FO-CC500A
FO-K01A
[3] Circuit description of LIU PWB
(1) LIU block operational description
1) Block diagram
2) Circuit description
The LIU PWB is composed of the following 6 blocks.
1. Speech circuit section
2. Dial transmission section
3. Speaker amplifier section
4. Ringer circuit section
5. CI detection circuit
6. Signal/DTMF transmission level & receiving level
Fig. 5
3) Block description
1. Speech circuit section
•
This circuit is composed by IC101.IC102 and that circumference
circuit.
2. Dial transmission section
•
D.P. transmission: The CML relay is turned on and off for control in
the DP calling system. (Refer to the attached sheet.)
•
DTMF transmission: It is formed in the modem, and is output.
3. Speaker amplifier section
•
Ringer volume
:It is controlled by the combination of the
attenuator value of the LINE DRIVER in the
modem and the ringer sending level sent from
the modem.
•
Speaker volume :It is controlled by the attenuator value of the
IC5 and IC3 (VOL-A,B,C)
4. Ringer circuit section
•
The ringer sound is formed in the tone of modem when CI signal is
detected. The amplifier circuit drives the speaker of the main body.
5 – 10
LIU PWB
HS RECEIVER
TEL MUTE
HS MIC
Q102
CML
LINE
CI
MIC MUTE
IC101
2904
IC101
2904
IC102
2904
IC102
2904
CONTROL PWB
CORDLESS
HANDSET PWB
CORDLESS
PWB
IC12A
IC12B
IC10A
IC10B
IC10C
IC11
IC5
4051
IC7
2113
IC4
TX AMP
SP AMP
IC3:SCE214V
IC12D
DTMF MUTE
RCVOL
1
0
1
RLYCONT
SIG MUTE
SP MUTE
SPEAKER
VOLA
CML
TONE
CML
CI
DTMF MUTE
RCVOL
TEL MUTE
MIC ENABLE
MIC GAIN
GAIN
LPF
ADC
DAC
LINE IN ENABLE
LININ GAIN
0,20,25,30dB
0dB
0,–4dB
0,6dB
ADC GAIN
DAC GAIN
RX AMP(MIC AMP)
SIGRX
TELOUT
SIGTX
SPKRP
MUTE,0,–6,–12dB
LINE OUT ATTENUATION
SP
DRIVER
LINE
DRIVER
LINEOUT
LNINSEL
RT LOOP
MICP
LINEIN
SPEAKER
OUT ENABLE
LINE OUT
ENABLE
W-TONE
SIG MUTE
SP MUTE
MIC MUTE
SASTXD,SASRXD
RLYCONT
VOLA
VOLB
VOLC
CI
VOLB
VOLC
W-TONE
0
DSSIN
0
1
0,0
1,0
1,1
1,1
0,0
0,1
1,0
DSSIN
DSSIN
MICIN
LINEIN GN
DAC GN
DAC
F
F
SPKOP
LINE
LINE ATTN
SPKROUT GN
TXCTRL
RF AUDIOIN 1 GN
RF AUDIOIN 1 GN
VOLUME 1
TG1,
TG2
GPIO
TG1,
TG2
VOLUME 1
ADC GN
ADC GN
AUDIOIN 1 GN
AUDIOIN 1 GN
PRE
SCALER
PRESCALE
SETTING
POSTSCALE
SETTING
POST
SCALER
TXCTRL
SIDE TONE 1 GN
SIDE TONE 1 GN
ADC
ADC
MIC IN
MIC GN
LINEIN GN
SPKR OUT GN
SPKOP
LINE O
DAC
DAC GN
LINE ATTEN
AUX VOLUME
TG3
AUXDAC
SP MUTE
SP MUTE
SPEAKER
EMJSP MUTE
EMJSP MUTE
EMJSP
EMJMIC
RECEIVER
MIC
EMJSP AMP
ECHOATTN
C
INCOM
DSSOUT
IC1:20438
IC2:MERLIN
IC5:MERLIN
IC8:20438
F
F
IC5:MERLIN
IC6
IC7
Summary of Contents for FO-CC500
Page 82: ...FO CC500A FO K01A Control PWB parts layout Top side 6 7 ...
Page 83: ...FO CC500A FO K01A Control PWB parts layout Bottom side 6 8 ...
Page 87: ...FO CC500A FO K01A LIU PWB parts layout Top side 6 12 ...
Page 88: ...FO CC500A FO K01A LIU PWB parts layout Bottom side 6 13 ...
Page 92: ...FO CC500A FO K01A 6 17 Cordless PWB parts layout Top side ...
Page 93: ...FO CC500A FO K01A 6 18 Cordless PWB parts layout Bottom side ...