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(BBIC, Flash Memory, EERROM) is a digital speech/signal processing system that implements all the functions of speechcom-
pression, record and playback, and memory management required in a digital telephone answering machine.The BBIC system
is fully controlled by a host processor. The host processor provides activation and control of all that functions as follows.

• Voice Message Recording/Play back

The BBIC system uses a proprietary speech compression technique to record and store voice message in Flash Memory.An
error correction algorithm is used to enable playback of these messages from the Flash Memory.

• DTMF Generator

When the DTMF data from the handset is received, the DTMF signal is output.

• Synthesized Voice (Pre-recorded message)

The BBIC implements synthesized Voice, utilizing the built in speech detector and a Flash Memory, which stored the vocabulary.

• Caller ID demodulation

The BBIC implements monitor and demodulate the FSK/DTMF signals that provide CID information from the Central Office.

• Digital Switching

The voice signal from telephone line is transmitted to the handset or the voice signal from the handset is transmitted to theTele-
phone line, etc. They are determined by the signal path route operation of voice signal.

• Block Interface Circuit

RF part, LED, Key scan, Speaker, Telephone line.

Following information data is stored.

• Voice signal

ex: Pre-recorded Greeting message, Incoming message

Following information data is stored.

• Settings

ex: message numbers, ID code, Flash Time, Tone/Pulse

• 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:
R 

 P101  R111  C111  Q111  BBIC pin 5

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

RF part

ADPCM

Analog
Front
End

&
  
Multi-
plexer

TEL
Line
Interface

Digital
Speech
Processor

Caller ID
Modem

Digital TAM  System

Flash Memory  IC601

 Host CPU

DECT RF system
 TDMA/TDD
 Mod/Demod
 PA/LNA

ADPCM

SW1/ Charge

EEPROM IC611

12

throughthe circuit). Following signal flow is the DC current flow.
T 

 D101  Q141  Q161  R168  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 6 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.

The power supply voltage from AC adaptor is converted to VBAT (3.0V) in 3.0V DC/DC Converter (IC301,Q301) and +3.0V for
peripherals and analog part is insulated from VBAT by Doubler of BBIC.
Circuit Operation:

6.5V

VB AT

RSTN(Reset) 

pin 54

VB AT

pin 10

pin 57

pin 9

pin 15

IC501

IC301,Q301

IC601

BBIC

DOUBLER OUT
F or pe ripherals

VDDC (1.2V)

AC Adaptor

        3.0V
DC/DC
CONVERTER

FLASH

IC611

EEP R OM

+3.0V

STM/CKM

Recei ve

Amp.

RF P art

Sta rtmonitor

(IC501 57pin)

VDDC (1.2  V)

VB AT

Reset (RSTN) 
(IC501_54 pin)

BBIC chip initiali ze

(CKM/STM)

13

The voltage from the AC adaptor is supplied to the charge circuits.

The caller ID is a chargeable ID which the user of a telephone circuit obtains by entering a contract with the telephone company
to utilize a caller ID service. For this reason, the operation of this circuit assumes that a caller ID service contract has been
entered for the circuit being used. 
The Caller-ID data from exchange is supplied to the telephone using either method of FSK or DTMF. The method is chosen
according to the exchange of telephone office. This unit is available to receive the data with both methods and displays the
received data on LCD.

• FSK (Frequency Shift Keying) format

• DTMF format

It is the method to send the telephone number of calling party with DTMF to the telephone. DTMF is sent before the first bell sig-
nal.
The data is sent in turn; first the start code, secondly the telephone number of calling party, lastly end code.
The DTMF is chosen from A (1633 Hz and 697 Hz), B (1633 Hz and 770 Hz), C (1633 Hz and 852 Hz) and D (1633 Hz and 941
Hz) as the start code and end code according to the exchange.

D362

R37

2

R371

CHARGE+

F301

DCP

CHARGE-

+6.5V

DCM

STD Ring / 20Hz
Tip-Ring

FSK

DATA in

1st Ring

Silent interval

2nd Ring

DATA

0.1Vrms

70Vrms

1300Hz or
1200Hz
=DATA "1"

2100Hz or
2200Hz
=DATA "0"

Startcode

Endcode

Calling party's 
telephone number

DTMF

1st Ring

0.1Vrms

70Vrms

14

SPEAKER

RECEIVER

MIC

CHARGE

CIRCUIT

Q4, Q6

Q9, R8Q

9

, R

8

CHARGE(+)

CHARGE_C

TRL

CHARGE_DE

T

EEP

R

OM

SCL

SD

A

R45

VB

A

T

BA

T

T

-

1.8

 V

Q2

1.8

 V

CP 3.0

 V

LC

D

CD

RESE

T

CSB

SD

A

 SCL

CPU

Analog

F

ront

End

D/A

A/D

37

35

25

24

21

20

34

33

63

64

 42

27

48

49

69

60

61

72

ADPCM

C

odec

Filt

er

DSP

Speech

Dec

oding

Speech

Enc

oding

BMC

Burst

Dec

oding

ANT1

Burst

Enc

oding

RF 

PLL

MOD/DEMOD

2

3

87

86

RXn

ANT1

RXp

TX

p

TX

n

9

10

XT

A

L

X1

10.368

MH

z

BA

T

T

E

R

Y

50

ON SWIT

CH

KEY

P

AD

Char

ge

Pu

m

p

RO

W

S

C

O

LUMNS

CP3V

CP3.0V

CP_LED

54, 55, 56, 57

14, 15, 16, 17, 52

BBIC

 62

LDO_C

TRL

CP3V

71

CHARGE

C

ONT

A

C

T

S

BA

T

TER

Y

T

ERMINAL

KX

-T

GA251 BL

OCK DIA

GRAM (Handset)

BA

T

T

ER

Y_ON