M65854 Mitsubishi, M65854 Datasheet - Page 10

• Manufacturer Part Number: M65854
• Description: DIGITAL ECHO WITH MICROPHONE MIXING CIRCUIT
• Manufacturer: Mitsubishi

(4) Microphone amplifier
as follows.
(3) Clock oscillator circuit
Gv=20log•
Gv(max)=47dB,fcl=225Hz
R1=0 ,C1=0.47µF
Assuming Gv=37dB, fcl=220Hz,for instance,
the constants take the following values.
R1=3.3K ,C1=0.15µF
This IC incorporates a current control type clock oscillator circuit in it, thus providing
circuit configuration just by connecting an Rc for current control pin 1 (MCLKCONT).
Fully internal clock supply prevents occurrence of undesired radiation without affecting
any external circuit.
The oscillator frequency fck is following.
The gain(Gv) and low cut-off frequency(fcl) of microphone amplifier are expressed
Rc
DC Current
R1+1.5K+334K
DIGITAL ECHO WITH MICROPHONE MIXING CIRCUIT
R1+1.5K
1
Clock frequency:fck
oscillator
fcl=
Clock
circuit
2 •(R1+1.5K)•C1
MITSUBISHI
ELECTRIC
1
Note:
The delay time (Td) for echo is determined by the clock
frequency (fck).
fck = 4 MHz(Rc = 22K )
Delay time = 196.6msec
Delay time = 1/fckX48XN
(N = the number of memory bits = 16384
MITSUBISHI SOUND PROCESSOR ICs
MIC
M65854FP
fck = 4 MHz(Rc=22K )
0.22µF
10k
1.5k
2
(
1 0
10k (typ)
REF
4
/
R1
KARAOKE
50
C1
334k
1 4 )
S E R I E S
S E R I E S
5