Circuit Operation (Base Unit) - Panasonic KX-TG9120FXS Service Manual

KX-TG9120FXS/KX-TGA910FXS
4.2.

Circuit Operation (Base Unit)

4.2.1. Outline
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: IC9
- Voice Prompt (TAM) D/L Area
- ICM/OGM/MEMO Recording Area
• TAM Companion: IC8
- Voice data compression and decompression
- Speaker Amp
- LED Driver
• Additionally,
- Power Supply Circuit (+3.3V, +2.5V, +1.8V output)
- Crystal Circuit (10.368MHz)
- Charge Circuit
- Telephone Line Interface Circuit
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