Panasonic KX-TG4021MET Service Manual

Contents

Panasonic KX-TG4021MET Service Manual Manual pdf 20 page image

20KX-TG4021MET/KX-TG4022MET/KX-TG4023MET/KX-TGA403MET4.7. Circuit Operation (Handset)4.7.1. OutlineHandset consists of the following ICs as shown in Block Diagram (Handset) (P.18).• DECT BBIC (Base Band IC): IC1- All data signals (forming/analyzing ACK or CMD signal)- All interfaces (ex: Key, Detector Circuit, Charge, DC/DC Converter, EEPROM, LCD, RF Power Amp.)- PLL Oscillator- Detector- Compress/Expander- Reception• RF Power Amp: IC801- Amplifier for transmission• EEPROM: IC3- Temporary operating parameters (for RF, etc.)4.7.2. Power Supply Circuit/Reset CircuitCircuit Operation:When power on the Handset, the voltage is as follows;BATTERY(2.2 V ~ 2.6 V: BATT+) → F1 → Q2 (1.8 V), IC1-43pin (2.5V)The Reset signal generates IC1 (61 pin) and 1.8 V.