9/2004 Seven Band Graphic Equalizer Data Sheet Features The seven band graphic equalizer IC is a CMOS chip that divides the audio spectrum into seven bands, 63Hz, 160Hz, 400Hz, 1kHz, 2.5kHz, 6.25kHz and 16kHz. The seven frequencies are peak detected and multiplexed to the output to provide a DC representation of the amplitude of each band. No external components are needed to select the filter responses. Only an off chip resistor and capacitor are needed to select the on chip clock oscillator frequency. The filter center frequencies track this frequency. Low Power Consumption Only Two External Components On Chip Ground Reference Switched - Capacitor Filters 3.3 or 5 volt Operation 20 dB of Gain Typical On Chip Oscillator Output Multiplexor Variable Decay Time 8 Pin Package Other than coupling and decoupling capacitors, no other external components are needed. The chip supply can be between 2.7 and 5.5 volts with 5 volts providing the best performance. The device has very low quiescent current ( less than 1mA typical) for portable audio devices. The multiplexor is controlled by a reset and a strobe, permitting multiplexor readout with only two pins. The multiplexor readout rate also controls the decay time (10% decay per read), so no external pins are needed for this function. MSGEQ7 Description Applications Portable Stereos Car Stereos Hi-Fi Stereos Spectrum Analyzers Absolute Maximum Ratings Power Supply Voltage Storage Temperature Operating Temperature +6V -60 to + 150 C 0 to 70 C 20 00 63 160 400 1000 2500 6250 16000 Frequency Response Web Site “www.mix-sig.com” © 2004 Mixed Signal Integration 1 Seven Band Graphic Equalizer Data Sheet Electrical Characteristics _________ o ( VDD = +5.0V, T = 25 C) SYMBOL CONDITIONS MIN TYP MAX UNITS 2.7 5.0 5.5 V 0.5 0.8 1.0 mA DC Specifications Operating Voltage VDD Supply Current IDD 1 Mohm Load on Output Output Drive IO 1 mA Output Impedance ZO 700 ohms Output Offset VOS Band Offset Difference Same device 600 mV 200 mV dB MSGEQ7 PARAMETER AC Specifications Gain AV Filter Q Q Output Swing Clock Frequency Input Impedance * includes stray capacitance FCLK ZIN Peak input to DC output, Vin = 100 mVpp, fin = 1 kHz 20 22 24 5.5 6.0 6.5 Vin = 0.3Vpp, fin = 1 kHz 3.5 C = 33 pF*, R = 200 kohms 145 1 4 165 180 V kHz Mohm Ordering Information ___________ Part Number Package MSGEQ7P MSGEQ7N Web Site “www.mix-sig.com” Operating Temperature 8 Pin Dip 8 Pin 150 mils SOIC 0-70 o C o 0-70 C © 2004 Mixed Signal Integration 2 Seven Band Graphic Equalizer Data Sheet Pin Description_________________ 1. VDD 3. 4. 5. 6. OUT STROBE IN GND 7. RESET 8. CKIN Positive Power Supply Typically 5 Volts Negative Power Supply Typically 0 Volts Multiplexed DC Output Channel Selection Pin Audio Input Internally Generated Ground Reference.Typically 2.5V Resets Multiplexor Clock Oscillator Pin VDDA CKIN VSSA RESET OUT GND STROBE 5 MSGEQ7 2. VSS Pin Configuration IN Block Diagram__________________ Audio In CKIN Anti-Alias Filter Clock Oscillator 63Hz Bandpass Peak Detector 160Hz Bandpass Peak Detector 400Hz Bandpass Peak Detector 1kHz Bandpass Peak Detector 2.5kHz Bandpass Peak Detector 6.25kHz Bandpass Peak Detector 16kHz Bandpass Peak Detector Web Site “www.mix-sig.com” Output Multiplexor Reset DC Out Strobe © 2004 Mixed Signal Integration 3 Seven Band Graphic Equalizer Data Sheet Typical Application______________ Multiplexor Operation VDD • 0 0.01 uF L R 0 22K 0 CD 0.1 uF 1 5 3 DC Out MSGEQ7 The DC peak output for measurement is selected using the reset and strobe pins. Reset high resets the multiplexor. Reset low enables the strobe pin. After the first strobe leading edge, 63Hz output is on OUT. Each additional strobe leading edge advances the multiplexor one channel (63Hz, 160Hz, 400Hz, 1kHz, 2.5kHz, 6.25kHz, 16kHz etc.) and this will repeat indefinitely. The multiplexor read rate is also the output decay time control. Each read decays that channel approximately 10%. The strobe timing is shown below: Audio In Strobe 4 Reset 7 2 6 CG 0.1 uF 8 200 k 33 pF VDD tr trs RESET ts tss STROBE to OUTPUT tr - Reset Pulse Width trs - Reset to Strobe Delay ts - Strobe Pulse Width tss - Strobe to Strobe Delay to - Output Settling Time 63 Hz 100 72 18 72 36 160 Hz 400 Hz 1 kHz 2.5 kHz 6.25 kHz 16 kHz 63 Hz 160 Hz nS min uS min uS min uS min uS min (with Cload = 22 pF and Rload = 1 Mohm) Strobe Timing Diagram Web Site “www.mix-sig.com” © 2004 Mixed Signal Integration 4 Mixed Signal Integration Corporation reserves the right to change any product or specification without notice at any time. Mixed Signal Integration products are not designed or authorized for use in life support systems. Mixed Signal Integration assumes no responsibility for errors in this document.