GL6850
1
GL6850
TWO TONE RINGER
Description
The GL6850 tone ringer is a monolithic device,
which incorporates two oscillators, and output
amplifier and a power supply control circuit. The
oscillator frequencies can be adjusted over a wide
range by selection of external components. One
oscillator, normally operated at a low frequency,
causes the second oscillator to alternate between its
nominal frequency and a related higher frequency. The
resulting output is a distinct warbling tone. The output
amplifier will drive either a transformer coupled
loudspeaker or a piezo-ceramic transducer.
The device can be powered from a telephone line or
a fixed d.c. supply. The power control circuit has built-
in hysteresis to prevent false triggering and rotary dial
chirps. The GL6850 can be triggered externally under
logic control
.
Pin Configuration
Features
Low current consumption.
Designed for telephone bell replacement.
Small size MINIDIP package.
Adjustable 2- frequency tone.
Built-in hysteresis prevents false triggering and rotary dial CHIRPS.
Alarms or other alerting devices.
External triggering or ringer disable.
Include ESD protection.
Block Diagram
1
2
3
4
5
6
7
8
GL6850
VCC
TRIG_IN
LOWOSC_1
LOWOSC_2
OUTPUT
HIGHOSC_2
HIGHOSC_1
GND
5
6
7
8
4
3
2
1
POWER SUPPLY
CONTROL CIRCUIT
(WITH HYSTERSIS)
LOW FREQUENCY
OSCILLATOR
HIGH FREQUENCY
OSCILLATOR
OUTPUT
AMPLIFIER
GL6850
2
Absolute Maximum Ratings (Ta = 25
)
CHARACTERISTICS
SYMBOL
VALUE
UNIT
Supply Voltage
Power Dissipation
Operating Temperature
Storage Temperature
V
CC
Po
Topr
Tstg
30
400
-25 to 65
-65 to 150
V
mW
Electrical Characteristics (Ta = 25
)
CHARACTERISTICS
SYMBOL
TEST CONDITION
MIN
TYP
MAX UNIT
Operating Supply Voltage
V
CC
-
-
29.0
V
Initiation Supply Voltage
1
V
SI
17
19
21
V
Initiation Supply Current
1
I
SI
0.9
2.0
3.7
mA
Sustaining Voltage
2
V
SUS
9.7
11.0
12.0
V
Sustaining Current
2
I
SUS
0.4
1.0
2.0
mA
Trigger Voltage
3
V
TR
V
CC
= 15 V
9.5
-
-
V
Trigger Current
3
I
TR
V
CC
= 15 V
40
-
1000
5
A
Disable Voltage
4
V
DIS
V
CC
= 21 V
-
-
0.8
V
Disable Current
4
I
DIS
V
CC
= 21 V
-50
-
-
A
Output Voltage High
V
OH
V
CC
=21V, I
8
=-10mA
Pin6 =6V,Pin7=GND
17
19
21
V
Output Voltage Low
V
OL
V
CC
=21V, I
8
= -10mA
Pin6= GND,Pin7=6V
-
-
2
V
High Frequency 1
High Frequency 2
Low Frequency
f
H1
f
H2
f
L
R3=191K, C3=6800Pf
R3=191K, C3=6800pF
R2=165K, C2=0.47F
461
576
9.0
461
640
10
563
704
11.0
Hz
Hz
Hz
* NOTE
1. Initial supply voltage (V
SI
) is the supply voltage required to start the tone ringer oscillation.
2. Sustaining voltage (V
SUS
) in the supply voltage required to maintain oscillation.
3. V
TR
and I
TR
are the conditions applied to trigger to start for V
SUS
V
CC
V
SI
4. V
DIS
and I
DIS
are the conditions applied to trigger to inhibit oscillation for V
SI
V
CC
5. Trigger current must be limited to this value externally.
GL6850
3
PIN DESCRIPTION
PIN NUMBER
PIN FUNCTION
DESCRIPTION
PIN 1
VCC
Operating supply D.C. voltage rectified from ringing signal.
PIN2
TRIG_IN
Oscillator External Trigger/Inhibit pin (must beconnected through
a current limiting resistor, which is used to program the slope of
supply current vs voltage.)
PIN3
LOWOSC_1
PIN 4
LOWOSC_2
Low Frequency Time Constant Adjustment pins f
L
is controlled
externally by R
2
and C
2
f
L
= 1/1.289R
2
C
2
PIN 5
GND
Ground
PIN 6
HIGHOSC_1
PIN 7
HIGHOSC_2
High Frequency Time Constant Adjustment Pins f
H1
and f
H2
are
controlled externally by R
3
and C
3
.
f
H1
=1/1.504R
3
C
3
, f
H2
= 1/1.203R
3
C
3
PIN 8
OUTPUT
Tone output
APPLICATON CIRCUIT
100K-200K
1300 : 8 ohm
TIP
C1 R1
RING
C4
D1
R2
C2
C5
R3
C3
15K
10K
VOLUME
C1 = 0.9uF
C2 = 0.47uF
C3 = 6.8nF
C4 = 22uF / 35V
C5 = 0.22uF
D1 = 29 V ZD
R1 = 560 ohm
R2 = 165 kohm
R3 = 191 kohm
1
2
3
4
5
6
7
8
GL 6850
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