SL2418
Telephone Tone Ringer with Bridge Diode
The SL2418 is a monolithic integrated circuit telephone tone ringer
with bridge diode, when coupled with an appropriate transducer, it
replaces the electro-mechanical bell. The device is designed for use
with either a piezo transducer or an inexpensive transformer coupled
speaker to produce a pleasing tone composed of a high frequency (fR)
alternating with a low frequency (fL) resulting in a warble frequency.
The supply voltage is obtained from the AC ring signal and the circuit
is designed so that noise on the line or variation of the ringing signal
can not affect correct operation of the device.
• On chip high voltage full wave diode bridge rectifier
• Low current consumption, in order to allow the parallel operation
of the 4 devices
• Low external component count
• Tone and switching frequencies adjustable by external
components
• High noise immunity due to built-in voltage-current hysteresis
• Activation voltage adjustable
• Internal zener diodes to protect against over voltages
• Ringer impedance adjustable with external components
ORDERING INFORMATION
SL2418N Plastic
SL2418D SOIC
TA = -20° to 70° C
for package
PIN ASSIGNMENT
BLOCK DIAGRAM
SLS
System Logic
Semiconductor