OKI MSM6234

E2A0022-16-X0
¡ Semiconductor
MSM6234
¡ Semiconductor
This version: Jan.
1998
MSM6234
Previous version: Nov. 1996
DTMF Tone Dialer LSI
GENERAL DESCRIPTION
The MSM6234 is a tone dialer LSI which is fabricated by Oki's low power consumption CMOS silicon
gate technology.
The MSM6234 can generate 16 DTMF (Dual Tone Multi Frequency) signals which consists of 4 higher
group frequencies and 4 lower group frequencies.
FEATURES
• The standard 2 of 8 keyboard can be used.
• The low power consumption by use of CMOS silicon gate technology.
• Supply voltage 2.5 V to 8.5 V.
• Either single tone or dual tone output.
• 3.579545 MHz crystal oscillation.
• Interface with microcotroller.
• Package:
16-pin plastic DIP
(DIP16-P-300-2.54)
(Product name : MSM6234RS)
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¡ Semiconductor
MSM6234
BLOCK DIAGRAM
3.579545 MHz
OSC I
OSC
OSC O
V DD
PR
R1
R2
R3
KEY BOARD
LOGIC
(ROW)
AKD
MUTE
LOGIC
1/2
CK
[LOW]
PROGRAMMABLE
DIVIDER
160, 146, 132, 118
16f L CK
8 STAGE
COUNTER
LADDER
NETWORK
R
R4
SINGLE
TONE
INHIBIT
V DD
V DD
INHIBIT
LOGIC
V DD
C1
C2
C3
VREF
ADDER
TONE
OUT
R
KEY BOARD
LOGIC
(COLUMN)
CK PROGRAMMABLE
PR
DIVIDER
92, 84, 76, 68
16f H CK
8 STAGE
COUNTER
LADDER
NETWORK
C4
V DD
V SS
[HIGH]
V DD
TONE
DISABLE
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¡ Semiconductor
MSM6234
PIN CONFIGURATION (TOP VIEW)
16 TONE OUT
VDD 1
15 SINGLE TONE
INHIBIT
TONE 2
DISABLE
C1 3
14 R1
C2 4
13 R2
C3 5
12 R3
VSS 6
11 R4
OSC1 7
10 AKD
OSC0 8
9 C4
16-Pin Plastic DIP
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¡ Semiconductor
MSM6234
PIN AND FUNCTIONAL DESCRIPTIONS
OSCI, OSCO
The 3.579545 MHz crystal oscillator is connected to these pins.
A feedback resistor and the condensers are incorporated.
OSC I
C
Crystal
3.579545
MHz
RFB
OSC O
C
MSM6234RS
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¡ Semiconductor
MSM6234
R1, R2, R3, R4, C1, C2, C3, C4
These are input pins of negative logic to be connected to the keyboard.
The standard 2 of 8 keyboard can be used with MSM6234RS as illustrated below.
R
1
2
3
A
4
5
6
B
7
8
9
C
*
0
#
D
V DD
R1
R
R2
R
R3
R
R4
R
R = 20 kW to 150 kW
C4
R
C3
ROW
R
C2
COL
R
C1
V SS
MSM6234RS
2 of 8 keyboard
R1 to R4 are the input pins of the row side, while C1 to C4 are the input pins of the column side. All
the pins are provided with the pull-up resistor of 20 kW to 150 kW internally.
The dual tone is output from the TONE OUT pin, by setting both of a row input and a column input
to the ground voltage.
The Table 1 (See Note) shows the relation between the nominal frequency and the tone output
frequency, while the Table 2 (See Note) shows the input condition of R1 to R4 pins and C1 to C4 pins.
• Refer to the Table 1 and Table 2
Table-1
Nominal
Frequency
Tone Output
Frequency
Accuracy (%)
R1
697 Hz
699.1 Hz
+0.30%
R2
770 Hz
766.2 Hz
–0.49%
R3
852 Hz
847.4 Hz
–0.54%
Effective Input
(ROW)
(COLUMN)
R4
941 Hz
948.0 Hz
+0.74%
C1
1209 Hz
1215.9 Hz
+0.57%
C2
1336 Hz
1331.7 Hz
–0.32%
C3
1477 Hz
1471.9 Hz
–0.35%
C4
1633 Hz
1645.0 Hz
+0.73%
Remarks
Low Group
High Group
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¡ Semiconductor
MSM6234
Table-2
Row Input
Column Input
Tone Output *
No
No
0V
1
1
fL + fH
No
1
fH
1
No
0V
More than 2
No
0V
More than 2
1
fH
No
More than 2
0V
1
More than 2
fL
More than 2
More than 2
0V
Remarks
Dual tone
Single tone
(Only column)
Single tone
Single tone
fL: Low Group
fH: High Group
* : The tone output shown is in the case when the load resistance is connected between the TONE
OUT pin and the VSS.
Sample Interface Circuit with Microcontroller
V DD
MSM4049
R1
R1
R2
R2
R3
R3
R4
R4
C1
C1
C2
C2
C3
C3
C4
TONE
OUT
1
6
8
C4
D
tt
V SS
t id
t t ≥ 50 ms and 30 ms £ tid £ 3 s
Figure 1
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¡ Semiconductor
MSM6234
AKD
The AKD pin drives the external bipolar transistor by its N-channel open drain output.
This pin is open when the key input is off, while it becomes low when the key input is on. AKD is
used for the mute of the transmitter/receiver.
Key input
OFF
ON
OFF
AKD
Open
"L"
Open
AKD
MSM6234RS
TONE DISABLE
This is an input pin to control the output of the TONE OUT pin.
When the input to this pin is high level, the TONE OUT pin normally operates. When the input to
this pin is low level, however, the output from the TONE OUT pin is prohibited even if the key input
is on.
AKD is effective at that time. This pin is provided with the pull-up resistance of 50 kW to 200 kW
internally.
key input
TONE DISABLE
AKD
TONE OUT
ON
OFF
"L"
"H"
Open
"L"
OFF
"L"
Open
"L"
V DD
50 kW to 200 kW
TONE DISABLE
MSM6234RS
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¡ Semiconductor
MSM6234
SINGLE TONE INHIBIT
When more than two columns are selected against only one row, or when more than 2 rows are
selected against only one column, the single tone is output from the TONE OUT pin.
This SINGLE TONE INHIBIT pin is a negative logic input pin to control the output of the TONE OUT
pin in those cases. Refer to the Table-2.
When the input to this pin is high level, both of the single tone and dual tone are output from the
TONE OUT pin. When the input to this pin is low level, however, the single tone is prohibited to
output from the TONE OUT pin and becomes DC level.
This pin is provided with the pull-up resistor of 50 kW to 200 kW.
V DD
50 kW to 200 kW
Pull up resistor
SINGLE TONE INHIBIT
MSM6234RS
TONE OUT
The low group frequency and the high group frequency selected by the keyboard are synthesized
and output from this TONE OUT pin. Because the output form is the NPN open emitter style, the
load resistance must be connected externally. It is same for the case of the single tone output. The
output amplitude of the high group is bigger than that of the low group by 1 to 2 dB.
The distortion of the dual tone is maximum 10%.
V DD
TONE OUT
MSM6234RS
R
V SS
VDD, VSS
VDD is a power supply.
VSS is ground.
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¡ Semiconductor
MSM6234
Sample Output Waveform of the Single Tone
V DD
1.0
13
0.9
14
15 15 15
12
0.8
13
12
11
0.7
14
11
10
10
9
0.6
9
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
8
8
7
7
0.4
6
6
0.3
5
5
0.2
4
4
3
3
0.1
2
2
1 1 1
(VREF)
Time
0.5
Figure 2
TONE AMPLITUDE (mV rms)
Tone Amplitude (mV rms)
900
800
700
600
500
R L = 1 kW
ROW TONE
400
300
3
4
5
6
7
V DD Æ V
8
9
Figure 3
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¡ Semiconductor
MSM6234
ABSOLUTE MAXIMUM RATINGS
Parameter
Symbol
Condition
Power Supply Voltage
VDD
Ta = 25°C
–0.3 to 9.5
V
Storage Temperature
TSTG
—
–55 to +150
°C
PD
Ta = 25°C
500
mW
Input Voltage
VI
—
VSS – 0.3 to VDD + 0.3
V
Output Voltage
VO
—
VSS – 0.3 to VDD + 0.3
V
Power Dissipation
Rating
Unit
RECOMMENDED OPERATING CONDITIONS
Symbol
Condition
Min.
Typ.
Max.
Unit
Power Supply Voltage
Parameter
VDD
—
2.5
5
8.5
V
Operating Temperature
Top
—
–30
—
+70
°C
Crystal Frequency
f(XT)
Ta = –30°C to +70°C
VDD = 2.5 V to 8.5 V
—
3.579545
—
MHz
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¡ Semiconductor
MSM6234
ELECTRICAL CHARACTERISTICS
DC Characteristics
Parameter
Input High Voltage
(Ta = –30°C to +70°C)
VIH
Condition
—
0.7VDD
—
VDD
Input Low Voltage
VIL
—
VSS
—
0.3VDD
Low Level Input
Leakage Current
IIL
VDD = 8.5 V, VIL = 0 V
–0.0567
—
–0.425
235
—
437
mV
rms
TONE OUT
Symbol
Min.
Typ.
Max.
Unit Applicable Pin
V C1 to C4, R1 to R4
V
C1 to C4, R1 to R4
mA C1 to C4, R1 to R4
"TONE OUT" Output Voltage
VOUT VDD = 3.0 V, RL = 1 kW
Difference of High/Low
Band Level
dB CR
VDD = 3.0 V to 8.5 V
1
1.5
2
dB
TONE OUT
Distortion
% DIS
VDD = 3.0 V to 8.5 V
—
—
10
%
TONE OUT
High Level Input Leakage
Current
Low Level Input
Leakage Current
IIH
VDD = 8.5 V, VIH = 8.5 V
—
—
1
mA
C1 to C4, R1 to R4
STI, TOND*
IIL
VDD = 8.5 V, VIL = 0 V
–42.5
—
–170
mA
STI, TOND*
Input High Voltage
VIH
—
0.7VDD
—
VDD
V
STI, TOND*
Input Low Voltage
VIL
—
0.3VDD
V
STI, TOND*
IDDS
—
VDD = 8.5 V,
No load, Key-OFF
VSS
Power Supply Current
(Stand-by)
—
—
200
mA
Power Supply Current
(Operating)
IDD
VDD = 8.5 V,
RL = 1 kW,
No load, Key-ON
—
—
25
mA
Low Level Output Leakage
Current
IOL
VDD = 3 V, VOL = 0.5 V
VDD = 8.5 V, VOL = 0.5 V
0.53
2.0
1.3
5.3
—
—
mA
AKD
"OFF" Leakage Current
IOFF
VDD = 8.5 V
—
—
10
mA
AKD
TONE OUT
Rise Time
trise
VDD = 3.0 V to 8.5 V
—
3.0
5.0
ms
TONE OUT
*: STI Æ SINGLE TONE INHIBIT
TOND Æ TONE DISABLE
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¡ Semiconductor
MSM6234
PACKAGE DIMENSIONS
(Unit : mm)
DIP16-P-300-2.54
Package material
Lead frame material
Pin treatment
Solder plate thickness
Package weight (g)
Epoxy resin
42 alloy
Solder plating
5 mm or more
0.99 TYP.
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