UTC 31002A LINEAR INTEGRATED CIRCUIT TELEPHONE TONE RINGER DESCRIPTION The UTC 31002A is a bipolar integrated circuit designed for telephone bell replacement. It can also be used as alarms or other alerting devices. SOP-8 FEATURES *Designed for telephone bell replacement. *Low current drain for multiple extension of lines. *Adjustable 2-frequency tone. *Adjustable warbling rate. *Built-in hysteresis prevents false triggering and rotary dial 'CHIRPS'. *Programmable for initiation current by simple external resistor DIP-8 PIN CONFIGURATIONS Vcc 1 8 RSL 2 7 High Freq. Time Constant 3 6 High Freq. Time Constant 4 5 Low Freq. Time Constant Low Freq. Time Costant Output GND ABSOLUTE MAXIMUM RATINGS(Ta=25°C ) PARAMETER Supply Voltage Power Dissipation Operating Temperature Storage Temperature UTC SYMBOL VALUE UNIT Vcc Pd Topr Tstg 30 400 -45 to 85 -65 to 150 V mW °C °C UNISONIC TECHNOLOGIES CO., LTD. 1 QW-R108-005,A UTC 31002A LINEAR INTEGRATED CIRCUIT BLOCK DIAGRAM R2 4 3 C2 R3 C3 6 HIGH OSC LOW OSC 1 7 AMP 8 OUTPUT POWER SUPPLY (WITH HYSTERESIS) 5 2 Note:R2,R3,C2 and C3 are parts externally mounted ELECTRICAL CHARACTERISTICS( Ta=25°C, all voltage referenced to GND unless otherwise specified) PARAMETER SYMBOL Operating Supply Voltage Initiation Supply Voltage (note 1) Initiation Supply Current (note 1) Sustaining Voltage (note 2) Sustaining Current (note 2) Output Voltage High Vcc Vsi Isi Vsus Isus VOH Output Voltage Low VOL IIN(Pin 3) IIN(Pin 7) High Frequency 1 High Frequency 2 Low Frequency FH1 FH2 FL TEST CONDITIONS See Fig.2 6.8K-Pin 2 to GND See Fig.2 No Load Vcc=Vsus,See Fig.2 Vcc=21V, I8=-15mA Pin6=6V, Pin7=GND Vcc=21V, I8=15mA Pin6=GND, Pin7=6V Pin3=6V, Pin4=GND Pin7=6V, Pin6=GND R3=191K, C3=6800pF R3=191K, C3=6800pF R2=165K, C2=0.47µF MIN 17 1.4 9.7 0.7 17.0 461 576 9.0 TYP MAX UNIT 19 2.8 11.0 1.4 19.0 29.0 21 4.2 12.0 2.5 21.0 V V mA V mA V 1.6 V 500 500 563 704 11.0 nA nA Hz Hz Hz 512 640 10 *NOTE (See electrical characteristics sheet) 1. Initiation supply voltage (Vsi) is the supply voltage required to start the tone ringer oscillating. 2. Sustaining voltage (Vsus) is the supply voltage required to maintain oscillation. UTC UNISONIC TECHNOLOGIES CO., LTD. 2 QW-R108-005,A UTC 31002A LINEAR INTEGRATED CIRCUIT APPLICATION NOTE The application circuit illustrates the use of the UTC 31002A device in typical telephone tone ringer application. The AC ringer signal voltage appears across the TIP and RING inputs of the circuit and is attenuated by capacitor C1 and resistor R1. C1 also provides isolation from DC voltage (48V) on the exchanged line. After full wave rectification by the bridge diode, the wave form is filtered by capacitor C4 to provide a DC supply for the tone ringer chip. As this voltage exceeds the initiation voltage (Vsi), oscillation starts. With the components shown , the output frequency chops between 512Hz (FH1) and 640 Hz(FH2) at a 10 Hz(FL) rate. The loudspeaker load is coupled through a 1300Ω to 8Ω transformer. The output coupling capacitor C5 is required with transformer coupled loads. When driving a pizeo-ceramic transducer type load, the coupling C5 and transformer (1300Ω:8Ω) are not required. However, a current limiting resistor is required. The low frequency oscillator oscillates at a rate (FL ) controlled by an external resistor (R2) and capacitor (C2). The fequency can be determined using the relation FL=1/1.289 R2* C2. The high frequency oscillates at a FH1,FH2 controlled by an external resistor (R3) and capacitor (C3). The frequency can be determined using the relation FH1=1/1.504 R3*C3 and FH2= 1/1.203 R3*C3. Pin 2 of the UTC 31002A allows connection of external resistor RSL, which is used to program the slope of the supply current vs. supply voltage characteristics (see Fig.3), and hence the supply current up to the initiation voltage (Vsi). This initiation voltage remains constant independent of RSL. The supply current drawn prior to triggering varies inversely with RSL, decreasing for increasing value of resistance. Thus, increasing the value of RSL, will decrease the amount of AC ringing current required to trigger the device. As such, longer sucribser loops are possible since less voltage is dropped per unit length of loop wire due to the lower current level. RSL can also be used to compensated for smaller AC coupling capacitors (C5 on Fig.4) (higher impedance) to the line which can be used to alter the ringer equivalence number of a tone ringer circuit. The graph in Fig.3 illustrates the variation of supply current with supply voltage of the UTC 31002A. Three curves are drawn to show the variation of initiation current with RSL. Curve B ( RSL=6.8K) shows the I-V characteristic for UTC 31002A tone ringer. Curve A is a plot with RSL<6.8KΩ UTC and shows an increase in the current drawn up to the initiation voltage Vsi. The I-V characteristic after initiation remains unchanged. Curve C illustrates the effect of increasing RSL above 6.8K initiation current decreases but again current alter triggering is unchanged. UNISONIC TECHNOLOGIES CO., LTD. 3 QW-R108-005,A UTC 31002A LINEAR INTEGRATED CIRCUIT Circuit Current-Supply Voltage (No Load) Supply Current Vs. Supply Voltage (No Load) 8.5 4.0 7.5 Supply Current (mA) Icc(mA),Supply Current 3.5 3.0 2.5 2.0 1.5 6.5 5.5 4.5 A:RSL=5K 3.5 B:RSL=6.8K 2.5 C:RSL=13K 1.0 1.5 0.5 0.5 2 6 10 14 18 22 26 30 34 2 6 Vcc(V),Supply voltage 10 14 18 22 26 30 34 Vcc(V),Supply voltage Fig.2 Fig. 3 APPLICATION CIRCUIT TIP C1 0.9 µF R1 560Ω C5 0.22 µF 1 8 2 7 10k 5.6k - 1 M UTC 31002A RING 3 C4 22 µF/35V 6 C3 6.9nF+-5% R2 4 D1 29V R3 191k+-1% SP 5 165k+-1% C2 0.47µF+-5% 15k 1300:8 Ω Fig.4 UTC UNISONIC TECHNOLOGIES CO., LTD. 4