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There are several types of PbF solder available commercially. While this product is manufactured using Tin, Silver, and Copper
(Sn+Ag+Cu), you can also use Tin and Copper (Sn+Cu) or Tin, Zinc, and Bismuth (Sn+Zn+Bi). Please check the manufacturer’s
specific instructions for the melting points of their products and any precautions for using their product with other materials. 
The following lead free (PbF) solder wire sizes are recommended for service of this product: 0.3 mm, 0.6 mm and 1.0 mm.

When discarding P. C. Board, delete all personal information such as telephone directory and caller list or scrap P. C. Board.

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• Specifications are subject to change.

• Operation range: Up to 300 m outdoors, Up to 50 m indoors, depending on the condition.
• Analog telephone connection: Telephone Line

7

Analog

Front

End

To TEL_LINE

A

B

CN1

Bridge

Rect

 D3 D3

Hook Switch

Q

4

,Q

5

Audio

Bell/Caller ID

Interface

CPU

59

54

61

52

60

56

55

BELL

HOOK

Off-Hook Line Voltage

64 ADCO

A/D

D/A

ADPCM

Codec Filter

DSP

Speech Encoding

Speech Decoding

BMC

Burst Encoding

Burst Decoding

RF

Interface

18

19

TXDA

RXDA

21

20

22

SYCL

SYDA

SYEN

ANT1

ANT2

RF Module

18

16

2

31

8

21

14

13

12

12

13

XTAL

X

1

10.368

MHz

EEPROM

SCL

SDA

6

5

7

To AC Adaptor

CN2

Limit

Resistor

Charge

Detector

CHARGE

CONTACT

(Optional)

VUNREG

3.3V

Reg.

IC

1

2.5V

Reg.

Q

9

1.8V

Reg.

Q

8

3.3 V

2.5 V

1.8 V

BBIC

FLASH

MEMORY

(TAM)

TAM Companion IC

RESET

CS

CS

3

4

2

1

8

SCK

SI

SO

9

14

16

39

40

38

36

37

62

10

11

23

12

KX-TG7227/7228 BLOCK DIA

GRAM 

(BASE UNIT)

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Base unit consists of the following ICs as shown in Block Diagram (Base Unit) (P.7).

• DECT BBIC (Base Band IC): IC7

- Handling all the audio, signal and data processing needed in a DECT base unit
- Controlling the DECT specific physical layer and radio section (Burst Module Controller section)
- ADPCM code filter for speech encoding and speech decoding (DSP section)
- Echo-cancellation and Echo-suppression (DSP section)
- Any tones (tone, sidetone, ringing tone, etc.) generation (DSP section)
- DTMF receiver (DSP section)
- Clock Generation for RF Module
- ADC, DAC, timer, and power control circuitry
- All interfaces (ex: RF module, EEPROM, LED, Analog Front End, etc.)

• RF Module: IC10

- PLL Oscillator
- Detector
- Compress/Expander
- First Mixer
- Amplifier for transmission and reception

• EEPROM: IC5

- Temporary operating parameters (for RF, etc.)

• FLASH MEMORY: IC11

- Voice Prompt (TAM) D/L Area
- ICM/OGM Recording Area

• TAM Companion: IC8

- Voice data compression and decompression
- Speaker Amp
- LED Driver

• Additionally,

- Power Supply Circuit (+3.3 V, +2.5 V, +1.8 V output)
- Crystal Circuit (10.368 MHz)
- Charge Circuit
- Telephone Line Interface Circuit