GL6840
GL6840A
Electronic Two Tone Ringer
Description
GL6840A are monolithic integrated circuits designed
to replace the mechanical bell in telephone sets,
in connection with an electro acoustical converter.
The device can drive either directly a piezo ceramic
converter(buzzer) or a small loudspeaker. In this
case a transformer is needed. The two tone frequen-
cies generated are switched by an internal oscillator
in a fast sequence and made audible across output
amplifiers in the transducer, both tone frequencies
and switching frequency can be externally adjusted.
The supply voltage is obtained from the AC rings
signal and the circuit is designed so that noise on the
line or variations on the ringing signal cannot affect
the correct operation of the devices.
The output bridge configuration allows to use a high
impedance transducer with acoustical results much
better than in a single ended configuration. The two
outputs can also be connected independently to
different converters or actuators(acoustical, opto and
logic)
Pin Configuration
Line
GND
Sweep rate
control capacitor
Output freq.
Control resistor
1
GL6840A
2
3
4
8
7
6
5
Line
Rectifier
capacitor
Buzzer
Buzzer
(Top View)
Absolute Maximum Ratings
Calling Voltage(f=50§
Ô
)
continuous
Calling Voltage(f=50§
Ô
)
5s ON/10s OFF
Supply Current
Operating Temperature
Storage Temperature
120Vrms
200Vrms
22§
Ì
-20 to 75¡
É
-65 to 150¡
É
14 - R
1
(§
Ú
)
95
Features
Test Circuit
• Low current consumption, in order to allow the
1000
f
2
= 0.717 x f
1
f
sweep
=
parallel operation of 4 devices
C
1
(§
Ý
)
• Integrated rectifier bridge with zener diodes to
1§
Þ
2.2§
Ú
protect against overvoltages
Buzzer
• Little external circuitry
• Tone and switching frequencies adjustable by V
AB
Line
8
5
external components
GL6840A
7
6
£ «
• Integrated voltage and current hysteresis
1
2
3
4
10§
Þ
• Bridge output configuration
V
S
C
1
R
1
14§
Ú
100§
Ý
3.26 x 10
4
f
1
=
x (2 - e
For GL6840A
R
1
(§
Ú
)
)
1
HYNIX [ HYNIX SEMICONDUCTOR ]
