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8
KX-TCA275CE
4.2.
Circuit Operation (Handset)
4.2.1.
Outline
Handset consists of the following ICs as shown in Block Diagram (Handset)
(
P.7
).
• BBIC (Base Band IC): IC3
- All data signals (forming/analyzing ACK or CMD signal)
- All interfaces (ex: Key, Detector Circuit, Charge, LCD, LED, SRAM, Flash ROM)
• SRAM: IC1
- Application data and code are temporarily stored.
• Flash ROM (substitute EEPROM): IC2
- Source program data and temporary user data are stored.
• AMPLIFIER IC: IC5
- Single OP_AMP for SPEAKER
• RF Module:
- PLL Oscillator
- Detector
- Compress/Expander
- Amplifier for reception
- Amplifier for transmission
4.2.2.
Power Supply Circuit/Reset Circuit
When power on the Handset, the voltage is as follows;
BATTERY(3.5 V to 4.2V: )
→
Q8 (1.8V)
→
Q10 (3.0V)
The reset signal is generated with IC3 and Q17.
Power for RF IC (IC601) is generated with IC603.
5.0V for LCD back-light is generated with IC4.
Battery (3.5V to 4.2V) is used for RF Module, Amplifier IC (IC5), Vibrator, DC/DC Converter (IC4).
1.8V is used only for BBIC (IC3).
3.0V is used for BBIC (IC3), LCD, SRAM (IC1), Flash ROM (IC2), Red LED, Green LED, Key back-light.
Summary of Contents for KX-TCA275CE
Page 15: ...15 KX TCA275CE 5 Location of Controls and Components 5 1 Handset ...
Page 16: ...16 KX TCA275CE ...
Page 19: ...19 KX TCA275CE 7 Operating Instructions 7 1 Soft Keys ...
Page 20: ...20 KX TCA275CE ...
Page 21: ...21 KX TCA275CE 7 2 Handset Setting Menu Layout ...
Page 23: ...23 KX TCA275CE 7 5 DISPLAY ...
Page 25: ...25 KX TCA275CE 7 7 Function Keys ...
Page 26: ...26 KX TCA275CE 7 8 Flexible Keys ...
Page 27: ...27 KX TCA275CE 7 9 Caller ID ...
Page 28: ...28 KX TCA275CE 7 10 Character Mode Table ...
Page 31: ...31 KX TCA275CE Charger Unit NO Display On the LCD ...
Page 32: ...32 KX TCA275CE 5V Circuit 8 2 Battery Charge Trouble Handset 8 2 1 Charge On ...
Page 33: ...33 KX TCA275CE 8 2 2 Charge Off ...
Page 34: ...34 KX TCA275CE 8 3 LED Trouble Handset 8 3 1 Key Back Light 8 3 2 Charging And Ringing LED ...
Page 36: ...36 KX TCA275CE 8 6 No Voice Transmission ...
Page 37: ...37 KX TCA275CE 8 7 No Voice Reception 8 7 1 Talk Mode ...
Page 39: ...39 KX TCA275CE 9 Service Fixture Tools ...
Page 46: ...46 KX TCA275CE 4 6 Downloading Start After several seconds Display shows Flash Program Start ...
Page 65: ...65 KX TCA275CE 16 2 Cabinet and electrical Parts Location 16 2 1 Handset ...
Page 66: ...66 KX TCA275CE 16 2 2 Charger Unit ...
Page 67: ...67 KX TCA275CE 16 2 3 Accessories and Packing Materials ...