KA2418B Datasheet, PDF (1/3 Pages) Samsung semiconductor – TONE RINGER WITH BRIDGE DIODE

KA2418B/28
TONE RINGER WITH BRIDGE DIODE
INTRODUCTION
The KA2418B/28 is a monolithic integrated circuit telephone tone
ringer with bridge diode, when coupled with an appropriate
transducer, it replaces the electromechanical bell. This 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 frequencys (fH1, fH2) alternating with a low frequency (fS)
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.
8-DIP-300
FEATURES
• Built-in full wave bridge diode rectifier
• Low current consumption, in order to allow the
parallel operation of the 4 devices
• Few external components
• Tone and adjustable switching frequencies by
external components
• High noise immunity due to built-in voltage to
current hysteresis
• Adjustable activation voltage
• Internal zener diodes to protect against over
voltages
• Adjustable ringer impedance with external
components.
BLOCK DIAGRAM
ORDERING INFORMATION
Device
Package Operating Temperature
KA2418B
KA2428
8-DIP-300
- 20°C ~ + 70°C
APPLICATIONS
• Electronic telephone ringers
• Extension ringers
RECTIFIER
CAPACITOR
7
ACTIVATION
VOLTAGE ADJUSTABLE
6
TIP ⁸
-
RING ¹
+
POWER
SUPPLY
CONTROL
CIRCUIT
LOW
FREQ OSC
HIGH
FREQ OSC
OUTPUT
AMP
5
OUTPUT
2
GND
3
SWEEP RATE
CONTROL
CAPACITOR
4
OUTPUT FREQUENCY
CONTROL RESISTOR
Fig. 1