Circuit Operation (Handset); Outline; Power Supply Circuit/Reset Circuit - Panasonic KX-TG4221N Service Manual

4.7.

Circuit Operation (Handset)

4.7.1.

Outline

Handset consists of the following ICs as shown in Block Diagram (Handset) (P.19).
• DECT BBIC (Base Band IC): IC5
- All data signals (forming/analyzing ACK or CMD signal)
- All interfaces (ex: Key, Detector Circuit, Charge, EEPROM, LCD.)
- PLL Oscillator
- Detector
- Compress/Expander
- Reception
• EEPROM: IC3
- Temporary operating parameters (for RF, etc.)
4.7.2.

Power Supply Circuit/Reset Circuit

Circuit Operation:
When power on the Handset, the voltage is as follows;
BATTERY(2.2 V ~ 2.6 V: BATT+)  F1  Q2 (1.8 V), IC5-49pin (3.0V)
The Reset signal generates IC5 (68 pin) and 1.8 V.
Battery +
1.8 V
Reset
(IC1_61pin)
KX-TG4221N/KX-TG4222N/KX-TG4223N/KX-TG313SK/KX-TG4224N/KX-TG4225N/KX-TGA421N
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