Panasonic KX-TEA308RU / KX-TE82460X / KX-TE82492X / KX-TE82493X / KX-A227X Service Manual ▷ View online
11.5. POWER FAILURE THROUGH CALL SWITCHING CIRCUIT
11.5.1. Circuit operation
If an AC power failure lasts longer than one second (momentary power failure), the COL is directly connected to the extension.
The COL1 will be connected with EXT101.
The COL1 will be connected with EXT101.
11.6. DATA COMMUNICATION CIRCUIT
11.6.1. Composition
This circuit is composed of the ASIC and the data communication interface circuits for the ICM circuit.
11.6.2. Circuit Operation
1) Data Communication of CPU (IC700)
The APT i/f module is built into CPU.
An RX/TX couple signal is shared by eight APT communications; this communicates via the selection signal.
That is, in the APT i/f module, extension 1-8 port switch the port communicates every 4ms respectively with
#101
An RX/TX couple signal is shared by eight APT communications; this communicates via the selection signal.
That is, in the APT i/f module, extension 1-8 port switch the port communicates every 4ms respectively with
#101
→#102→#103→#104..... →#108→#101.....
When the extension is not connected with APT, it is recognized as an SLT connection and the dummy communication is
established.
established.
Interface block diagram of CPU and ICM
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KX-TEA308RU
2) Data Communication of ASIC and PITS
When APT I/F Module in CPU send the request signal to the proprietary telephone and after receiving the key input information
(19 pulses) from the proprietary telephone and sending data (47 pulses) for LED control. APT I/F Module will receive
acknowledge signal from the proprietary telephone.
a) Reception
The data from the proprietary telephone is received via H and L lines along the path shown below.
H.L line
(19 pulses) from the proprietary telephone and sending data (47 pulses) for LED control. APT I/F Module will receive
acknowledge signal from the proprietary telephone.
a) Reception
The data from the proprietary telephone is received via H and L lines along the path shown below.
H.L line
→ C208 → IC200 →T201 → R235 → Q210 → CPU
b) Transmission
The data to the proprietary telephone is transmitted along the following Path.
CPU
The data to the proprietary telephone is transmitted along the following Path.
CPU
→ Q209 → Q215 → T201 → IC200 → C208 → H.L line
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KX-TEA308RU
11.7. CONTROL CIRCUIT
11.7.1. Composition
The control block is composed of the 16bit CPU(IC700: operating on 23.966MHz system clock from the 47.936MHz external crystal
oscillator), the 8Mbit Flash ROM, the 4Mbit SRAM, and the discrete logic IC (IC7, IC8) for the I/O Port to control the extension.
The port to control the CO, the clock IC, the address decoder, and other CPU Peripheral circuit are included in the IC700.Also, the
IC700 includes functions such as Extension CID(FSK, DTMF), MODEM sending/receiving, BGM, OGM recording/playing, DTMF
tone, CNG tone, CPT tone, and VOX detection.
the SRAM has a lithium battery as back up for protection of the memory of information of such as the speed dial, date, dial data,
and system data, etc. This battery is back up clock IC in IC700 too.
oscillator), the 8Mbit Flash ROM, the 4Mbit SRAM, and the discrete logic IC (IC7, IC8) for the I/O Port to control the extension.
The port to control the CO, the clock IC, the address decoder, and other CPU Peripheral circuit are included in the IC700.Also, the
IC700 includes functions such as Extension CID(FSK, DTMF), MODEM sending/receiving, BGM, OGM recording/playing, DTMF
tone, CNG tone, CPT tone, and VOX detection.
the SRAM has a lithium battery as back up for protection of the memory of information of such as the speed dial, date, dial data,
and system data, etc. This battery is back up clock IC in IC700 too.
11.8. TONE GENERATOR CIRCUIT
11.8.1. Composition
This system has three different tones, 620Hz, 440Hz, 350Hz.
ASIC make the 350Hz, 620Hz and 440Hz square wave signals.
The 350Hz and 440Hz square wave signals are shaped by the low pass filter to sine wave and become tone 1.
On the other hand, 620Hz, square wave signal is shaped by the low pass filter to sine wave and becomes tone 2.
Tone signals 1 and 2 turn ON and OFF at the cross point, thus dial tone, busy tone, and other tones, are produced.
ASIC make the 350Hz, 620Hz and 440Hz square wave signals.
The 350Hz and 440Hz square wave signals are shaped by the low pass filter to sine wave and become tone 1.
On the other hand, 620Hz, square wave signal is shaped by the low pass filter to sine wave and becomes tone 2.
Tone signals 1 and 2 turn ON and OFF at the cross point, thus dial tone, busy tone, and other tones, are produced.
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KX-TEA308RU
11.9. DTMF GENERATOR CIRCUIT
11.9.1. Composition
A DTMF tone is generated by the DSP in the CPU and sent to an CO line.
11.10. DTMF RECEIVER CIRCUIT
11.10.1. Composition
The DTMF receiver circuit is composes of four DTMF receivers.
IC606 and IC607 are used for the DTMF receivers from SLT connected to the extension.
The DTMF signal is the 4bit parallel data and read by CPU.
IC606 and IC607 are used for the DTMF receivers from SLT connected to the extension.
The DTMF signal is the 4bit parallel data and read by CPU.
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KX-TEA308RU
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