UNISONIC TECHNOLOGIES CO., LTD
31002A
TELEPHONE TONE RINGER
DESCRIPTION
The UTC
31002A
is a bipolar integrated circuit designed for
telephone bell replacement. It can also be used as alarms or other
alerting devices.
LINEAR INTEGRATED CIRCUIT
SOP-8
FEATURES
*Designed for telephone bell replacement.
*Low current drain for multiple extension of lines.
*Adjustable 2-frequency tone.
*Adjustable warbling rate.
*Built-in hysteresis prevents false triggering and rotary dial
'CHIRPS'.
*Programmable for initiation current by simple external resistor
DIP-8
*Pb-free plating product number: 31002AL
ORDERING INFORMATION
Ordering Number
Normal
Lead Free Plating
31002A-D08-T
31002AL-D08-T
31002A-S08-R
31002AL-S08-R
31002A-S08-T
31002AL-S08-T
Package
DIP-8
SOP-8
SOP-8
Packing
Tube
Tape Reel
Tube
www.unisonic.com.tw
Copyright © 2008 Unisonic Technologies Co., Ltd
1 of 6
QW-R108-005.C
31002A
ABSOLUTE MAXIMUM RATINGS
(Ta=25°C)
PARAMETER
LINEAR INTEGRATED CIRCUIT
SYMBOL
RATINGS
UNIT
Supply Voltage
V
CC
30
V
DIP-8
P
D
800
mW
Power Dissipation
400
mW
SOP-8
P
D
Operating Temperature
T
OPR
-45 ~ +85
°C
Storage Temperature
T
STG
-65 ~ +150
°C
Note: Absolute maximum ratings are those values beyond which the device could be permanently damaged.
Absolute maximum ratings are stress ratings only and functional device operation is not implied.
ELECTRICAL CHARACTERISTICS
(Ta=25°C, all voltage referenced to GND unless otherwise specified)
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
Operating Supply Voltage
Vcc
29.0
Initiation Supply Voltage (Note 1)
Vsi
See Fig.2
17
19
21
Initiation Supply Current (Note 1)
6.8K-Pin 2 to GND
1.3
2.8
4.2
Sustaining Voltage (Note 2)
Vsus
See Fig.2
9.7
11.0
12.0
Sustaining Current (Note 2)
Isus
No Load Vcc=Vsus, See Fig.2
0.7
1.4
2.5
Vcc=21V, I8=-15mA
17.0
19.0
21.0
Output Voltage High
V
OH
Pin6=6V, Pin7=GND
Vcc=21V, I8=15mA
1.6
Output Voltage Low
V
OL
Pin6=GND, Pin7=6V
500
Pin3=6V, Pin4=GND
IIN(Pin 3)
500
Pin7=6V, Pin6=GND
IIN(Pin 7)
High Frequency 1
FH1
R3=191K, C3=6800pF
461
512
563
High Frequency 2
FH2
R3=191K, C3=6800pF
576
640
704
Low Frequency
FL
R2=165K, C2=0.47μF
9.0
10
11.0
NOTE (See electrical characteristics sheet)
1. Initiation supply voltage (Vsi) is the supply voltage required to start the tone ringer oscillating.
2. Sustaining voltage (Vsus) is the supply voltage required to maintain oscillation.
UNIT
V
V
mA
V
mA
V
V
nA
nA
Hz
Hz
Hz
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
4 of 6
QW-R108-005.C
31002A
APPLICATION NOTE
LINEAR INTEGRATED CIRCUIT
The application circuit illustrates the use of the UTC
31002A
device in typical telephone tone ringer application.
The AC ringer signal voltage appears across the TIP and RING inputs of the circuit and is attenua-ted by capacitor
C1 and resistor R1.
C1 also provides isolation from DC voltage (48V) on the exchanged line.
After full wave rectification by the bridge diode, the wave form is filtered by capacitor C4 to provide a DC supply for
the tone ringer chip.
As this voltage exceeds the initiation voltage (Vsi), oscillation starts.
With the components shown, the output frequency chops between 512Hz (F
H1
) and 640 Hz (F
H2
) at a 10 Hz (F
L
)
rate.
The loudspeaker load is coupled through a 1300Ω to 8Ω transformer.
The output coupling capacitor C5 is required with transformer coupled loads.
When driving a pizeo-ceramic transducer type load, the coupling C5 and transformer (1300Ω:8Ω) are not required.
However, a current limiting resistor is required.
The low frequency oscillator oscillates at a rate (F
L
) controlled by an external resistor (R2) and capacitor (C2).
The frequency can be determined using the relation F
L
=1/1.289 R2* C2. The high frequency oscillates at a F
H1
,
F
H2
controlled by an external resistor (R3) and capacitor (C3). The frequency can be determined using the relation
F
H1
=1/1.504 R3*C3 and F
H2
=1/1.203 R3*C3
Pin 2 of the UTC
31002A
allows connection of external resistor RSL, which is used to program the slope of the
supply current vs. supply voltage characteristics (see Fig.3), and hence the supply current up to the initiation voltage
(Vsi). This initiation voltage remains constant independent of RSL.
The supply current drawn prior to triggering varies inversely with RSL, decreasing for increasing value of
resistance. Thus, increasing the value of RSL, will decrease the amount of AC ringing current required to trigger the
device. As such, longer sucribser loops are possible since less voltage is dropped per unit length of loop wire due to
the lower current level. RSL can also be used to compensated for smaller AC coupling capacitors (C5 on Fig.4)
(higher impedance) to the line which can be used to alter the ringer equivalence number of a tone ringer circuit.
The graph in Fig.3 illustrates the variation of supply current with supply voltage of the UTC
31002A.
Three curves are drawn to show the variation of initiation current with RSL. Curve B ( RSL=6.8K) shows the I-V
characteristic for UTC
31002A
tone ringer. Curve A is a plot with RSL<6.8KΩ and shows an increase in the current
drawn up to the initiation voltage Vsi. The I-V characteristic after initiation remains unchanged. Curve C illustrates
the effect of increasing RSL above 6.8K initiation current decreases but again current alter triggering is unchanged.
Icc(mA),Supply Current
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
Supply Current (mA)
5 of 6
QW-R108-005.C
Electronics Design Contest
京公网安备 11010802033920号
EEWORLD
