TDA7541B AM/FM car radio tuner IC with stereo decoder and intelligent selectivity system Features FM part AGC generation by RF and IF detection st I/Q mixer for 1 IF 10.7 MHz with image rejection nd Mixer for 2 IF 450 kHz LQFP64 Internal 450 kHz band pass filter with bandwidth control by ISS High performance fast PLL for RDS- Fully integrated FM demodulator with noise System cancellation IF counter for FM and AM with search stop AM part signal Wide and narrow AGC generation Quality detector for level, deviation, st Mixer for 1 IF 10.7 MHz, AM up adjacent channel and multipath conversion ISS (Intelligent selectivity system) for nd Mixer for 2 IF 450 kHz cancellation of adjacent channel and noise influences Integrated AM-demodulator Adjacent channel mute AM IF noise blanking Fully electronic alignment Stereo decoder Independent weather band input PLL with adjustment free, fully integrated 2 All functions I C bus controlled VCO Automatic pilot dependent MONO/STEREO switching Description Programmable ROLL-OFF compensation The TDA7541B is a high performance tuner High cut and stereo blend-characteristics circuit with stereo decoder for AM/FM car radio. It programmable contains a mixer, IF amplifier, demodulator for AM Dedicated RDS mute and FM, stereo decoder, quality detection, ISS Audio noise blanker filter and PLL synthesizer with IF counter on a single chip. Use of BICMOS technology allows the Additional features implementation of several tuning functions and a VCO for world tuning range minimum of external components. Table 1. Device summary Order code Package Packing TDA7541B LQFP64 (10 x 10 x 1.4 mm) Tray TDA7541BTR LQFP64 (10 x 10 x 1.4 mm) Tape and reel TDA7541BW LQFP64 (14 x 14 x 1.4 mm) Tray TDA7541BWTR LQFP64 (14 x 14 x 1.4 mm) Tape and reel September 2013 Doc ID 16048 Rev 2 1/77 www.st.com 1Contents TDA7541B Contents 1 Block circuit diagram 6 2 Pin connection and pin description 7 2.1 Pin connection 7 2.2 Pin description 8 3 Electrical specifications and characteristics 10 3.1 Thermal data 10 3.2 Absolute maximum ratings 10 3.3 Electrical characteristics 10 3.3.1 Globals 10 3.3.2 FM section . 11 3.3.3 AM section . 17 3.3.4 Stereo decoder section . 19 3.3.5 PLL section 24 4 Functional description 26 4.1 FM part . 26 4.1.1 Mixer 1 AGC and IF amplifier . 26 4.1.2 Mixer2, limiter, FM demodulator and spike cancellation 26 4.1.3 Quality detection and ISS . 26 4.1.4 Block diagram quality detection principle 29 4.1.5 Strong adjacent channel correction 30 4.1.6 Weak signal mute . 30 4.1.7 Weather band input 31 4.2 AM section 31 4.2.1 Usage of control bit ADSEL (Addr23D7) 32 4.3 Stereo decoder . 32 4.3.1 Decoder . 32 4.3.2 Noise blanker . 34 4.3.3 Functional description of the multipath detector 37 4.3.4 Quality detector . 37 4.3.5 AFS control and stereo decoder mute 37 4.4 PLL and IF counter section . 38 2/77 Doc ID 16048 Rev 2