m62457fp Mitsumi Electronics, Corp., m62457fp Datasheet - Page 3

• Manufacturer Part Number: m62457fp
• Description: Peak Hold Ic For 5 Band Spectrum Analayzer Displays
• Manufacturer: Mitsumi Electronics, Corp.

(1) Audio signal passes Amp-a and Amp-d, and it is input into BPF/peak hold
Functional description
Howevwe VCC,GND of analog series had better be common with VCC,GND of
maicroprocessor. THe maicroprocessor does groundisolation to analog series.
Amp-C is the input amplifier to reject common-mode signal (noise),
it utilizes effect of common-mode rejection of Amp-D.
circuit for spectrum analyzer.
(2) BPF/peak hold circuit is setting of 5 band spectrum analyzer
Basic use examples,the last output signal is input into A/D of microprocessor.
(4) Output voltage of peak hold circuit is Vcc/2(Pin.No1)
(3) The hold capasitor of peak hold circuit use inside capasitor.
< center frequency >
Center frequency and Q of BPF is done general setting of like next.
The reset signal is made automatically.
of GND standard and outputs it in PHout (Pin.No.15).
When it is selected by the optput select circuit, it is converted into the voltage
(The value is the design value)
When a selection of hold output is over the reset signal of hold value,
(Discharge pulse : -3dBtyp. output value fall)
f1=105Hz
f2=340Hz
f3=1KHz
f4=3.4KHz
f5=10.5KHz
(The design value is 3.5)
Q=(R1+R2)/R1 ; it is fixed by inside resistor ratio.
w0=gm/C
C:inside capacitor
gm:matual condactance of inside amplifier circuit
(It depends on outside resistor of Pin.No.3)
Peak hold IC for 5 band spectrum analayzer displays
MITSUBISHI SOUND PROCESSOR ICs
M62457FP
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