ST的TDA7540B是集成了立体声译码器和智能安全系统(ISS)的AM/FM 汽车收音机调谐器.这中高性能的集成电路包括混频器,IF放大器,AM和FM解调器,立体声译码器,品质检测,ISS滤波器,以及带IF计数器的PLL合成器.本方案给出了TDA7540B的主要性能.

TDA7540B AM/FM Car Radio Tuner IC with STEREO DECODER and Intelligent Selectivity SYSTEM (ISS)

The TDA7540 is a high performance tuner circuitfor AM/FM car radio.

It contains mixer, IF

amplifier, DEMODULATOR for AM and FM, stereodecoder, quality detection, ISS FILTER and

PLL SYNTHESIZER with IF counter on a SINGLE chip.Use of BICMOS TECHNOLOGY allows the implementation of several tuning functions and a MINIMUM of external components.

主要特性:

FM部分:

■ RF AGC generation by RF and IF detection

■ I/Q mixer for 1st FM IF 10.7MHZ with image rejection

■ Mixer for 2nd IF 450KHZ

■ Internal 450KHz bandpass filter with bandwidth CONTROL by ISS

■ Fully INTEGRATED FM-demodulator with spike cancellation

AM部分:

■ Wide and narrow AGC generation

■ Mixer for 1st IF 10.7MHz, AM upconversion

■ Mixer for 2nd IF 450kHz, AM downconversion

■ Integrated AM-demodulator

■ AM IF- and audio noise blanking

立体声译码器:

■ PLL with adjustment free, fully integrated VCO

■ Automatic pilot dependent MONO/STEREO SWITCHING

■ Programmable ROLL-OFF compensation

■ High cut and stereo blend-characteristics programmable

■ Dedicated RDS-mute

■ Internal noise blanker with several threshold controls

其它特性:

■ VCO for world tuning range

■ High performance fast PLL for RDS-System

■ IF counter for FM and AM with search stop signal

■ Quality detector for level, deviation, adjacent channel and multipath

■ ISS (Intelligent Selectivity System) for cancellation of adjacent channel and noise influences

■ Adjacent channel mute

■ Fully electronic alignment

■ All functions I2C-Bus controlled