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EEPROM, LCD)
- RF Module: IC10
- PLL Oscillator
- Detector
- Compress/Expander
- Amplifier for transmission and reception
23.2. Power Supply Circuit/Reset Circuit
Circuit Operation:
When power on the Handset, the voltage is as follows;
BATTERY(2.2 V ~ 2.6V: TP3)
(2.65V)
The Reset signal generates IC1,C58 and 2.65V.
23.3. Charge Circuit
Circuit Operation:
When charging the handset on the Base Unit, the charge current is as follows;
DC+(5.5V ~ 6V)
D4
BATTERY+ ... Battery ... BATTERY-
GND
DC-(GND)
In this way, the BBIC on Handset detects the fact that the battery is charged.
The charge current is controlled by switching Q7 of Handset.
Refer to Fig.101 in
Power Supply Circuit
23.4. Battery Low/Power Down Detector
Circuit Operation:
"Battery Low" and "Power Down" are detected by BBIC which check the voltage from battery.
The detected voltage is as follows;
- Battery Low
Battery voltage: V(Batt) < 2.3V
The BBIC detects this level and "
"battery alarm" starts ringing.
- Power Down
Battery voltage: V(Batt) < 2.2V
The BBIC detects this level and power down.
23.5. Speakerphone and Headset Jack
+4V(4V)
IC10(6, 27), D20
R43, R44
L4
CHARGE+(Base)
R14
().
IC1(35)
CHARGE+(Handset)
GND
CHARGE-(Handset)
" starts flashing and
68
IC1(37, 22, 1, 84, 61)
Q7
CHARGE-(Base)
F1
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