DOWNLOAD Panasonic KX-UT113RU / KX-UT113RU-B / KX-UT123RU / KX-UT123RU-B (serv.man3) Service Manual ↓ Size: 2.49 MB | Pages: 93 in PDF or view online for FREE

7

LCD data are output from pin M3 of IC501 to LCD module.
LCD contrast is set by electronic volume in LCD module.
+3.3V of the power supply voltage is pressurized about four/three times in the LCD module and used as LCD driving voltage
(approx. 10.0V).
The driving voltage is observed between Pin 12 (V0) and Pin 13(XV0) of CN504.

The lighting of the backlight is controlled by Q503(KX-UT123 only).
The PWM (Pulse Width Modulation) signal is output from IC501-B8 pin and the brightness is changed according to its duty ratio.

Reset Signal is output from IC505 and input into IC501-pin L3.

8

The PHY IC (IC401) is used for the Ethernet interface.
It is connected from IC401 to the Ethernet port (JK401) through a transformer and so is  isolated.
Also, LAN port (JK402) gets power from the Ethernet line for PoE (Power over Ethernet) as shown below.
It is connected between IC401 and the BBIC (IC501) by high-speed bus called MII (Media Independent Interface) bus operating
with 25MHz.
Note:

UT113 does not have a PC port.

9

1. Speaker phone call

Transmitting signal is input from microphone and amplified by IC103 

→ input to IC501-pin G2 → A/D conversion, Gain adjust-

ment and echo cancel by a built-in DSP of IC501.
Receiving signal input from IP Line 

→ Gain adjustment and D/A conversion by DSP of IC501 → output from IC501-pin E1,F1

→ Amplified by IC101 and output to Speaker.
Class D Amp IC101 is controlled as follows;
IC101-pin1 H (3.3V): Amp ON , IC101-pin1 L (0V): Amp OFF

2. Handset call 

Transmitting signal is input from handset microphone and amplified by IC103 

→ input to IC501-pin J1 → A/D conversion, Gain

adjustment by a built-in DSP of IC501.
Receiving signal input from IP Line 

→ Gain adjustment and D/A conversion by DSP of IC501 → output from IC501-pin H1,G1

→ output to handset speaker.

+

-

MIP

AG3

OPBIAS

SPP

SPN

SPAMPEN

C117

5V

AG3

MICBIAS

C134

R101
R102

R130

R131

SPP

SPN

MIP

MIN

L101

L102

IC103

3

2

1

C122

C110

R124

R125

C129

C130

R126

R127

C111

C101
C102

C135

AG3

L103

L104

D108

DL101

1

2

3

C174

C175

C121

C118

C176

C177

C123

C126

C138

DG

DG

DG

DG

DG

DG

DG

DG

DG

DG

C182

C183

C184

R109

R152

C185

AG3

C105

IC101

1 STBY

2 NC

3 IN+

4 IN-

5

OUT+

6

VDD

7

GND

8

OUT-

9

FIN

CL103

CL104

CL106

CL105

DG

DG

C191

C190

C192

C193

AG3

AG3

R118

R119

D107

D101

D102

IC501

BBIC

E3

F1

E1

G2

+

-

AG3

HSMICINP

C115

OPBIAS

MICBIAS

AG

AG3

AG

AG

JK101

1
2
3
4

5

R132

R133

IC103

5

6

7

C127

C128

R122

R123

C109

C124

R128

R129

D103

D104

D105

C125

C137

C139

C179

C180

C181

DG

DG

DG

DG

R112

R153

C186

AG3

C107

DG

DG

C143

C141

L108

L107

DG

DG

C189

C188

C146

C147

R120

R121

D106

L106

L105

IC501

BBIC

C542

DG

J1

H1

G1

10

3. Headset Call

Transmitting signal is input from headset microphone and amplified by IC105 

→ input to IC501-pin H4 → A/D conversion,

Gain adjustment by a built-in DSP of IC501.
Receiving signal input from IP Line 

→ Gain adjustment and D/A conversion by DSP of IC501 → output from IC501-pin E2 →

output to headset speaker.

+

-

AG2

R144

MICBIAS2

AG2

C164

AG2

OPBIAS2

AG2

R143

HESMIC2

HESSPOUT2

IC105

3

2

1

C168

R142

C161

C165

C169

C167

C166

C170

L112

C178

AG2

R137

R155

C160

CN101 CN205

2

3

C187

AG2

R140

R141

IC501

BBIC

R547

H4

E2

C221

C217

C218

JK202

1

4

2

3

5

C226

C205

D245

21

D247

21

D246

21

L210

L209

L208

10

11

AG

AG

C207

R223

HEADGND

ASIC

IC205

HEADGND

HEADGND

HEADGND

HEADGND

L212

AG

HEADGND