M65855FP Datasheet, PDF (7/10 Pages) Mitsubishi Electric Semiconductor – 1 Chip Digital Echo with Microphone mixing Amplifier

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FUNCTION DESCRIPTION
MITSUBISHI SOUND PROCESSOR IC's
50 ^M65855FP
SERIES
KARAOKE
(1) Clock oscillator circuit
The M65855FP incorporates a current control type clock
oscillator circuit in it, thus providing circuit configuration just by
connecting a resistor for current control to pin 16 CLOCK.
Fully internal clock supply prevents occurrence of undesired
radiation without affecting any external circuit
When Rc=120kΩ fck=1MHz
Rc
16
Clock
oscillator
circuit
(2) Delay time Td
The delay time can be calculated by the equation;
Td=N/fs (N=The number of memory bits=20480)
when fck=1MHz,Td can be set at 164ms.
clock frequency
fck
<<Reference>>The M65855FP adopts ADM (adaptive Delta Modulation)
system in A/D,D/A converters.
The sampling frequency can be calculated by the following equation;
fs=clock frequency /8(Hz)
For clock frequency fck=1MHz, the calculated sampling frequency is ;
fs=1MHz/8=125kHz
(3) Mute
1) When power is on
When power is turned on, the mute function works automatically to
prevent noise generation.
(Here,however,"mute" means the function which prevents noise
generation after the reset time.)
Power on Reset
time
period
internal mode ^{Mute time}
Mute off
setting time _{(about 260msec)} time
(a)When power is on ( fck=1MHz)
MITSUBISHI
ELECTRIC
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