ml7005mb Oki Semiconductor, ml7005mb Datasheet - Page 19

• Manufacturer Part Number: ml7005mb
• Description: Dtmf Transceiver Ml7005dtmf Transceiver
• Manufacturer: Oki Semiconductor

IN
¡ Semiconductor
FUNCTIONAL DESCRIPTION
Oscillation Circuit
The X1 and X2 should be connected by a 3.579545 MHz crystal.
When the load capacitance of the crystal is 16pF, X1 and GND should be connected by a 20 pF
capacitor, and X2 and GND also should be connected by a 20 pF capacitor.
If necessary, an external clock should be input to X1 via a 1000 pF capacitor, and X2 should be
left open.
DTMF Receiver, CPT Detector Input Level Adjustment
Adjust the input level according to the method shown in the figure 8.
Determine the value of a usable resistor so that the levels of the outputs (DTIO, CPDIO) of each
amplifier at a maximum input level are less than the maximum detect level described in the AC
Characteristics.
CA
R
Figure 6 Crystal Connection
A
3.579545MHz
R
B
, R
CA ≥ 0.1 mF
R
A
C
≥ 100 kW
≥ 50 kW
R
DTRIM
DTRIP
DTRIO
C
R
B
SG
C1
C2
(CPDIM)
Gain = 1 +
(CPDIP)
(CPDIO)
Figure 8 DTMF, CPT Input Level Adjustment
X1
X2
+
–
R
R
B
C
£ 10
3.579545MHz
Figure 7 External Clock Connection
IN
CA
R
D
DTRIM
DTRIO
DTRIP
R
E
SG
(CPDIM)
(CPDIO)
(CPDIP)
Gain =
–
+
R
R
D
E
X1
X2
£ 10
ML7005
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