铃声芯片 IL2418N/D替代L1240

Telephone Tone Ringer withBridge Diode

The lL2418 is a monolithic integrated circuit telephone tone ringer withbridge diode, when coupled with an appropriate transducer, it replaces theelectro-mechanical bell. The device is designed for use with cither a piezotransducer or an inexpensive transformer coupled speaker to produce apleasing tone composed of a high frequency (fe) alternating with a lowfrequency (f)resulting in a warble frequency. The supply voltage isobtained from the AC ring signal and the circuit is designed so that noiseon the line or variation of the ringing signal can not afect correctoperation of the device.

• On chip high voltage full wave diode bridge rectifier

• Low current consumption, in order to allow the parallel operation ofthe 4 devices

• Low cxternal 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