6.1.11. BATTERY SUPPLY (SEE Fig. 27)
A switch mode boost converter is used to provide a 3.8V supply from the battery. This supply is sensed by the BBIC through
pin 26 (TP14) so that the switching rate can be controlled by a FET (T3) driven from pin 24 (TP13). A resistor on the Source
of the FET provides a current sense at pin 25 (TP12).
T3 switches the current through L1. When T3 switches off the back emf conducts through D16 and charges the reservoir cap
C4.
6.1.12. 2.65V REGULATOR (SEE Fig. 27)
A 2.65V supply is provided for the BBIC and is regulated by the BBIC’s on board control signal LRB (pin 37).
This reference is fed to the base of T6 to keep the “VREG+” line at 2.65V.
6.1.13. BATTERY CHARGING CIRCUIT (SEE Fig. 27)
The supply for the battery comes from the charge terminals at J3 and J4. Battery charge rate is controlled by switching the
current through T7 such that the average charging current is 170mA. The current flow is monitored at pin 49 of the BBIC by
measuring the voltage across R56.
D21 protects against the high voltage present on the charge contacts (J3 and J4) when there is no battery in the handset. R42
and C50 provide a signal to the BBIC (pin 27) to detect that the handset has been placed on the base charger.
Circuit Diagram
29
KX-TCD705RUM / KX-TCD705RUS
Содержание KX-TCD705RUM
Страница 4: ...1 LOCATION OF CONTROLS 1 1 Base Unit 1 2 Handset 4 KX TCD705RUM KX TCD705RUS ...
Страница 7: ...2 1 Assembly the LCD to P C Board Handset 7 KX TCD705RUM KX TCD705RUS ...
Страница 12: ...4 6 Handset Programming 4 6 1 Change the Initial Settings 12 KX TCD705RUM KX TCD705RUS ...
Страница 13: ...13 KX TCD705RUM KX TCD705RUS ...
Страница 14: ...14 KX TCD705RUM KX TCD705RUS ...
Страница 16: ...4 7 4 Select the Dialling Mode 4 7 5 Cancelling a Handset 4 7 6 Reset Base Unit 16 KX TCD705RUM KX TCD705RUS ...
Страница 19: ...Circuit Diagram KX TCD705RUM KX TCD705RUS 19 ...
Страница 24: ...6 CIRCUIT OPERATION HANDSET BLOCK DIAGRAM BASEBAND SECTION HANDSET 24 KX TCD705RUM KX TCD705RUS ...
Страница 27: ...Circuit Diagram 27 KX TCD705RUM KX TCD705RUS ...
Страница 36: ...9 TROUBLESHOOTING GUIDE 9 1 HANDSET DOES NOT OPERATE 36 KX TCD705RUM KX TCD705RUS ...
Страница 37: ...9 2 HANDSET LINK 37 KX TCD705RUM KX TCD705RUS ...
Страница 38: ...38 KX TCD705RUM KX TCD705RUS ...
Страница 39: ...9 3 HANDSET DOES NOT LINK 39 KX TCD705RUM KX TCD705RUS ...
Страница 40: ...9 4 BATTERY DOES NOT CHARGE 9 5 NO VOICE RECEPTION 40 KX TCD705RUM KX TCD705RUS ...
Страница 41: ...9 6 NO VOICE TRANSMISSION 41 KX TCD705RUM KX TCD705RUS ...
Страница 42: ...9 7 BASE UNIT DOES NOT LINK 42 KX TCD705RUM KX TCD705RUS ...
Страница 43: ...9 8 BASE UNIT CALLER ID PROBLEMS 43 KX TCD705RUM KX TCD705RUS ...
Страница 44: ...10 CABINET AND ELECTRICAL PARTS LOCATION BASE UNIT 44 KX TCD705RUM KX TCD705RUS ...
Страница 45: ...11 CABINET AND ELECTRICAL PARTS LOCATION HANDSET 45 KX TCD705RUM KX TCD705RUS ...
Страница 46: ...12 ACCESSORIES AND PACKING MATERIALS 46 KX TCD705RUM KX TCD705RUS ...
Страница 71: ...16 3 RF module IC1 3 4 5 6 7 2 1 IC402 72 KX TCD705RUM KX TCD705RUS ...
Страница 75: ...17 2 RF Section IC402 3 4 5 2 1 76 KX TCD705RUM KX TCD705RUS ...
Страница 76: ...IC400 IC402 3 4 5 2 1 KX TCD705RUM KX TCD705RUS SCHEMATIC DIAGRAM HANDSET RF Unit 77 KX TCD705RUM KX TCD705RUS ...
Страница 80: ...19 2 Flow Solder Side View KX TCD705RUM KX TCD705RUS 82 ...