Circuit Operation (Handset) - Panasonic KX-TG3531BXS Service Manual

KX-TG3531BXS/KX-TG3531BXB/KX-TG3532BXS/TG3532BXB/KX-TGA351S/KX-TGA351B
4.8.

Circuit Operation (Handset)

4.8.1. Construction
The circuit mainly consists of DSP and RF part as shown in the block diagram.
4.8.1.1. DSP: IC501
Function
• Battery Low, Power down detect circuit
• Ringer Generation
• Interface circuit
RF part, Speaker, Mic, LED, Key scan, LCD, Headset
Initial waves
Note:
(*1) The initializing time of the DSP chip is 20ms under normal conditions.
4.8.1.2. RF part
Mainly voice signal is modulated to RF, or it goes the other way.
4.8.1.3. EEPROM: IC541
All setting data is stored.
ex: ID code, user setting (Phonebook, Caller ID data)
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