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KX-TG6440PK/KX-TGA641S/KX-TGA641T/KX-TGA740B
4.7.
Circuit Operation (Handset)
4.7.1.
Construction
The circuit mainly consists of DSP and RF part as shown in the block diagram.
4.7.1.1.
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.
4.7.1.2.
RF part
Mainly voice signal is modulated to RF, or it goes the other way.
4.7.1.3.
EEPROM: IC541
Setting data is stored.
ex: ID code, user setting
Summary of Contents for KX-TG6440PK
Page 2: ...2 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B ...
Page 28: ...28 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B 4 10 Signal Route ...
Page 29: ...29 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B RF part signal route ...
Page 31: ...31 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B 5 2 Display ...
Page 35: ...35 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B ...
Page 36: ...36 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B 7 1 2 Programming using the Direct Commands ...
Page 37: ...37 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B ...
Page 38: ...38 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B 7 2 Error Messages ...
Page 39: ...39 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B 7 3 Troubleshooting ...
Page 40: ...40 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B ...
Page 41: ...41 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B ...
Page 42: ...42 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B ...
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Page 67: ...67 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B 11 1 2 Handset ...
Page 68: ...68 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B 11 1 3 Charger Unit ...
Page 69: ...69 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B 11 2 How to Replace the Handset LCD ...
Page 89: ...89 KX TG6440PK KX TGA641S KX TGA641T KX TGA740B Memo ...