Panasonic KX-TGH262B - Handset Circuit Operation; Handset Power Supply and Reset

22
KX-TGH260/KX-TGH262/KX-TGH263/KX-TGH264/KX-TGHA20/KX-TGA20
4.8. Circuit Operation (Handset)
4.8.1. Outline
Handset consists of the following ICs as shown in Block Diagram (Handset) (P.20).
• DECT BBIC (Base Band IC): IC1
- All data signals (forming/analyzing ACK or CMD signal)
- All interfaces (ex: Key, Detector Circuit, Charge, EEPROM, LCD)
• EEPROM: IC3
- Setting data is stored. (e.g. ID, user setting)
4.8.2. Power Supply Circuit/Reset Circuit
Circuit Operation:
When powering on the Handset, the voltage is as follows;
BATTERY(2.2 V ~ 2.6 V: BATT+) → F1 → BBIC (IC1) 32 pin
The Reset signal generates IC1 (71 pin) and 1.8 V.
Start monitor
(IC1 50 pin)
1.8 V
VBAT
Reset (*RST)
(IC1_71 pin)
BBIC chip initialize
(STM)
GND
BATTERY
2CELL
BBIC
3.0V
3.0V
Charge Pump Output
For all peripherals
3.0V3.0V
EEPROM
GND
KEY LED
4.0V
VBAT
1.8V
3.0V3.0V
LCD
4.0V
4.0V 1.8V