M-991
Call Progress Tone Generator
Features
Generates standard call progress tones
Digital input control
Linear (analog) output
Power output capable of driving standard line
14-pin DIP and 16-pin SOIC package types
Single supply 5V CMOS (low power)
Inexpensive 3.58 MHz time base
Temperature range from -25ºC to 70ºC (-01 ver-
sion)
•
Temperature range from -40ºC to 85ºC (-02 ver-
sion)
•
•
•
•
•
•
•
•
Applications
•
•
•
•
•
Telephone systems
Test equipment
Callback
Security systems
Billing systems
Description
The M-991 is a call progress tone generator integrated
circuit for use in telephone systems. The circuit uses
low-power CMOS techniques to generate tones which
are digitally controlled and highly linear. The M-991 is
designed to permit operation with almost any system.
The use of integrated circuit techniques allows the M-
991 to incorporate the control, tone generating, and
power output buffer into a single 14-pin DIP or a 16-pin
SOIC. A 3.58-MHz (color burst) crystal-controlled time
base guarantees accuracy and repeatability.
Ordering Information
Part #
M-991
M-991-01SM
M-991-01SMTR
M-991-02SM
M-991-02SMTR
Description
14-pin plastic DIP
16-pin SOIC
16-pin SOIC Tape and Reel
16-pin SOIC, Extended
Temperature Range
16-pin SOIC, Extended
Temperature Range, Tape and
Reel
Pin Assignments
Block Diagram
DS-M991-R1
www.clare.com
1
M-991
Absolute Maximum Ratings
Storage Temperature
Operating Ambient Temperature
Operating Ambient Temperature
for the M-991-02SM
V
DD
Any Input Voltage
-55° to 125° C
-25° to 70° C
-40° to 85° C
7.0V
V
SS
-0.6 to V
DD
+0.6V
Absolute Maximum Ratings are stress ratings. Stresses in
excess of these ratings can cause permanent damage to
the device. Functional operation of the device at these or
any other conditions beyond those indicated in the opera-
tional sections of this data sheet is not implied. Exposure of
the device to the absolute maximum ratings for an extend-
ed period may degrade the device and effect its reliability.
Note:
1. Exceeding these ratings may permanently damage the M-991.
Specifications
Parameter
Power Supply
and Reference
V
DD
Current Drain, IDD
V
REF
Pin:
Deviation from (V
DD
+ V
SS
)/2
Internal Resistance from V
REF
to V
DD
, V
SS
Oscillator
Frequency Deviation
External Clock: (XOUT open)
V
IL
V
IH
Duty Cycle
XIN, XOUT Loading:
Capacitance
Resistance
Tone Output
Frequency Deviation
Level
Distorting Components
Idle
OUTDRIVE Envelope Rise Time
Control
DX, CE Pns:
V
IL
V
IH
Mute Pins:
VOL (I
SINK
= -100 µA)
Timing
V
OH
(I
SOURCE
= 100 µA)
Data Setup (t
DS
)
Data Hold (t
DH
)
Chip Enable Fall (t
PL
)
Tone On Delay (t
TO
)
Tone Off Delay (t
TD
)
Mute Delay from Outdrive (t
MO
)
Notes:
(unless otherwise specified)
1. All DC voltages are referenced to V
SS
.
2. Vrms per tone, 540 W load.
3. Any one frequency relative to the lowest level output tone (f<4000 Hz).
4. 0 dBm = 0.775 Vrms.
5. To 90% maximum amplitude.
6. For all supply voltages in the operating range.
Min
4.75
-
-2
3.25
-0.01
0
V
DD
- 0.2
40
-
20
-0.5
100
-35
-
-
-
2.5
-
V
DD
- 1.5
200
10
-
-
-
-
Typ
-
2.0/4.0
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Max
5.25
-
+2
6.75
+0.01
0.2
V
DD
60
10
-
+0.5
180
-
-60
4
0.5
-
1.5
-
-
-
90
5
5
200
Units
V
mA
%
kΩ
%
V
V
%
pF
MΩ
%
mV
dB
dBm
ms
V
V
V
V
ns
ns
ns
ms
ms
ns
Notes
1
8
7
10
-
-
2
3
4
5
6
11
7. At XOUT pin as compared to 3.579545 MHz.
8. OUTDRIVE with load >5 KW/OUTDRIVE with
540 W load.
9. Resistance at V
REF
to V
DD
or V
SS
> 1 MW.
10. Crystal oscillator active.
11. Measured 90% to 10%.
2
www.clare.com
Rev. 1
M-991
Call Progress Tone Generation
Call progress tones are audible tones sent from
switching systems to calling parties (or equipment) to
indicate the status of calls. Calling parties can identify
the success of a placed call by what is heard after dial-
ing. The M-991 series utilizes a highly linear tone gen-
erator that produces the unique frequencies (singly or
in pairs) that are common to call progress signals.
Duration and frequency selection are digitally con-
trolled (see the Data/Tone Selection table below for
data settings for a particular tone output). A typical
control sequence for the M-991 is: (1) set data lines to
desired frequency selection, (2) wait for data lines to
settle, (3) drive the chip enable (CE) low, (4) maintain
CE low for desired tone duration (Note: data lines may
be changed after data hold time), and (4) return CE to
Data/Tone Selection
D0
0
0
0
0
0
0
0
0
1
1
D1
0
0
0
0
1
1
1
1
0
0
D2
0
0
1
1
0
0
1
1
0
0
D3
0
1
0
1
0
1
0
1
0
1
Frequency (Hz)
1
2
350
440
400
off
440
off
440
480
440
620
480
off
480
620
350
off
620
off
941
1209
Use
Dial Tone
Special
Alert Tone
Audible Ring
Pre-empt
Bell high tone
Reorder(Bell low)
Special
Special
DTMF “
*
”
a logic high. (Commonly used call progress tones are
shown in the Data/Tone Selection table below.) In a
bus-oriented system, noise on the data lines may
propagate through the device and appear at the out-
put. To safeguard against this, use an external latch to
lock the data into the device. In addition, it is good
practice to bypass the V
REF
pin to ground with a small
capacitor (0.01 mF) to reduce power supply noise. The
designer should be aware of device timing require-
ments and design accordingly. The data input pins
may be tied high (+5 VDC) or low (ground) as required,
but D4 and D5 must be left open. Beware of hardwiring
the CE pin for dedicated tone generation. This input is
edge triggered. An RC network like that shown in the
Power-on Reset Circuit on Page 4 should be used to
momentarily reset the device immediately following
power-up to ensure proper operation.
Pin Function
Pin
CE
D0 - D3
D4-D5
MUTE
OUTDRIVE
V
DD
V
REF
V
SS
X
IN
X
OUT
Function
Latches data and enables output (active
low input).
Data input pins. (See Data/Tone Selection.)
Leave open.
Output indicates that a signal is being generated at
OUTDRIVE.
Linear buffered tone output.
Most positive power supply input pin.
Internally generated mid-power supply voltage
(output).
Most negative power supply input pin.
Crystal oscillator or digital clock input.
Crystal oscillator output.
Standard Call Progress Tones
Tone Name
Dial
Reorder
Busy
Audible Ring
Recall Dial
Special AR
Intercept
Call Waiting
Busy Verification
Executive Override
Confirmation
Rev. 1
Frequency (Hz)
1
2
350
480
480
440
350
440
440
440
440
440
350
440
620
620
480
440
480
620
Off
Off
Off
440
Steady
Interruption Rate
Repeat, tones on and off 250 ms ± 25 ms each.
Repeat, tones on and off 500 ms ± 50 ms each.
Reat, tones on 2 ± 0.2 s, tones off 4 ± 0.4 s
Three bursts tones on and off 100 ms ± 20 ms each followed by dial tone.
Tones on 1 ± 0.2s, followed by single 440 Hz on for 0.2s on, and silence for 3 ±
0.3 s, repeat.
Repeat alternating tones, each on for 230 ms ± 70 ms with total cycle of 500 ±
50 ms.
One burst 200 ± 100 ms
One burst of tone on 1.75 ± 0.25 s before attendant intrudes, followed by burst
of tone 0.65 ± 0.15 s on, 8 to 20 s apart for as long as the call lasts
One burst of tone for 3 ± 1 s before overriding station intrudes
Three bursts on and off 100 ms each or 100 ms on, 100 ms off, 300 ms on
www.clare.com
3
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
