Panasonic KX-TA1232, Service Manual

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Function Description
Generating DC voltage Gen15, -15 and +5.3 V from AC power or the batteries.
Capacities:
- +5.3 V, 3.0 A
- +15 V, 4.7 A
- -15 V, 4.5 A
Bell Amp It increases the bell signal from CPU CARD, and sends to the EXT CARD.
(2) CPU BOARD
CPU BOARD covers the CPU function which controls the system and TSW (time sw.) function
which exchanges the PCM lines as the main functions. In addition, it is equipped with the
common resources such as the conference function, the clock function, and the clock generator
function.
Function Description
CPU function Controls the general system according to the programs.
TSW function Exchanges the PCM lines following the control from CPU.
Conference function Allows the conference call of 3-person × 6-conference.
Clock function The clock LSI backed up by batteries realizes the clock function in the
system.
Tone generator Generates 4 types of the call progress tone and 2 channels of the DTMF
tones.
Holding tone source Internal holding tone source (optical for the derivative models).
External holding tone source: 2 channels.
External paging function Output function for 2 channels of the external pagings.
Serial I/F function RS-232C port: 1 port
Clock generator function Generates the clock for PCM highway system and supplies it to the system.
Voltage watching Watches the voltages of +5 V and +15 V, resets the system if +5 V is derated.
Back-up function Back up the CPU peripherals (+5.3 V) for 1 second or more during the power
failure.
Back up the system data in RAM and the clock IC for 7 years by the lithium
battery.
Bell signal generator
function 25 Hz signals are generated by the CPU and filter circuit.
(3) BASIC CO BOARD
BASIC CO BOARD functions the interface between the system and the lines. 8 lines per one CO
board are covered.
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