TEA1062AN

UTCTEA1062N UTC | Alldatasheet

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UTC UNISONIC TECHNOLOGIES CO., LTD. 1 QW-R108-011,A LOW VOLTAGE TELEPHONE TRANSMISSION CIRCUIT WITH DIALLER INTERFACE

DESCRIPTION

The UTC TEA1062N / TEA1062AN is a bipolar integrated circuit performing all speech and line interface function, required in the fully electronic telephone sets. It performs electronic switching between dialing speech. The circuit is able to operate down to D.C. line voltage of 1.6V (with reduced performance) to facilitate the use of more telephone sets in parallel.

FEATURES

• Low d.c. line voltage; operates down to 1.6V (excluding polarity guard). *Voltage regulator with adjustment static resistance. *Provides supply with limited current for external circuitry. *Symmetrical high-impedance inputs (64kΩ ) for dynamic, magnetic or piezoelectric microphones. *Asymmetrical high-impedance inputs (32kΩ ) for electret microphones. *DTMF signal input with confidence tone. DIP-16 SOP-16 *Mute input for pulse or DTMF dialing. *Receivering amplifier for several types of earphones. *Large amplification setting range on microphone and earpiece amplifiers. *Line loss compensation facility , line current depedant (microphone and earpiece amplifiers). *Gain control adaptable to exchange supply. *Possibility to adjust the d.c. line voltage. QUICK REFERENCE DATA Line voltage at I line= 1 5 m A V LN typ. 3.8 V Line current operating range[pin1] normal operation with reduced performance I line I line 11 to 140 mA 1 to 11 mA Internal supply current I CC t y p . 1 m A Supply current for peripherials a t I line=15 mA MUTE input LOW(1062 is HIGH) V C C > 2 . 2 V V C C > 2 . 8 V I p I p typ. 1.8mA typ. 0.7mA Voltage amplification range microphone amplifier receiving amplififer A VD A VD 44 to 52 dB 20 to 39 dB Line loss compansation Amplification control range Exchange supply voltage range Exchange feeding bridge resistance range A VD V exch R exch typ. 6 dB 36 to 60V 400 to 1000 Ω Operating ambient temperature range T amb - 2 5 t o + 7 5°C

UTC UNISONIC TECHNOLOGIES CO., LTD. 2 QW-R108-011,A dB SUPPLY AND REFERENCE CONTROL CURRENT CURRENT REFERENCE LOW VOLTAGE CIRCUIT 16815149 13 1 REG AGCVEE MUTE DTMF MIC- MIC+ IR VCC LN GAR QR GAS1 GAS2 SLPESTAB F i g . 1 B l o c k D i a g r a m

1 LN positive line terminal

2 GAS1 gain adjustment; transmitting amplifier

3 GAS2 gain adjustment; transmitting amplifier

4 Q R non-inverting output,receiving amplifier

5 GAR gain adjustment; receiving amplifier

6 MIC- inverting microphone input

7 MIC+ on-inverting microphone input

8 STAB current stabilizer

9 VEE negative line terminal

10 IR receiving amplifier input

11 DTMF dual-tone multi-frequency input

12 MUTE mute input

13 Vcc positive supply decoupling

14 REG voltage regulator decoupling

15 AGC automatic gain control input

16 SLPE slope (DC resistance) adjustment

Fig.2 PIN CONFIGURATIONS LN GAS1 GAS2 QR GAR MIC- MIC+ STAB V EE IR DTMF MUTE VCC REG AGC SLPE

UTC UNISONIC TECHNOLOGIES CO., LTD. 3 QW-R108-011,A ABSOLUTE MAXIMUM RATINGS PARAMETER TEST CONDITIONS SYMBOL MIN MAX UNIT Positive Continuous Line Voltage VLN 12 V Repetitive Line Voltage During Switch-On Or Line Interruption VLN 13.2 V Repetitive Peak Line Voltage for a 1 ms Pulse/5s R10=13Ω R9=20Ω (see Fig.15) VLN 28 V Line Current (1) R9=20Ω Iline 140 mA Voltage on All Other Pins Vi VCC+0.7 V -Vi 0.7 V Total Power Dissipation (2) R9=20Ω Ptot 640 mW Storage Temperature Range Tstg -40 +125 °C Operating Ambient Temperature Range Tamb -25 +75 °C Junction Temperature Tj +125 °C 1. Mostly dependent on the maximum required Tamb and the voltage between LN and SLPE (see Figs 6 ). 2. Calculated for the maximum ambient temperature specified T amb=75°C and a maximum junction temperature of 125°C. THERMAL RESISTANCE From junction to ambient in free air Rth j-a = 75K/W ELECTRICAL CHARACTERISTICS (Iline=11 to 140mA;VEE=0V;f=800Hz;Tamb=25°C; unless otherwise specified) PARAMETER TEST CONDITIONS SYMBOL MIN TYP MAX UNIT Supply; LN and VCC(pins 1 and 13) Voltage Drop Over Circuit, between LN and V EE MIC inputs open I line=1mA V LN 1.6 V I line=4mA V LN 1.9 V I line=15mA V LN 3.55 4.0 4.25 V I line=100mA V LN 4.9 5.7 6.5 V I line=140mA V LN 7.5 V Variation with Temperature I line=15mA ∆VLN/∆T -0.3 mV/K Voltage Drop Over Circuit, between LN and VEE with External Resistor R VA Iline=15mA RVA(LN to REG) =68kΩ 3.5 V I line=15mA RVA(REG to SLPE) =39kΩ 4.5 V Supply Current V CC=2.8V I CC 0.9 1.35 mA Supply Voltage Available for Peripheral Circuitry I line=15mA TEA1062N I p=1.2mA; MUTE=HIGH V CC 2.2 2.7 V l p=0mA;MUTE=HIGH V CC 3.4 V TEA1062AN I p=1.2mA; MUTE=LOW V CC 2.2 2.7 V l p=0mA;MUTE=LOW V CC 3.4 V

UTC UNISONIC TECHNOLOGIES CO., LTD. 4 QW-R108-011,A ELECTRICAL CHARACTERISTICS (continued) PARAMETER TEST CONDITIONS SYMBOL MIN TYP MAX UNIT Microphone inputs MIC+ and MIC- (pins 6 and 7) Input impedance (differential) between MIC- and MIC+ ｜Zi｜ 64 kΩ Input impedance (sigle-ended) M I C - o r M I C + t o VEE ｜Zi｜ 32 kΩ Common Mode Rejection Ratio k CMR 82 dB Voltage Gain M I C + o r M I C - t o L N I line=15mA R7=68k Ω Gv 50.5 52.0 53.5 dB Gain Variation with Frequency at f=300Hz and f=3400Hz w.r.t.800Hz ∆Gvf +-0.2 dB Gain Variation with Temperature a t - 2 5 °C and +75°C w.r.t.25 °C without R6; I line=50mA ∆GvT +-0.2 dB Dual-tone multi-frequency input DTMF (pin 11) Input impedance ｜Zi｜ 20.7 kΩ Voltage Gain from DTMF to LN I line=15mA R7=68k Ω Gv 24 25.5 27 dB Gain Variation with Frequency at f=300Hz and f=3400Hz w.r.t.800Hz ∆Gvf +-0.2 dB Gain Variation with Temperature a t - 2 5°C and +75°C w.r.t.25 °C I line=50mA ∆GvT +-0.2 dB Gain Adjustment GAS1 and GAS2 (pins 2 and 3) Gain Variation of the Transmitting Amplifier by Varying R7 between GAS1 and GAS2 ∆Gv -8 0 dB Sending Amplifier Output LN (pin 1) Output Voltage I line=15mA THD=10% V LN(rms) 1.7 2.3 V I line=4mA THD=10% V LN(rms) 0.8 V Noise output voltage I line=15mA; R7=68k Ω ; 200 Ω between MIC- and MIC+; psophometrically weighted V NO(rms) -69 dBmp Receiving Amplifier Input IR (pin 10) Input impedance ｜Zi｜ 21 kΩ Receiving Amplifier Output QR (pin 4) Output Impedance ｜Zo｜ 4 Ω Voltage gain from IR to QR I line=15mA; R L(from pin 9 to pin 4 )=300 Ω Gv 29.5 31 32.5 dB

UTC UNISONIC TECHNOLOGIES CO., LTD. 5 QW-R108-011,A ELECTRICAL CHARACTERISTICS (continued) PARAMETER TEST CONDITIONS SYMBOL MIN TYP MAX UNIT Gain Variation with Frequency at f=300Hz and f=3400Hz w.r.t.800Hz ∆Gvf ±0.2 dB Gain Variation with Temperature a t - 2 5°C and +75°C w.r.t.25 °C without R6 I line=50mA ∆GvT +-0.2 dB Output Voltage sinwave drive; I p=0mA;THD=2% R4=100k Ω I line=15mA R L=150Ω VO(rms) 0.22 0.33 V R L=450Ω VO(rms) 0.3 0.48 V Output Voltage THD=10% R4=100k Ω R L=150Ω I line=4mA V O(rms) 15 mV Noise Output Voltage I line=15mA R4=100k Ω IR open-circuit psophometrically weighted RL=300 Ω VNO(rms) 50 μV Gain adjustment GAR (pin 5) Gain Variation of Receiving Amplifier Achievable by Varying R4 between GAR and QR v -11 dB Mute Input (pin 12) Input Voltage(HIGH) V IH 1.5 V CC V Input Voltage(LOW) V IL 0.3 V Input Current I MUTE 8 15 μA Reduction of Gain MIC+ or MIC- to QR MUTE=LOW ∆Gv 70 dB Voltage Gain from DTMF to QR MUTE=LOW R4=100k Ω RL=300 Ω Gv -19 dB Automatic Gain Control Input AGC ( pin 15) Controlling the Gain from lR to QR and the Gain from MIC+/MIC- to LN;R6 between AGC and VEE R6=110k Ω Gain Control Range I line=70mA ∆Gv - 5 . 8 d B Highest Line Current f o r M a x i m u m G a i n I line 23 mA Minimum Line Current f o r M i n i m u m G a i n I line 61 mA

UTC UNISONIC TECHNOLOGIES CO., LTD. 6 QW-R108-011,A FUNCTIONAL DESCRIPTION Supply: VCC, LN, SLPE, REG and STAB Power for the UTC TEA1062N/TEA1062AN and its peripheral circuits is usually obtained from the telephone line. The IC supply voltage is derived from the line via a dropping resistor and regulated by the UTC TEA1062N/TEA1062AN,The supply voltage Vcc may also be used to supply external circuits e.g. dialling and control circuits. Decoupling of the supply voltage is performed by a capacitor between Vcc and V EE while the internal voltage regulator is decoupled by a capacitor between REG and V EE. The DC current drawn by the device will vary in accordance with varying values of the exchange voltage(V exch), the feeding bridge resistance(Rexch) and the DC resistance of the telephone line(R line). The UTC TEA1062N/TEA1062AN has an internal current stabilizer operating at a level determined by a 3.6k Ω resistor connected between STAB and VEE( see Fig.8). When the line current(Iline) is more than 0.5 mA greater than the sum of the IC supply current ( Icc) and the current drawn by the peripheral circuitry connected to V CC(lp) the excess current is shunted to V EE via LN. The regulated voltage on the line terminal(V LN) can be calculated as: V LN=Vref+ISLPE*R9 or; V LN=Vref+[(Iline – ICC - 0.5*10-3A)－Ip]*R9 where:Vref is an internally generated temperature compensated reference voltage of 3.7V and R9 is an external resistor connected between SLPE and V EE. In normal use the value of R9 would be 20 Ω . Changing the value of R9 will also affect microphone gain, DTMF gain,gain control characteristics, side tone level, maxmimum output swing on LN and the DC characteristics (especially at the lower voltages). Under normal conditions, when I SLPE>=ICC+0.5mA +I p, the static behaviour of the circuit is that of a 3.7V regulator diode with an internal resistance equal to that of R9.In the audio frequency range the dynamic impedance is largely determined by R1.Fig.3 shows the equivalent impedance of the circuit. Microphone inputs(MIC+ and MIC-) and gain pins (GAS1 and GAS2) The UTC TEA1062N/TEA1062AN has symmetrical inputs. Its input impedance is 64k Ω (2*32kΩ ) and its voltage gain is typically 52 dB (when R7=68k Ω .see Fig.13). Dynamic, magnetic, piezoelectric or electret (with built-in FET source followers) can be used. Microphone arrangements are illustrated in Fig.10. The gain of the microphone amplifier can be adjusted between 44dB and 52dB to suit the sensitivity of the transducer in use. The gain is proportional to the value of R7 which is connected between GAS1 and GAS2. Stability is ensured by the external capacitors, C6 connected between GAS1 and SLPE and C8 connected between GAS1 and VEE. The value of C6 is 100pF but this may be increased to obtain a first-order low-pass filter. The value of C8 is 10 times the value of C6. The cut-off frequency corresponds to the time constant R7*C6. Mute input (MUTE) A LOW(UTC TEA1062N is HIGH) level at MUTE enables DTMF input and inhibites the microphone inputs and the receiving amplifier inputs; a HIGH(UTC TEA1062N is LOW) level or an open circuit does the reverse. Switching the mute input will cause negligible clickis at the telephone outputs and on the line. In case the line current drops below 6mA(parallal opration of more sets) the circuit is always in speech condition independant of the DC level applied to the MUTE input. Dual-tone multi-frequency input (DTMF) When the DTMF input is enabled dialling tones may be sent onto the line. The voltage gain from DTMF to LN is typically 25.5dB(when R7=68kΩ ) and varies with R7 in the same way as the microphone gain. The signalling tones can be heard in the earpiece at a low level(confidence tone). Receiving amplifier (IR,QR and GAR) The receiving amplifier has one input (IR) and a non-inverting output (QR). Earpiece arrangements are illustrated in Fig.11. The IR to QR gain is typically 31dB (when R4=100kΩ ). It can be adjusted between 20 and 31dB to match the sensitivity of the transducer in use. The gain is set with the value of R4 which is connected between GAR and QR.The overall receive gain, between LN and QR, is calculated by substracting the anti-sidetone network attenuation (32dB) from the amplifier gain. Two external capacitors, C4 and C7, ensure stability. C4 is normally 100pF and C7 is 10 times the value of C4. The value of C4 may be increased to obtain a first-order low-pass filter.The

UTC UNISONIC TECHNOLOGIES CO., LTD. 7 QW-R108-011,A cut-off frequency will depend on the time constant R4*C4. The output voltage of the receiving amplifier is specified for continuous-wave drive. The maximum output voltage will be higher under speech conditions where the peak to RMS ratio is higher. Automatic gain control input (AGC) Automatic line loss compensation is achieved by connecting a resistor(R6) between AGC and V EE. The automatic gain control varies the gain of the microphone amplifier and the receiving amplifier in accordance with the DC line current. The control range is 5.8dB which corresponds to a line length of 5km for a 0.5mm diameter twisted pair copper cable with a DC resistance of 176 Ω /km and average attenuation of 1.2dB/km. Resistor R6 should be chosen inaccordance with the exchange supply voltage and its feeding bridge resistance(see Fig.12 and Table 1). The ratio of start and stop currents of the AGC curve is independent of the value of R6. If no automatic line loss compensation is required the AGC may be left open-circuit. The amplifier, in this condition, will give their maximum specified gain. Side-tone suppression The anti-sidetone network, R1//Z line, R2, R3, R8, R9 and Zbal,(see Fig.4) suppresses the transmitted signal in the earpiece. Compensation is maximum when the following conditions are fulfilled: ( a ) R 9 * R 2 = R 1 [ R 3 + ( R 8 / / Z bal)]; ( b ) [ Z bal/(Zbal+R8)]=[Zline/(Zline+R1)]; If fixed values are chosen for R1, R2, R3 and R9 then condition(a) will always be fullfilled when R8/Z ball《R3. To obtain optimum side-tone suppression condition(b) has to be fulfilled which results in: Z bal=(R8/R1) Zline=k*Zline where k is a scale factor; K=(R8/R1). The scale factor (k), dependent on the value of R8, is chosen to meet following criteria: (a) Compatibility with a standard capacitor from the E6 or E12 range for Z bal, (b)｜Zbal//R8｜《R3 fulfilling condition (a) and thus ensuring correct anti-sidetone bridge operation, (c) ｜Zbal+R8｜》R9 to avoid influencing the trans- mitter gain. In practice Z line varies considerably with the type and length. The value chosen for Z bal should therefore be for an average line length thus giving optimum setting for short or long lines. Example The balance impedance Z bal at which the optimum suppression is present can be calculated by: Suppose Zline = 210 Ω +(1265Ω //140nF) representing a 5km line of 0.5 mm diameter, copper, twisted pair cable matched to 600 Ω (176Ω /km;38nF/km). When k=0.64 then R8=390 Ω ,Zbal=130Ω +(820Ω //220nF). At line currents below 9mA the internal reference voltage is automatically adjusted to a lower value(typically 1.6V at 1mA) This means that more sets can be operated in parallel with DC line voltages (excluding the polarity guard) down to an absolute minimum voltage of 1.6V. With line currents below 9mA the circuit has limited sending and receiving levels. The internal reference voltage can be adjusted by means of an external resistor(R VA). This resistor when connected between LN and REG will decrease the internal reference voltage and when connected between REG and SLPE will increase the internal reference voltage. Current(I available from V CC for peripheral circuits depends on the external components used. Fig.9 shows this current for V CC > 2.2V. If MUTE is LOW (1062 is HIGH) when the receiving amplifier is driven the available current is further reduced. Current availability can be increased by connecting the supply IC(1081) in parallel with R1, as shown in Fig.16(c), or, by increasing the DC line voltage by means of an external resistor(R VA) connected between REG and SLPE.

UTC UNISONIC TECHNOLOGIES CO., LTD. 8 QW-R108-011,A LN VEE Leq Vref Rp R1 C3 C1 100 µF4.7 µF REG V CC 20Ω Rp=16.2kΩ Leq=C3*R9*Rp Fig.3 Equivalent impedance circuit The anti-sidetone network for the UTCTEA1062N/TEA1062AN family shown in Fig.4 attenuates the signl received from the line by 32 dB before it enters the receiving amplifier. The attenuation is almost constant over the whole audio frequency range. Fig.5 shows a convertional Wheatstone bridge anti-sidetone circuit that can be used as an alternative. Both bridge types can be used with either resistive or complex set impedances. Zline Zbal Rt IR VEE SLPE im Fig 4 Equivalent circuit of UTC TEA1062N/TEA1062AN anti-sidetone bridge Zline Rt IR VEE SLPE im RA Fig 5 Equivalent circuit of an anti-sidetone network in a wheatstone bridge configuration

UTC UNISONIC TECHNOLOGIES CO., LTD. 9 QW-R108-011,A 150 130 110 2468 1 0 1 2 (1) (2) (3) (4) VLN-VSLPE(V) Iline (mA) (1) 45°C 1068mW (2) 55°C 934mW (3) 65°C 800mW (4) 75°C 666mW Tamb Ptot Fig.6 UTC TEA1062N/TEA1062AN safe operating area Fig.8 Supply arrangement DC AC REG STAB SLPE VEE VCCLN Rexch Vexch Rline Iline R1 C3 R5 R9 PERIPHERAL CIRCUITS 0.5mA ISLPE ISLPE 0.5mA

UTC UNISONIC TECHNOLOGIES CO., LTD. 10 QW-R108-011,A Fig.9 Typical current Ip available from Vcc peripheral circuitry with Vcc>=2.2V. curve (a) is valid when the receiving amplifier is not driven or when MUTE =LOW (UTC TEA1062N is HIGH) .curve(b) is valid when MUTE=HIGH(UTC TEA1062N is LOW) and the receiving amplifier is driven; Vo(rms)=150mV,RL=150Ω .The supply possibilities can be increased simply by setting the voltage drop over the circuit VLN to a high value by means of resistor RVA connected between REG and SLPE. MIC+ MIC- (1) MIC+ MIC- VEE VCC

6 MIC-

(a) (b) (c) Fig. 10 Alternative microphone arrangement (a) Magnetic or dynamic microphone. The resistor marked(1) may be connected to decrease the terminating impedance. (b) Electret microphone. (c) Piezoelectric microphone. 0.8 1.6 2.4 Ip (mA) 012 34 5 a b Vcc(V) (a) Ip=2.1mA (b) Ip=1.7mA Iline=15mA at VLN=4V R1=620Ω and R9=20Ω

UTC UNISONIC TECHNOLOGIES CO., LTD. 11 QW-R108-011,A (a) Dynamic earpiece. (b) Magnetic earpiece.The resistor marked(1) may be connected to prvent distortion(inductive load) (c) Piezoelectric earpiece.The earpiece marked(2) is requirred to increase the phase margin (capacitive load) Fig.12 Variation of gain with line urrent,with R6 as a parameter. Rexch(Ω ) 400 600 800 1000 R6(kΩ ) 36 100 78.7 × × Vexch(V) 48 140 110 93.1 82 60 × × 120 102 Table 1 Values of resistor R6 for optimum line loss compensation,for various usual values of exchange supply vloltage(Vexch) and exchange feeding bridge resistance(Rexch);R9=20 Ω . QR VEE 9 4 QR VEE QR VEE (2)(1) (a) (b) (c) Fig.11 Alternative receiver arrangement 0 20 40 60 80 100 120 140 Iline (mA) →Gv (dB) R6=﹢ R9=20Ω 78.7kΩ 110kΩ 140kΩ (1) (2) (3) (3) (1) (2) R6= R6= R6=

UTC UNISONIC TECHNOLOGIES CO., LTD. 12 QW-R108-011,A Fig.13 Test circuit defining voltage gain of MIC+,MIC- and DTMF inputs. Voltage gain is defined as : GV=20*log(|VO/Vi|).For measuring the gain from MIC+ and MIC- the MUTE input should be HIGH(UTC TEA1062N is LOW) or open-circuit, for measuring the DTMF input MUTE should be LOW(UTC TEA1062N is HIGH) .Inputs not under test should be open-circuit. Fig.14 Test circuit for defining voltage gain of the receiving amplifier. Voltage gain is defined as: GV=20*log(|VO/Vi|). 13 1 16815149 MIC- MIC+ REG AGC STAB SLPE GAS2 GAS1 GAR QR LNVCC VEE IR DTMF MUTE R1 620Ω 100 µ F 100pF C7 1nF 100pF 100kΩ 68kΩ 20Ω 3.6kΩ R6C3 4.7 µ F 10 µ F 100 µ F Vi Vi RL 600Ω C8 1nF

10 TO 140 mA

R1=620Ω 100 µF 100pF C7 1nF 100pF 100kΩ 68kΩ 20Ω 3.6kΩ R6C3 4.7 µF 10 µF 100µF Vi 600Ω C8 1nF

UTC UNISONIC TECHNOLOGIES CO., LTD. 13 QW-R108-011,A Fig.15 Typical application of the UTC TEA1062AN ,shown here with a piezoelectric earpiece and DTMF dialling. The bridge to the left ,the Zener diode and R10 limit the current into the circuit and the voltage across the circuit during line transients.Pulse dialling or register recall required a different protection arrangement. The DC line voltage can be set to a higher value by resistor RVA(REG to SLPE). VEE DTMF MUTE LN VCC DTMF VSS DP/FL VDD CARDLE CONTRAT TELEPHONE LINE BSN254A UTC TEA1062AN dialling circuit Fig.16 Typical applications of the UTC TEA1062N/TEA1062AN (simplified) The dashed lines show an optional flash (register recall by timed loop break). SLPE GAS1 GAS2 REG AGC STAB V EE DTMF VCCLN IR QR GAR MIC- MIC+ MUTE Telephone Line From dial and control circuits 100 µF 16 14 15 620Ω 132k ΩBZX79 C12 R10 130Ω BAS11 (x2) BZW14 (x2) 100nF 3.92kΩ 100pF 1nF 390 Ω Zbal R9 20Ω 100pF R7 1nF RVA(R16.R14) 4.7 µF R6 R5 3.6kΩ UTC TEAI062N UTC TEA1062AN