三合微科股份有限公司 SM7181 ECHO SAMHOP Microelectronics Corp. DESCRIPTIONS FEATURE SM7181 is an Audio Echo Processor using CMOS Technology. It has buildin AD/DA and 8KBits SRAM for echo effect time delay. * Buildin adjustable OSC. * Buildin power on reset circuit. * Buildin 8KBits SRAM for delay control. * By change oscillator resistor to echo effect time. APPLICATIONS * * * * * VCD Karaok TV Audio System Car Stereo VREF OSC1 OSC2 VDD DGND AGND ADCTL DACTL Page 1 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 OP1-IN OP1-OUT ADC-OUT ADC-IN DAC-IN DAC-OUT OP2-IN OP2-OUT 三合微科股份有限公司 SM7181 ECHO SAMHOP Microelectronics Corp. PIN DESCRIPTION PIN No. PIN NAME I/O FUNCTION 1 VREF AI/O Analog referance voltage 2 OSC1 IN 3 OSC2 OUT 4 VDD Power Power 5 DGND Power Digital negative power supply 6 AGND Power Analog negative power supply 7 ADCTL AIN ADC control 8 DACTL AIN DAC control 9 OP2-OUT AOUT OP2 output 10 OP2-IN AIN OP2 input 11 DAC-OUT AOUT DAC OP output 12 DAC-IN AIN DAC OP input 13 ADC-IN AIN ADC OP input 14 ADC-OUT AOUT ADC OP output 15 OP1-OUT AOUT OP1 output 16 OP1-IN AIN OP1 input AIO: Analog input/output AIN: Analog input AOUT: Analog output Page 2 Oscillator control Resistor 三合微科股份有限公司 SM7181 ECHO SAMHOP Microelectronics Corp. BLOCK DIAGRAM D A C T L OP1-IN Low Pass Filter D A C D A C A D C A D C I N O U T O U T I N AD Converter A D C T L VDD OP2-IN DGND Mix OP1-OUT AGND Low Pass Filter OP2-OUT DA Converter OSC1 OSC Verf Digital Control POR OSC2 VREF Page 3 SRAM 三合微科股份有限公司 SM7181 ECHO SAMHOP Microelectronics Corp. Echo Mode & Surround Mode SM7181 digitize the audio signal through A/D converter and store the value in a First-in- First-out 8Kbits SRAM. After 3.2RCms of delay time the value store in the SRAM will be read out and reconstruct by D/A converter then add with the present sound to become an echo signal output. The echo delay is control by the RC of Pin 2, Pin 3. Audio out Low Pass Filter AD Converter Add Audio In SRAM Low Pass Filter DA Converter Echo Mode ABSOLUTE MAXIMUM RATINGS o ( Ta = 25 C, unless otherwise noted ) Symbol Description Limits Unit Vcc Supply voltage 6.5 V Icc Supply current 100 mA Pd Power dissipation 1.7 W Topr Operation temperature -20 75 Tstg Storage temperature -25 125 Page 4 o o C C 三合微科股份有限公司 SM7181 ECHO SAMHOP Microelectronics Corp. AC CHARACTERISTICS o ( Vcc = 5.0V, f in = 1KHz, Vi = 100mVrms, fck = 4MHz, Ta = 25 C, unless otherwised noted ) SYMBOL PARAMETER Icco Sypply current Gv Voltage gain Vomax Maximum output voltage THD Output disortion 30KHz L.P.F. No Output noise voltage DIN Audio PSRR Power supply rejection ratio Tmute Mute time Test condition Min Typ Max Unit RL = 47K Ω THD = 10% 0.7 60 100 mA -0.5 2.5 dB 1.2 Vrms Echo mode 1.5 3.0 % Surround mode 0.3 1.0 % Echo mode -85 -60 dBV Surround mode -90 -70 dBV -40 -25 dB Vcc = -20dBV f = 100Hz Echo mode 515 520 525 msec Surround mode 122 127 132 msec DC CHARACTERISTICS Symbol Parameter Vcc Supply voltage Icc Supply current V IH "H" input voltage V IL "L" input voltage Limits Min Typ Max 4.5 5 5.5 V 60 100 mA V 3V 1.5V Page 5 Unit V 三合微科股份有限公司 SM7181 ECHO SAMHOP Microelectronics Corp. ECHO MODE APPLICATION CIRCUIT Echo Mode 5V 22 + µ O/P 8.2K 47K 10 µ I/P OP2 3.3 µ 27K 100K 0.01 µ 6800p 27K 5V 47K 8200p 27K 33K 3900p 30K 33K 0.01 µ 560p 22K 12K 3300p 2200p + 22 µ 4.7K 470p OP1 16 15 14 13 12 11 10 19 17 18 SM7181 11 12 13 14 15 18K 220 µ 16 0.1 µ 0.1 µ 10K 200p 100 µ +5V 1 Represent Analog Ground. 2. Represent Digital Ground. Page 6 0.1 µ 10K 50K 三合微科股份有限公司 SM7181 ECHO SAMHOP Microelectronics Corp. MIC PRE-AMP CIRCUIT MIC 1 C 0.02 µF +5V 1µF 1K 20K 560 R 15K 47K 5 6 22 µF + 7 10 µ F 4.7K 47K OUTPUT MIC 2 C 0.02 µF R 15K 100pF 47K 1K 20K 560 1µ F +5V 22 µ F 2 + 100 µF Page 7 1 4 47K 100pF 4.7K 4.7K 3 820pF 820pF 4.7K 10 µ F 三合微科股份有限公司 SM7181 ECHO SAMHOP Microelectronics Corp. SURROUND MODE APPLICATION CIRCUIT OP1 5V 10 µ I/P 47K 0.01 µ 27K 8200p 27K 33K 15 3900p 6800p 30K 33K 0.01 µ 560p 16 27K 14 470p 13 12 11 10 19 17 18 SM7181 11 12 13 14 15 18K 220 µ 16 0.1 µ 0.1 µ 10K 200p 100 µ +5V Page 8 0.1 µ 22K 12K 3300p 2200p 22 + 10K µ 47K O/P