- RF Module: IC3
- PLL Oscillator
- Detector
- Compress/Expander
- Amplifier for transmission and reception
22.2. Power Supply Circuit/Reset Circuit
Circuit Operation:
When power on the Handset, the voltage is as follows;
BATTERY(2.2 V ~ 2.6V: TP3) TP14(4V) IC3(6, 27), D3 IC1(37) IC1(39, 63) (2.65V)
The Reset signal generates R19, C23 and 2.65V.
22.3. Charge Circuit
Circuit Operation:
When charging the handset on the Base Unit, the charge current is as follows;
DC+(5.5V ~ 6V) D4 R43, R44 (Base) (Handset) L4 Q2 F1
... Battery ... BATTERY- R21 GND L5 CHARGE-(Handset) CHARGE-
(Base) 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 Q2 of Handset.
Refer to Fig.101 in
Power Supply Circuit
().
22.4. 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 "
" starts flashing and
"battery alarm" starts ringing.
- Power Down
Battery voltage: V(Batt) < 2.2V
The BBIC detects this level and power down.
23. SIGNAL ROUTE
51
Summary of Contents for KX-TCD400GC
Page 46: ...18 FREQUENCY TABLE MHz 46 ...
Page 52: ...24 CPU DATA BASE UNIT 24 1 IC2 BBIC 52 ...
Page 56: ...45 MICP A I 56 ...
Page 60: ...60 ...
Page 61: ...28 CABINET AND ELECTRICAL PARTS LOCATION HANDSET 29 ACCESSORIES AND PACKING MATERIALS 61 ...
Page 62: ...30 TERMINAL GUIDE OF THE ICs TRANSISTORS AND DIODES 30 1 Base Unit 30 2 Handset 62 ...
Page 91: ...4 1 5 8 PbF 1 28 18 IC3 IC2 IC1 11 64 1 16 17 32 49 48 33 Marked ...
Page 93: ...Marked PbF IC1 IC2 100 80 5 8 4 1 50 51 30 31 1 11 18 1 28 IC3 ...