Panasonic KX-A227X, Service Manual

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10 EXPLANATION OF BLOCK DIAGRAM
10.1. MAIN UNIT (KX-TES824LA/KX-TEM824LA)
10.1.1. Power Supply Circuit
This power supply unit is a switching power supply. Power supply unit supplies DC voltage (+27V,+15V,-15V,3.3V) to main board
and other optional cards. And this unit has an adaptor circuit to back up battery. And this unit amplified the BELL signal (20/25Hz
sign wave outputted from the ASIC) and supply bell signal to the telephone.
10.1.2. COL Interface Circuit
There are the interface circuits linking the CO line (CO1 -CO3) and the cross point circuit section.
In case of KX-TEM824, the system has 6CO line (CO1 - CO6).
10.1.3. Cross Point Circuit
This is a space division switching system for connecting the following:
The eight extension circuits with the eight CO, DTMF generator, DTMF receiver, INT-CALL ID, MODEM, OGM, VB, paging, music
on hold, tone etc.
It is composed of 3 C-MOS IC´s. (8 X 16 matrix: 2pcs and 4 X 8 matrix: 1pce).
*In case of KXTEM824, the system has 6 C-MOS IC´s (8 X 16 matrix: 3pcs and 4 X 8 matrix: 2pce, 8 X 8 matrix: 2pce).
10.1.4. Intercom Circuit
This is the interface circuit of the single line telephone, and it is composed of 8 intercom circuit (ICM1-8) In case of KX-TEM824,
the system has 16 intercom circuits(ICM1-16).
10.1.5. Power Failure Through Call Switching Circuit
KXTES824 have one power failure transfer circuit (CO1-EXT101).
In case of KXTEM824,the system has 2 power failure circuit (CO1-EXT101 CO4 -EXT109).
10.1.6. Data Communication Circuit
The APT i/f module which performs communication with a private telephone machine is built in ASIC.
8ch are controlled per block. Control of 3 blocks (24ch) is possible for ASIC at the maximum.
10.1.7. Control Circuit
A control block consists of only the [ASIC] CPU (compatibility with Intel 8086) (IC700), Flash ROM (8Mbit) (IC705), SRAM (4Mbit)
(IC704), and PIO ASIC (IC6). PIO ASIC mainly performs extension control and PIO built in ASIC CPU mainly performs extension
control. RTC (Real Time Clock) and SRAM inside CPU are backed up by the lithium battery in order to hold time, system data, etc.
10.1.8. Tone Generator Circuit
The rectangle wave generated by the timer of ASIC is changed into sine wave with a low path filter, and various tones are
generated.
10.1.9. DTMF Generator Circuit
A DTMF generator is used for dispatch to outside line, and communication with the voice mail connected to the extension.
10.1.10. DTMF Receiver Circuit
The circuit which receives the Dial Tone Multi Frequency by which extension dispatch is carried out with the DTMF receiver
connected to the crossing point.
10.1.11. Int Call ID Circuit
FSK/Dial Tone Multi Frequency generated by DSP in ASIC are connected even to a crossing point through AMP. The circuit which
sends out a CALLID signal to the telephone connected to an extension by connecting the line of INT-CALL-ID with arbitrary
extensions.
10.1.12. Modem Circuit
The MODEM signal generated by DSP in ASIC is connected even to a crossing point through AMP.
The circuit which connects the line of MODEM with arbitrary outside line, and enables MODEM communication with outside line.
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KX-TES824LA / KX-TEM824LA /