DOWNLOAD Panasonic KX-NT321RU (serv.man2) Service Manual ↓ Size: 2.29 MB | Pages: 60 in PDF or view online for FREE

9

+

-

+-

+

-

+-

Vref

CC

DET

HD_SP

HD_MIC

HS_MIC+

HS_SP

HS_MIC-

HD_AG

A3.3V

IC20

1

VOUT1

2

VIN1

3

Bypass

4

GND

5

SHUTDOWN

6

VIN2

7

VOUT2

8

VDD

AG

AG

AG

A3.3V

A3.3V

C327

AG

AG

A3.3V

AG

IC24

1

AO

2

A-

3

A+

4

GND

5

B+

6

B-

7

BO

8

VCC

D3.3V

C324

C333

AG

IC23

1

AO

2

A-

3

A+

4

GND

5

B+

6

B-

7

BO

8

VCC

AG

AG

IC21

1

SHUTDOWN

2

BYPASS

3

+IN

4

-IN

5

Vo1

6

VDD

7

GND

8

Vo2

AG

Q14

E

C

B

AG

C331

AG

AG

AG

AG

A3.3V

MUTE_SP1

A3.3V

AG

C346

MIC_SW

C350

A3.3V

AG

AG

A3.3V

C351

AG

AG

AG

A3.3V

C300

L304

L303

SP1

AG

AG

L301

AG

AG

SP2_2

AG

MIC2_2

C302

C301

C339

C355

C325

C356

C309

C340

C311

C358

C353

C338

C354

IC22

1

2

3

45

6

7

8

AG

MIC1+

MIC1-

IC28

9

S2

4

CN

3

C1

5

C0

IC28

11

S0

14

AN

13

A1

12

A0

CN4

1

2

CN5

1

2

C307

C329

C328

L308

L309

MIC3

SP3P

SP3M

C362

C332

C313

L310

C317

C366

C341

C348

C349

C347

C304

C322

C320

HS_MIC+

HS_SP

JK4

HANDSET JACK

1

2

3

4

HD_SP

HS_AG

JK5

HEADSET JACK

1

2

3

4

5

HS_MIC-

HD_MIC

AG

C321

AG

C323

AG

C334

C326

C344

C343

C312

C303

C337

C335

C306

C318

C367

L302

AG

MUTE_SP2

IC29

5

A

1

COM

6

Y2

7

Y1

Q11

E

C

B

Q13

E

C

B

Q12

E

C

B

AG

C316

Q10

E

C

B

C365

L305

L306

CN8

1

2

3

4

5

6

7

8

9

CN7

1

2

3

4

5

6

7

8

9

C342

C345

R332

R302

R300

R312

R339

R318

R319

R331

R316

R346

R337

R341

R351

R320

R329

R321

R350

R325

R326

R307

R336

R304

R348

R328

R338

R314

R343

R309

R327

R344

R330

R349

R342

R335

R340

R313

R303

R306

R333

R352

R310

R345

R317

R334

R315

to SP

to MIC

H:Normal

L:G.722

L:OFF

H:MUTE

L:OFF

H:MUTE

L:OFF

H:MUTE

L:Handset

H:Headset

IC1

HS_OUT

MIC_SW

120

HS_IN

11

2

G722

135

SP_OUT

11

6

MUTE_SP0

107

MUTE_SP1

106

MUTE_SP2

105

MIC_IN

11

3

11

5

HANDSET

-Rx

HEADSET

-Rx

HANDSET

-Tx

HEADSET

-Tx

SP

 PHONE-Rx ( G722 )

SP

 PHONE-Rx

SP

 PHONE-Tx

ANALOG CIRCUIT

10

The key data is under the matrix control by pin21and pin93 to 104 of IC1.
The key information output from KEY_OUT [6-0] is input into KEY_IN [5-0], when the key is pressed.

KEY_OUT is transmitted to KEY_IN as long as button is pressed.
LED will light in 200us seconds after KEY_IN signal.

11

The lighting of the LED is controlled by IC1.
The LEDs light up in a static lighting system.
<controlled by I/O ports of IC1>

• LED1: INTERCOM
• LED2: AUTO ANSWER
• LED3: AUTO DIAL
• LED4: MESSAGE
• LED5: SP-PHONE
• LED12:  CO2
• LED13:  CO1

<controlled by serial I/F of IC13>
LED [6 -11]: CO [3 - 8]

12

This Power Supply Circuit supports the power supply through an Ethernet line called PoE (Power over Ethernet) as well as the
input from a regular AC adapter. It converts the power supply from the both to 5.0V and is supplied to a 3.3V and 1.5V regulator
on the MAIN board.
The power supply circuit consists of the three sections below.

When the hub or router supporting 802.3af is connected to LAN port (JK2), the authentication voltage and the classification volt-
age are supplied between Pin 1, 2 and 3, 6 or Pin 4, 5 and 7, 8 of JK2. 
When this voltage is detected automatically by IC9, it applies the corresponding current and is identified on the hub side, so that
the hub starts to supply 48V.
In the case of both power sources being available, power from LAN port (JK2) and the power from DC jack(JK3) by D3 and D5,
the power from LAN port is supplied to the switching regulator IC8 preferentially.

This switches the power from the DC jack or LAN port by IC8 to generate 5.0V. The switching frequency is 520kHz.

If the voltage supplied to the Switching Regulator Circuit goes under (4.4V), pin1 of IC5 then goes 0V and informs the
decreased voltage for VoIP (IC1).