FEDL7020-02
1
Semiconductor
ML7020
BLOCK DIAGRAM
Input Amplifier 1
SW1
TI–
DTMF
Reception
SP
TI+
TIO
Input Amplifier 2
Input Amplifier 3
CPT
Detection
LI1–
LI1+
LI1O
DETB
RD
SW2
SW4
LI2–
Modem
Reception
LI2O
Output Amplifier 1
CPT
Transmission
TO
1.2 kΩ
Output Amplifier 2
–1
Modem
Transmission
LO–
LO+
XD
1.2 kΩ
Post-
LPF
+1
SW5
DTMF
Transmission
ATT
Output Amplifier 3
SWI
SW3
SGO
SGC
SG
X1
Oscillator
Circuit
X2
CLKO
MCU I/F
* CPT: Call progress tone
* The state shown of each switch is that when the register is set to “0”.
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