Circuit Operation (Handset) - Panasonic KX-TH1211B Service Manual

KX-TH1211B/KX-TH1212B/KX-TGA930T

4.12. Circuit Operation (Handset)

4.12.1. Construction
The circuit mainly consists of DSP and RF part as shown in the block diagram.
4.12.1.1. 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 20 ms under normal conditions.
4.12.1.2. RF part
Mainly voice signal is modulated to RF, or it goes the other way.
4.12.1.3. EEPROM: IC541
Setting data is stored.
ex: ID code, user setting
28