You would need to use an analog switch to demux the output into seven outputs. If you want to run standalone (no micro), things become complicated. Then connect a 50K pot from negative input to +5V, adjust pot for 0 volts out with no audio input to the MSGE7. Place a 1K resistor from opamp output to negative input. You would connect the output of the MSGE7 to the positive input of the op amp. But be aware that the output is refenced at around 500mv, so for best results use an rail to rail opamp to ground reference the output. I've been playing with these and yes you should be able to drive the LM3914 series of chips OK. The multiplexer readout rate also controls the decay time (10% decay per read), so no external pins are needed for this function. the multiplexer is controlled by a reset and a strobe, permitting multiplexer readout with only two pins. The device has very low quiescent current (less than 1ma typical) for portable audio devices. The chip supply can be between 2.7 and 5.5 volts with 5 volts providing the best performance. Other than coupling and decoupling capacitors, no other external components are needed. The filter center frequencies track this frequency. Only an off chip resistor and capacitor are needed to select the on chip clock oscillator frequency. No external components are needed to select the filter responses. The seven frequencies are peak detected and multiplexed to the output to provide a DC representation of the amplitude of each band. The seven band graphic equalizer IC is a CMOS chip that divides the audio spectrum into seven bands.
0 Comments
Leave a Reply. |