Panasonic KX-T7453, Service Manual, Page: 12 / 57

RXD 22
TTL
input
PCM
interface
Input terminal for PCM data.
TXD 23 output Output terminal for PCM data
-FSYNC 24
TTL
input Input terminal of Sync. signal for PCM interface. The frequenc
of input sync.
signal is 8 kHz.
BCLK 25
Input terminal of shift clock pulse for PCM deta. Input pulse
frequency range is 64 kHz~2.048 kHz.
PCM data (TXD termianl signal) is output st the positive edge.
PCM data (RXD terminal signal) is sampled at the negative ed
The sameling is performed inside LSI.
MCLK 26 Output Clock
Clock pulse output terminal. Output pulse frequency is
6.144MHz.
System reset (inputting “0” to -RESET terminal) doesn’t stop
this output.
CLKO 27
Clock pulse output terminal which has selective frequencies.
The following 4 frequencies can be selected by resistor settin
12.228, 4.096, 2.048, 1.536 (MHz).
System reset (inputting “0” to -RESET terminal) selects the
frequency of 1.536MHz and doesn’t stop this output.
DG2 28 ---
Power
supply, etc.
Ground terminal of digital circuit.
OSCI 29 --- Clock
Input terminal of oscillation circuit.
Connect the oscillator and resistor berween this terminal and
pin 30 (OSCO), moreover, connect the capacitor between this
terminal and digital ground to make the oscillation circuit.
OSCO 30 ---
Output terminal of oscillation circuit.
Connect the oscillator and resistor berween this terminal and
pin 29 (OSCI), moreover, connect the capacitor between this
terminal and digital ground to make the oscillation circuit.
D5V2 31 ---
Power
supply, etc.
5V power supply terminal of digital circuit.
-INT 44 Output
Micro-
computer
interface
Outputs 8 kHz clock pulse which is synchronized with -FSYNC
TEST 45
CMOS
input Power
supply, etc. Test terminal
Connect to the digital ground.
A5V3 46 --- 5V power supply terminal of analog circuit.
HI 47
Analog
input
Analog
Input terminal of TX handset signal.
Either this signal or the signal supplied to pin 49 (HI) is input
AD converter.
VBB 48 ---
Power
supply, etc. Reference voltage terminal of AD converter.
Connect the capacitor of 10 F between VBB terminal and p
50 (AG3).
MI 49
Analog
input
Analog
Input terminal of TX microphone signal.
Either this signal or the signal supplied to pin 47 (HI) is input
AD converter.
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