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KX-TGA807/809 BLOCK DIAGRAM (HANDSET)

6

3.3V

18

4

20

6, 58, 69, 81

49

22, 23

67, 68

66

Q1, Q6

76

Q3

41

40

7

44, 45

37, 38

3, 81, 83 - 88

R-D

A

T

A

T

-D

ATA

Q13, Q15

Q5

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The handset consists of Base Band Controller, charger, regulator, LCD, EEPROM, RF module, keypad, crystal, speaker ampli-
fier, speaker, earpiece, ringer & microphone, and so on.

BBIC (U7) controls all functions of the handset. This device includes all control circuits of the handset for RF module, LCD con-
troller, keypad interface, earpiece, microphone, ADPCM codec, switching and series regulator and so on.

The base unit supplies DC 6V power to the charger and the charger charges the batteries to use this power. The signal on the
charger circuit is generated when the handset is being charged, and this signal is used to control the charger circuit and for
automatic off-hook by cradle-off when an incoming call is coming.

The battery is (2.4V / 2 cell) directly supplied to switching regulator which is controlled by base band controller and step up the
DC 3.3V to the RF module & I/O port. DC 2.5V & DC1.8V are used for the base band and the circumference circuits.

This is 256K bits memory. The each kind of value to set-up at power-on, redial memory, speed-dialing memory, and so on are
stored in this device.

Receiver part: RF signals induced at the antenna are extracted by the RF control interface. The RF signal to be selected is
demodulated into RX_DATA signals. And the signals are passed to the base band controller.
Transmitter part: The signal from transceiver chip-set is fed to the antenna through the RF power amplifier by control of the RF
control interface. And then this signal is radiated from antenna.
Logical part: The frequency to be used is generated in transceiver chip-set by control signals (CLK, DATA, ENABLE, SYRI) of
the RF control interface.

The keypad consists of 12 dialing keys and 11 function keys.

U2 forms a audio power amplifier for speakerphone and ringer.

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• BU: Base Unit
• HS: Handset

Rx audio signal from line interface is received at “LINERX_P” path into the BU MCU (pin 45) and then signal from the BU RF is
transformed, and the HS RF receives the signal and forwards it to MCU, and the signal received at the HS MCU (pin 40, 41) is sent
to receiver.

Tx audio signal from MIC is received at mic path into the HS MCU and then audio signal from the HS RF is transformed, and the BU
RF receives the signal and forwards it to MCU, and the BU MCU receives the audio signal from Pin 40 at “LINETX_P” path and
transmits it to line interface out of PSTN.

Rx signal from line interface is received at “LINERX_P” path into the BU MCU (pin 45) and then signal from the BU RF is trans-
formed, and the HS RF receives the signal and forwards it to MCU, and the signal received at the HS MCU (pin 40, 41) is sent to
speaker phone IC (U2) to be amplified for speaker output.

Tx audio signal from MIC is received at mic path into the HS MCU and then audio signal from the HS RF is transformed, and the BU
RF receives the signal and forwards it to MCU, and the BU MCU receives the audio signal from Pin 40 at “LINETX_P” path and
transmits it to line interface out of PSTN.

Telephone line catches ringer signal from tip ring into base unit, and then the base transistor Q8 turns on and ringer data signal for
the BU MCU (Pin 54) is detected and the handset speaker/base buzzer produces “Melody tone”.

CID signal from tip ring is coupled at (CID1_P, CID1_N) paths and the BU MCU (Pin 37, 38) detects it, then Handset display shows
the telephone no.

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