DOWNLOAD Panasonic KX-MC6020RU / KX-FAP317A / KX-FAB318A Service Manual ↓ Size: 32.28 MB | Pages: 127 in PDF or view online for FREE

45

H1

DVDD4

-

+1.5V

Power Supply for DLL

A5

VDD15_1

-

+1.5V

Power SUPPLY

C2

VDD15_2

-

+1.5V

Power SUPPLY

E5

VDD15_3

-

+1.5V

Power SUPPLY

E9

VDD15_4

-

+1.5V

Power SUPPLY

E12

VDD15_5

-

+1.5V

Power SUPPLY

E16

VDD15_6

-

+1.5V

Power SUPPLY

J5

VDD15_7

-

+1.5V

Power SUPPLY

J16

VDD15_8

-

+1.5V

Power SUPPLY

M3

VDD15_9

-

+1.5V

Power SUPPLY

M5

VDD15_10

-

+1.5V

Power SUPPLY

M16

VDD15_11

-

+1.5V

Power SUPPLY

T5

VDD15_12

-

+1.5V

Power SUPPLY

T10

VDD15_13

-

+1.5V

Power SUPPLY

T11

VDD15_14

-

+1.5V

Power SUPPLY

T16

VDD15_15

-

+1.5V

Power SUPPLY

B5

VDD33_1

-

+3.3V

Power SUPPLY

E7

VDD33_2

-

+3.3V

Power SUPPLY

E14

VDD33_3

-

+3.3V

Power SUPPLY

G16

VDD33_4

-

+3.3V

Power SUPPLY

P16

VDD33_5

-

+3.3V

Power SUPPLY

T7

VDD33_6

-

+3.3V

Power SUPPLY

T14

VDD33_7

-

+3.3V

Power SUPPLY

F2

VDDQ_1

-

+2.5V

Power SUPPLY

F4

VDDQ_2

-

+2.5V

Power SUPPLY

G5

VDDQ_3

-

+2.5V

Power SUPPLY

H2

VDDQ_4

-

+2.5V

Power SUPPLY

L5

VDDQ_5

-

+2.5V

Power SUPPLY

P2

VDDQ_6

-

+2.5V

Power SUPPLY

P5

VDDQ_7

-

+2.5V

Power SUPPLY

R4

VDDQ_8

-

+2.5V

Power SUPPLY

B20

GND_1

-

GND

GND

C7

GND_2

-

GND

GND

D8

GND_3

-

GND

GND

D15

GND_4

-

GND

GND

E6

GND_5

-

GND

GND

E8

GND_6

-

GND

GND

E13

GND_7

-

GND

GND

E15

GND_8

-

GND

GND

F5

GND_9

-

GND

GND

F16

GND_10

-

GND

GND

H5

GND_11

-

GND

GND

H16

GND_12

-

GND

GND

J9

GND_13

-

GND

GND

J10

GND_14

-

GND

GND

J11

GND_15

-

GND

GND

J12

GND_16

-

GND

GND

K9

GND_17

-

GND

GND

K10

GND_18

-

GND

GND

K11

GND_19

-

GND

GND

K12

GND_20

-

GND

GND

L2

GND_21

-

GND

GND

L9

GND_22

-

GND

GND

L10

GND_23

-

GND

GND

L11

GND_24

-

GND

GND

L12

GND_25

-

GND

GND

L17

GND_26

-

GND

GND

M9

GND_27

-

GND

GND

M10

GND_28

-

GND

GND

M11

GND_29

-

GND

GND

M12

GND_30

-

GND

GND

N5

GND_31

-

GND

GND

N16

GND_32

-

GND

GND

R5

GND_33

-

GND

GND

R16

GND_34

-

GND

GND

T6

GND_35

-

GND

GND

T8

GND_36

-

GND

GND

PIN NO.

PinName

I/O

Power SUPPLY VOLTAGE

EXPLANATION

46

1. Function

This unit has a lithium battery (B300) which works for the Real Time Clock IC (RTC: inside IC300).
The RTC continues to work, backed up by a lithium battery even when the power switch is OFF.

2. RTC Inside (IC300) Backup Circuit Operation

When the power switch is turned ON, power is supplied to the RTC (inside IC300). At this time, the voltage at pin B22 of the
IC300 is +3.3V. When the power switch is turned OFF, the B300 supplies power to RTC through D300. 
When the power switch is OFF and the voltage of +3.3V decreases, pin B22 of RTC (IC300) becomes roughly the same volt-
age as the battery voltage. RTC goes into the backup mode, in which the power consumption is lower.

The modem (Included IC300) has all the hardware satisfying the CCITT standards mentioned previously.
ALL processing is controlled by the SOC (IC300) according to CCITT procedures.
This modem (Included IC300) has an automatic application equalizer. With training signal 1 or 2 at the time of G3 reception, it can
automatically establish the optimum equalizer.  

The digital image data sent on ATXD line from modem (Included IC300) .
DAA IC100(6

→9,10), Line side DAA IC101 and the NCU section to the telephone line.

The analog image data which is received from the telephone line passes through the NCU section and enters line side DAA*

IC100. The signals are changed to digital data in IC101 (5,6) ,IC100 (9,10

→5) and IC300. In this case, the image signals from

the telephone line are transmitted serially. Here, the internal equalizer circuit reduces the image signals to a long-distance
receiving level. This is designed to correct the characteristics of the frequency band centered around 3 kHz and maintain a con-
stant receiving sensitivity.

The path is the same as Facsimile Reception.

This is the call signal which is generated the SOC (IC300) and sent to the speaker.

 DAA : Direct Access Arrangement

T9

GND_37

-

GND

GND

T12

GND_38

-

GND

GND

T13

GND_39

-

GND

GND

T15

GND_40

-

GND

GND

PIN NO.

PinName

I/O

Power SUPPLY VOLTAGE

EXPLANATION

47

Composed of ITS circuit and NCU circuit.

The analog section works as an interface between the telephone line.
DAA control ITS circuit and NCU circuit. 
DAA control signals are output from Soc IC300.

[NCU]: Network Control Unit the NCU is comprised of the following; DC loop forming circuit to connect with the telephone line;
Switching circuit for other interconnected telephones; Bell detection circuit; Remote fax activation circuit.
Refer to NCU Section (P.48) for the details.

RING

ARXD

ATXD

BTXD

BRXD

IC200

IC100

IC101

EXTRLY

T

R

T

R

SP(+)

SP(-)

HS_MIC(+)

HS_MIC(+)

HS_SP(+)
HS_SP(-)

AGC

16

5

6

5

6

10

9

8

9

15

1

16

14

12

1

3

13

4

5

10

16

KX-MC6020: MAIN BOARD BLOCK DIAGRAM

48

This section is the interface between the telephone line and external telephone. It is composed of an EXT. TEL line relay (RLY100),
bell detection circuit, TAM interface circuit and line amplifier.

1. Circuit Operation

Normally, this relay switches to the external telephone side and switches to the open side while OFF-HOOK.
IC300 (U25) High Level

→Q100 ON→RY100 (ON)

1. Circuit Operation

The signal waveform is indicated below. The bell signal input  to  IC101 and ring detected signal output from pin 16 of IC100.
IC300 monitor this signal and judged as bell.
TEL LINE

→IC101 (8,9 - 5,6)→IC100 (9,10 - 16)→IC300(L23)

1. Function

This unit is compatible with the Caller ID service offered by your local telephone company. To use this feature, you must sub-
scribe to a Caller ID service. The data for the caller ID from the telephone exchange is sent during the interval between the
first and second rings of the bell signal. The data from the telephone exchange is a modem signal which is modulated in an
FSK (Frequency Shift Keying) format. Data “0” is a 1200 Hz sine wave, and data 1 a 2200 Hz sine wave.
There are two types of the message format which can be received: i.e.the single data message format and multiple data mes-
sage format.
The multiple data format allows to transmit the name and data code information in addition to the time and telephone number
data.
When there is multiple data in the unit, the name or telephone number are displayed.

2. Circuit Operation

The caller ID signal input from TEL LINE is processed with Soc (IC300).
TEL LINE

→IC101 (8,9 - 5,6)→IC100 (9,10 - 5)→IC300(AD26)

1. Function

Another telephone connected to same line activates the unit to the FAX mode by using a DTMF signal.

2. Signal Path

TEL LINE

→IC101 (8,9 - 5,6)→IC100 (9,10 - 5)→IC300(AD26)

This circuit is to switch between FAX receiving and the external TAM’s message recording automatically. 
For details, please refer to TAM Interface Section (P.49).