Panasonic KXTG2226W - 2.4GHZ DIGITAL PHONE, Service Manual

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The DTMF detection is implemented by the DSP system in
software. The DTMF detection is performed during Record,
Playback, and Line Monitoring modes of operation.
When the DTMF data from the Handset is received, the DTMF
signal is output.
- Synthesized Voice (Pre-recorded message)
The DSP implements synthesized Voice, utilizing the built in
speech detector and an FLASH MEMORY, which stored the
vocabulary.
- Caller ID and Call Waiting CID demodulation
The DSP implements monitor and demodulate the FSK signals that
provide CID information from the Central Office.
- Analog Switching
The voice signal from telephone line is transmitted to the speaker
or the voice signal from speakerphone microphone is transmitted
to the Telephone line, etc. They are determined by the signal path
route operation of voice signal.
- Block Interface Circuit
RF unit, LED, Key scan, Speaker, Microphone, Telephone line, LCD
17.2. Flash Memory (IC300)
Following information data is stored.
- Voice signal
ex: Pre-recorded Greeting message, Incoming message
- Telephone number, etc.
ex: Telephone Directory number, Caller ID data, ID code
- Settings
ex: message numbers, caller ID numbers, pulse tone dial
17.3. Power Supply Circuit
Function:
The power supply voltage from AC adaptor is converted to the desired voltage of each block.
Circuit Operation:
This unit supplies the voltage to each block as shown below.
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