GL6851
GL6851
TWO TONE RINGER
Description
The GL6851 tone ringer is a monolithic device,
which incorporates two oscillators, an 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 GL6851 has provision for
adjustment of the supply initiation current.
Pin Configuration
VCC 1
RSL 2
8 OUTPUT
7 HIGHOSC_2
GL6851
LOWOSC_1 3
LOWOSC_2 4
6
5
HIGHOSC_1
GND
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.
Adjustable for reduced supply initiation current
Include ESD protection.
Block Diagram
4
3
2
1
POWER SUPPLY
CONTROL CIRCUIT
(WITH HYSTERESIS)
LOW FREQUENCY
OSCILLATOR
HIGH FREQUENCY
OSCILLATOR
OUTPUT
AMPLIFIER
5
6
7
8
-1-
GL6851
Absolute Maximum Ratings (Ta = 25℃)
CHARACTERISTICS
Supply Voltage
Power Dissipation
Operating Temperature
Storage Temperature
SYMBOL
V
CC
Po
Topr
Tstg
VALUE
30
400
-25 to 65
-65 to 150
UNIT
V
mW
℃
℃
Electrical Characteristics (Ta = 25℃)
CHARACTERISTICS
Operating Supply Voltage
Initiation Supply Voltage
1
Initiation Supply Current
1
Sustaining Voltage
2
Sustaining Current
2
Output Voltage High
Output Voltage Low
SYMBOL
V
CC
V
SI
I
SI
V
SUS
I
SUS
V
OH
V
OL
f
H1
High Frequency 1
High Frequency 2
Low Frequency
f
H2
f
L
R3=191K,C3=6800pF
R3=191K,C3=6800pF
R2=165K,C2=0.47µF
461
576
9.0
512
640
10
563
704
11.0
Hz
Hz
Hz
TEST CONDITION
MIN
-
17
0.9
9.7
0.4
17
-
TYP
-
19
2.0
11.0
1.0
19
-
MAX
29.0
21
3.7
12.0
2.0
21
2
UNIT
V
V
mA
V
mA
V
V
V
CC
=21V, I
8
=-10mA
Pin6=6V,Pin7=GND
V
CC
=21V, I
8
= 10mA
Pin6=GND,Pin7=6V
*
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.
-2-
GL6851
PIN DESCRIPTION
PIN NUMBER
PIN 1
PIN2
PIN3
PIN 4
PIN 5
PIN 6
PIN 7
PIN 8
PIN FUNCTION
VCC
RSL
LOWOSC_1
LOWOSC_2
GND
HIGHOSC_1
HIGHOSC_2
OUTPUT
DESCRIPTION
Operating supply D.C. voltage rectified
from ringing signal.
Initiation current programming Pin.
(Must be connected)
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
Ground
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
Tone output
APPLICATON CIRCUIT
TIP
C1
R1
C5
1
RSL
7K - 13K
D1
RING
C4
R1 = 560 ohm
R2 = 165 kohm
R3 = 191 kohm
R2
2
3
4
8
7
6
5
R3
C3
10K
VOLUME
GL 6851
C1 = 0.9uF
C2 = 0.47uF
C3 = 6.8nF
C4 = 22µf / 35V
C5 = 0.22 uF
D1 = 29 V
C2
15K
1300 : 8 ohm
-3-
