FM34018 Voice Switched Speakerphone Integrated Circuit
The FM34018 Speakerphone integrated circuit incorporates necessary amplifiers, attenuators, and
control functions to produce a high quality hands-free speakerphone system ,Included are a
microphone amplifier a power audio amplifier for the speaker, transmit and receive attenuators, a
monitoring system for background, sound level, and an attenuation control system which responds
to the relative transmit and receive levels as well as the background level, Also included are all
necessary regulated voltages for both internal and external circuitry, allowing line powered
operation (no additional power supplies required), A Chip Select pin allows the chip to be powered
down when not in use. A volume control function may be implemented with an external
potentiometer. FM34018 applications include speaker phones for household and business use,
intercom systems, automotive telephones, and others.
All necessary level detection and attenuation controls for a hands-free telephone in a
single integrated circuit
Background noise level monitoring with long time constant
Wide operating dynamic range through signal compression
On-chip supply and reference voltage regulation
Typical 100 mW output power (into 25 Ω) with peak limiting to minimize distortion
Chip Select pin for active/standby operation
Linear Volume Control Function
Standard 28-pin plastic DIP package, SDIP package and SOIC package
Ver 2.1
Specification
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