DOWNLOAD Panasonic KX-TGF310RUM / KX-TGF320RUM / KX-TGF320UCM / KX-TGFA30RUM Service Manual ↓ Size: 9.24 MB | Pages: 116 in PDF or view online for FREE

13

There are 2 pattern from power supply voltage.
1) AC adapter voltage is converted to VBAT(3.0V) at DCDC converter.
2) Battery voltage goes through to VBAT(Battery voltage).
VBAT is used for various voltage of the system.
Circuit Operation:

Startmonitor

(IC501 57pin)

VDD1 (1.8 V)

VBAT

Reset (RSTN) 
(IC501_77pin)

BBIC chip initialize

(CKM/STM)

AC adapter

+5.5V

Battery

Charge
Control

Circuit

DCDC

converter

IC302

VDD3

VBAT

Q301

VDD1

+1.8V

QSPI FLASH

IC502

TAM FLASH

IC601(KX-TGF320 only)

RF Part

DCDC

converter

VDD6

4.0V

LCD module

VDD4

3.0V_CP1

LEDs

BBIC

IC501

3.0V_CP2

VDD5

Sub IC

IC421

LCD bac

k

light

14

• Bell signal detection
• ON/OFF hook and pulse dial circuit
• Side tone circuit

In the idle mode, Q141 is open to cut the DC loop current and decrease the ring load. When ring voltage appears at the Tip (T)
and Ring (R) leads (When the telephone rings), the AC ring voltage is transferred as follows:
L1T 

 C105  R103  R110  R111 R112  BBIC pin18 (RINGING)

When the CPU (BBIC) detects a ring signal, Q141 turns on, thus providing an off-hook condition (active DC current flow through
the circuit). Following signal flow is the DC current flow.
T 

 D101  Q141  Q161  R163  D101  P101  R

Q141 is open, Q141 is connected as to cut the DC loop current and to cut the voice signal. The unit is consequently in an on-
hook condition.

Pin 19 of BBIC turns Q141 ON/OFF to make the pulse dialing.

Basically this circuit prevents the TX signal from feeding back to RX signal. As for this unit, TX signal feed back from Q161 is
canceled by the canceller circuit of BBIC.

C174

C171

R166

R178

RX
Pin25 of IC501

TX
Pin27 of IC501

R160

+

C161

C167

R165

R162

C173

R151

R164

C184

C103

C111

Q161

E

B

C

R163

R1

17

C1

15

R109

C109

Q141

Q142

C101

P101

L1T

L1R

D101

C102

1

2

3

+

~~

_

4

R145

C142

C152

R152

A

K

D142

R141

B

E

C

E

B

C

R142

SA101

R111

R101

HOOK
Pin19 of IC501

CIDOUT
Pin24 of IC501

LSRn
Pin28 of IC501

RINGING
Pin18 of IC501

CIDINn
Pin23 of IC501

CIDINp
Pin21 of IC501

R168

PARADET
Pin17 of IC501

ADC1
Pin33 of IC501

ADC0
Pin32 of IC501

R1

18

C1

16

R115

R116

R1

10

C1

10

R112

C113

C105

R103

C104

R102

C106

R104

15

• Audio Circuits and DTMF tone signal circuits.

Base Unit and Handset mainly consist of RF Module and DECT BBIC. 
Base Unit and Handset transmit/receive voice signal and data signal through the antenna on carrier frequency.

*Refer to Signal Route (P.21).

The voice signal input from the TEL LINE interface goes to DECT BBIC (IC501) as shown in Block Diagram (Base Unit_Main)
(P.8)
The voice signal passes through the analog part of IC501 where it is amplified and converted to a digital audio stream signal.
The burst switch controller processes this stream performing encryption and scrambling, adding the various other fields to
produce the GAP (Generic Access Profile) standard DECT frame, assigning to a time slot and channel etc.
In IC501, the carrier frequency is changing, and frequency modulated RF signal is generated.In IC501,RF signal is amplified,
and radiated from antenna. Handset detects the voice signal or data signal in the circuit same as the following explanation of
Receiver Block.

The signal of 1900 MHz band (1921.536MHz ~ 1928.448MHz) which is input from antenna is input to IC501 as shown in Block
Diagram (Base Unit_Main) (P.8).
In IC501, the signal of 1900 MHz band is downconverted to 864 kHz signal and demodulated, as GAP (Generic Access Profile)
standard DECT frames. It passes through the decoding section burst switch controller where it separates out the frame
information and performs de-encryption and de-scrambling as required. It then goes to the DSP section where it is turned back
into analog audio. This is amplified by the analog front end, and goes to the TEL LINE Interface.

During pulse dialling the hookswitch (Q141, Q142) is used to generate the pulses using the HOOK control signal, which is set
high during pulses. To force the line impedance low during the “pause” intervals between dial pulses, the PULSE_DIAL signal
turns on Q140.

16

MIP
MIN

HSSPOUTP

LOUT

HSMIP

HEADSET_DET

SPOUTP

SPOUTN

CKM//STM

CKM/STM

BBIC

RESET

CHG_CTL

BATTERY_ON

CHG_DET

WP, CLK, DATA

KEYSTOROBE_A~E

KEYIN_1~5

CHARGE

MIC

Receiver

Headset Jack

CN4

Monitor SP

LCD

CHARGE 
PUMP

KEYS

RF part

ANT1

X1

13.824 MHz

EEPROM

3V

BATTERY

LED
(LCD)

RSTN

VBAT

VBAT

3V

4.0V

VBAT

RXn

RXp

TXp

TXn

KX-TGFA30 BLOCK DIAGRAM (Handset)

KEY_LED

CP_OFF

Q6

LED

(KEY)

4V

CHARGE 
CONTROL

POWER SUPPLY
CONTROL