
10.7. DXDP COMMUNICATION
Function
This circuit performs the same communication as DXDP-compatible DPT and PBX
communication connected with DXDP port.
Circuit Operation
The data to Slave DPT is outputted from pin 33 and 34 of IC2 and sent by Transistor Q2 and Q3.
The data from Slave DPT is inputted to the comparator (pin 31) built in IC2.
The threshold voltage of the comparator is determined by R112 to 114 and inputted to pin 30
and 32 of IC2.
Also, the supplying power to Slave DPT is controlled by a constant current circuit of Q16 as
below.
- IC2-pin 28 as H : Constant current circuit ON
- IC2-pin 28 as L : Constant current circuit OFF
- IC2-pin 29 as H : 40mA Feeding (Slave DPT usually)
- IC2-pin 29 as L : 20mA Feeding (Slave DPT at starting up only)
19
Содержание KX-T7665NE
Страница 4: ...4 ...
Страница 6: ...1 Remove the Stand 2 Remove 5 Screws A 3 Remove the Cabinet Cover 6 ...
Страница 9: ...8 1 NO OPERATION Note Refer to 1 4 of WAVEFORM for waveform 8 2 LCD DOES NOT OPERATE 9 ...
Страница 10: ...Note Refer to 5 of WAVEFORM for waveform 8 3 HANDSET DOES NOT WORK Receive Send 10 ...
Страница 11: ...Note Refer to 6 7 of WAVEFORM for waveform 8 4 SPEAKER PHONE TROUBLE Receive Send 11 ...
Страница 14: ...LCD Contrast Control CONTRAST IC6 Pin 59 IC6 Pin19 HIGH L L MIDDLE Z L LOW Z Z 14 ...
Страница 26: ...13 CABINET AND ELECTRICAL PARTS LOCATION 26 ...
Страница 27: ...14 ACCESSORIES AND PACKING MATERIALS 27 ...
Страница 28: ...28 ...
Страница 44: ... 8 7 Pin31 of IC2 Communication waveform Pin8 and 10 of IC4 PCM interface waveform between IC4 and IC3 ...