KA2418B/28 TONE RINGER WITH BRIDGE DIODE INTRODUCTION 8-DIP-300 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. 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. ORDERING INFORMATION Device KA2418B Package Operating Temperature 8-DIP-300 - 20°C ~ + 70°C KA2428 APPLICATIONS • Electronic telephone ringers • Extension ringers BLOCK DIAGRAM RECTIFIER CAPACITOR ACTIVATION VOLTAGE ADJUSTABLE 7 TIP 8 - RING 6 + POWER SUPPLY CONTROL CIRCUIT LOW FREQ OSC HIGH FREQ OSC 1 2 3 GND SWEEP RATE CONTROL CAPACITOR Fig. 1 4 OUTPUT FREQUENCY CONTROL RESISTOR OUTPUT AMP 5 OUTPUT KA2418B/28 TONE RINGER WITH BRIDGE DIODE ABSOLUTE MAXIMUM RATINGS Characteristic Symbol Value Unit VC 120 Vrms VC(0N-OFF) 200 Vrms ICC 22 mA T ORR -20 ~ +70 °C T STG -65 ~ +150 °C Calling Voltage (f = 50HZ) Continuous Calling Voltage (f = 50HZ) 5 Sec ON/10 Sec OFF Supply Current Operating Temperature Storage and Junction Temperature Absolute maximum ratings are those values beyond which permanent damage to the device may occur. These are stress ratings only and functional operation of the device at or beyond them is not implied. Long exposure to these conditions may affect device reliability. DC ELECTRICAL CHARACTERISTICS Characteristic (T a = 25°C) Symbol Test Conditions Min Operating Voltage VCC - - Typ - Max 26 Unit V Current Consumption without Lode ICC VS = 8.8 to 26V - 1.5 1.8 mA Activiation Voltage VON - 12.2 - 13 V Activiation Voltage Range VONR RA = 1KΩ 8 - 10 V Sustaining Voltage VSUS - 8 - 8.8 V Differential Resistance in off Condition RD(OFF) - 6.4 - - KΩ Output Voltage Swing V0(P-P) - - VCC-3 - V Short Circuit Current ISC VS = 26V - 35 - mA Typ Max Unit 2300 - HZ 1700 - HZ 1900 - HZ 1300 - HZ 0.1 - 15 KHZ - 10 - HZ AC ELECTRICAL CHARACTERISTICS Characteristic Output Frequencies (KA2418B) (T a = 25°C) Symbol fH1 fH2 Test Conditions Min VCC = 26V,R1 = 14KΩ VCC = OV - VCC = 6V Output Frequencies (KA2428) fH1 fH2 VCC = 26V,R1 = 14KΩ VCC = OV - VCC = 6V fH1 Range Sweep Frequency fH1R fS R1=27KΩ to 1.7KΩ R1=14KΩ, C1=100nF KA2418B/28 TONE RINGER WITH BRIDGE DIODE APPLICATION CIRCUIT R3 224 1uF, 250Vac 2.2K C2 R2 TIP 10K 8 6 7 10K 5 KA2418B/28 Piezo C3 10uF Vout + 1 2 3 4 1300Ω : 8Ω RING R1 12K C1 100nF Vs 4 f1 = 3.22 X 10 R1(K) F2 = 5 7 • f1 fs = Fig. DEVICE 1000 C1(nF) 2 KA2418B KA2428B FUNCTION 4 4 3.22 X 10 2.66 X 10 R1 (K) R1 (K) fH1 (R1 = 14KΩ) 2300 + 300 (HZ) 1900 + 100 (HZ) fH2 (R1 = 14KΩ) 1700 + 300 (HZ) 1300 + 100 (HZ) f1