Ten-segment spectrum display

This is a schematic diagram of a ten-segment spectrum display . LM324 forms a ten-segment bandpass filter , and five
TA7666P9 form a ten-segment display driver circuit. The ten segments adopt a 2-octave relationship, and their center frequencies are:
3ZHz, 63№, 1 25№, 250Hz, 500Hz, 1 Yao, 2№, 4kHz, 8‰, and 16kHz. The display dynamic range
is 16dB, the reference level is set to OdBo display driver TA7666P, each LED level is OdB5 out, 10dB,
13dB, 16dBo. LM324×3 constitutes the band-pass filter of each section. LM324 contains four operational amplifiers, a total of Twelve operational amplifiers,
ten of which are used as band-pass filters, and the remaining two are used as voltage followers for isolation.
    First calculate and select the suppression ratio A and the Q value of the bandpass filter. The selection of suppression ratio should be greater than
16dB of the display dynamic range, take 20dB. Then calculate the Q value of the bandpass filter according to the Q value calculation formula . Since the frequency points are in a 2-
fold relationship, substitute =2 foA=20 to obtain Q-6,63, and take Q=lo.