UTC TEA1062/1062A LINEAR INTEGRATED CIRCUIT

UTC

UNISONIC TECHNOLOGIES CO., LTD.

QW-R108-001,A

LOW VOLTAGE TELEPHONE
TRANSMISSION CIRCUIT WITH
DIALLER INTERFACE

DESCRIPTION

The UTC TEA1062/1062A 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 (64k

)for

dynamic, magnetic or piezoelectric microphones.
*Asymmetrical high-impedance inputs (32k

)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

=15mA

typ. 3.8 V

Line current operating range[pin1]
normal operation
with reduced performance

line

11 to 140 mA
1 to 11 mA

Internal supply current

typ. 1mA

Supply current for peripherials
at I

line

=15 mA MUTE input LOW(1062 is HIGH)

VCC>2.2V
VCC>2.8V

typ. 1.8mA
typ. 0.7mA

Voltage amplification range
microphone amplifier
receiving amplififer

44 to 52 dB
20 to 39 dB

Line loss compansation
Amplification control range
Exchange supply voltage range
Exchange feeding bridge resistance range

exch

typ. 6 dB
36 to 60V
400 to 1000

Operating ambient temperature range

amb

-25 to +75

UTC TEA1062/1062A LINEAR INTEGRATED CIRCUIT

UTC

UNISONIC TECHNOLOGIES CO., LTD.

QW-R108-001,A

SUPPLY AND

REFERENCE

CONTROL
CURRENT

CURRENT

REFERENCE

LOW

VOLTAGE

CIRCUIT

REG

AGC

MUTE

DTMF

MIC-

MIC+

GAR

GAS1

GAS2

SLPE

STAB

Fig.1 Block Diagram

1 LN positive line terminal
2 GAS1 gain adjustment; transmitting amplifier
3 GAS2 gain adjustment; transmitting amplifier
4 QR 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

GAS1

GAS2

GAR

MIC-

MIC+

STAB

DTMF

MUTE

REG

AGC

SLPE

UTC TEA1062/1062A LINEAR INTEGRATED CIRCUIT

UTC

UNISONIC TECHNOLOGIES CO., LTD.

QW-R108-001,A

ABSOLUTE MAXIMUM RATINGS

PARAMETER TEST

CONDITIONS SYMBOL

MIN

MAX

UNIT

Positive Continuous Line Voltage

VLN

Repetitive Line Voltage During

Switch-On Or Line Interruption

VLN

13.2

Repetitive Peak Line Voltage for a 1 ms Pulse/5s

R10=13

R9=20

(see

Fig.15)

VLN

Line Current (1)

R9=20

Iline 140

Voltage on All Other Pins

VCC+0.7

-Vi

0.7

Total Power Dissipation(2)

R9=20

Ptot 640

Storage Temperature Range

Tstg

-40

+125

Operating Ambient Temperature Range

Tamb

-25

+75

Junction Temperature

+125

1. Mostly dependent on the maximum required T

amb

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

THERMAL RESISTANCE

From junction to ambient in free air Rth j-a = 75K/W

ELECTRICAL CHARACTERISTICS

(Iline=11 to 140mA;V

=0V;f=800Hz;T

amb

=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

MIC inputs open

line

=1mA V

1.6

line

=4mA V

1.9

line

=15mA V

3.55

4.0

4.25 V

line

=100mA V

4.9

5.7

6.5 V

line

=140mA V

7.5

Variation with Temperature

line

=15mA

-0.3

mV/K

Voltage Drop Over Circuit,

between LN and VEE with
External Resistor R

line

=15mA

(LN to REG)

=68k

3.5

line

=15mA

(REG to SLPE)

=39k

4.5

Supply Current

=2.8V I

0.9 1.35 mA

Supply Voltage Available for

Peripheral Circuitry

line

=15mA

TEA1062

=1.2mA;MUTE=HIGH V

2.2

2.7

=0mA;MUTE=HIGH V

3.4

TEA1062A

=1.2mA;MUTE=LOW V

2.2

2.7

=0mA;MUTE=LOW V

3.4

UTC TEA1062/1062A LINEAR INTEGRATED CIRCUIT

UTC

UNISONIC TECHNOLOGIES CO., LTD.

QW-R108-001,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+

Input impedance (sigle-ended)

MIC- or MIC+ to V

Common Mode Rejection Ratio

CMR

Voltage Gain

MIC+ or MIC- to LN

line

=15mA

R7=68k

50.5

52.0 53.5

Gain Variation with Frequency

at f=300Hz and f=3400Hz

w.r.t.800Hz

+-0.2

Gain Variation with Temperature

at -25

C and +75

w.r.t.25

without

R6;

line

=50mA

+-0.2

Dual-tone multi-frequency

input DTMF (pin 11)

Input impedance

20.7 k

Voltage Gain from DTMF to LN

line

=15mA

R7=68k

25.5

Gain Variation with Frequency

at f=300Hz and f=3400Hz

w.r.t.800Hz

+-0.2 dB

Gain Variation with Temperature

at -25

C and +75

w.r.t.25

line

=50mA

+-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

-8 0 dB

Sending Amplifier Output LN(pin 1)

Output Voltage

line

=15mA

THD=10%

(rms)

1.7 2.3 V

line

=4mA

THD=10%

(rms)

0.8 V

Noise output voltage

line

=15mA;

R7=68k

;

200

between

MIC- and MIC+;

psophometrically

weighted

(rms)

-69

dBmp

Receiving Amplifier Input IR (pin 10)

Input impedance

21 k

Receiving Amplifier Output QR (pin 4)

Output Impedance

Voltage gain from IR to QR

line

=15mA;

(from pin 9 to

pin 4 )=300

29.5

32.5

UTC TEA1062/1062A LINEAR INTEGRATED CIRCUIT

UTC

UNISONIC TECHNOLOGIES CO., LTD.

QW-R108-001,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

0.2

Gain Variation with Temperature

at-25

C and +75

w.r.t.25

without R6

line

=50mA

+-0.2 dB

Output Voltage

sinwave drive;

=0mA;THD=2%

R4=100k

line

=15mA

=150

(rms)

0.22

0.33 V

=450

(rms)

0.3 0.48

Output Voltage

THD=10%

R4=100k

=150

line

=4mA V

(rms)

15 mV

Noise Output Voltage

line

=15mA

R4=100k

open-circuit

psophometrically

weighted

RL=300

(rms)

Gain adjustment GAR (pin 5)

Gain Variation of Receiving

Amplifier Achievable by
Varying
R4 between GAR and QR

-11

Mute Input (pin 12)

Input Voltage(HIGH)

1.5 V

Input Voltage(LOW)

0.3

Input Current

MUTE

8 15

Reduction of Gain

MIC+ or MIC- to QR

MUTE=LOW

70 dB

Voltage Gain from DTMF to QR

MUTE=LOW

R4=100k

RL=300

-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

Gain Control Range

line

=70mA

-5.8

Highest Line Current

for Maximum Gain

line

Minimum Line Current

for Minimum Gain

line

UTC TEA1062/1062A LINEAR INTEGRATED CIRCUIT

UTC

UNISONIC TECHNOLOGIES CO., LTD.

QW-R108-001,A

FUNCTIONAL DESCRIPTION

Supply: VCC, LN, SLPE, REG and STAB

Power for the UTC TEA1062/1062A 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 TEA1062/1062A,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

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(R

exch

) and the DC resistance

of the telephone line(R

line

). The UTC

TEA1062/1062A has an internal current stabilizer
operating at a level determined by a 3.6k resistor
connected between STAB and VEE( see Fig.8).
When the line current(I

line

) 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

) the excess current is shunted to V

via LN.

The regulated voltage on the line terminal(V

) can be

calculated as:
V

ref

SLPE

*R9 or;

ref

+[(I

line

CC -

0.5*10-

A)I

]*R9

where:V

ref

is an internally generated temperature

compensated reference voltage of 3.7V and R9 is an
external resistor connected between SLPE and V

. In

normal use the value of R9 would be 20

. 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>=

+0.5mA +I

, 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 TEA1062/1062A has symmetrical inputs.
Its input impedance is 64k

(2*32k

) and its voltage

gain is typically 52 dB (when R7=68k

.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 TEA1062 is HIGH) level at MUTE
enables DTMF input and inhibites the microphone
inputs and the receiving amplifier inputs; a HIGH(UTC
TEA1062 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=68k

) 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=100k

). 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
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.

UTC TEA1062/1062A LINEAR INTEGRATED CIRCUIT

UTC

UNISONIC TECHNOLOGIES CO., LTD.

QW-R108-001,A

Automatic gain control input(AGC)

Automatic line loss compensation is achieved by
connecting a resistor(R6) between AGC and V

. 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

/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 Z

bal

,(see Fig.4) suppresses the transmitted signal

in the earpiece. Compensation is maximum when the
following conditions are fulfilled:
(a) R9*R2=R1[R3+(R8//Z

bal

)];

(b) [Z

bal

/(Z

bal

+R8)]=[Z

line

/(Z

line

+R1)];

If fixed values are chosen for R1, R2, R3 and R9 then
condition(a) will always be fullfilled when R8/Z

bal

lR3.

To obtain optimum side-tone suppression condition(b)
has to be fulfilled which results in:
Z

bal

=(R8/R1) Z

line

=k*Z

line

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)Z

bal

//R8R3 fulfilling condition (a) and thus

ensuring correct anti-sidetone bridge operation,
(c) Z

bal

+R8R9 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
Z

line

= 210

+(1265

//140nF) representing a 5km line

of 0.5 mm diameter, copper, twisted pair cable
matched to 600

(176

/km;38nF/km). When k=0.64

then R8=390

bal

=130

+(820

//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

). 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

for peripheral circuits depends on

the external components used. Fig.9 shows this
current for V

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

) connected between REG and

SLPE.

UTC TEA1062/1062A LINEAR INTEGRATED CIRCUIT

UTC

UNISONIC TECHNOLOGIES CO., LTD.

QW-R108-001,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 TEA1062 is

HIGH)

.curve(b) is valid when MUTE=HIGH

(UTC TEA1062 is LOW)

and the receiving amplifier is

driven;Vo(rms)=150mV,R

=150

.The supply possibilities can be increased simply by setting the voltage drop

over the circuit V

to a high value by means of resistor R

connected between REG and SLPE.

MIC+

MIC-

(1)

7
6

MIC+

MIC-

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

(mA)

cc(V)

(a) Ip=2.1mA
(b) Ip=1.7mA
Iline=15mA at V

=4V

R1=620

and R9=20

UTC TEA1062/1062A LINEAR INTEGRATED CIRCUIT

UTC

UNISONIC TECHNOLOGIES CO., LTD.

QW-R108-001,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 TEA1062 is LOW) or open-circuit, for measuring the DTMF input MUTE should be
LOW(UTC TEA1062 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|).

MIC-

MIC+

REG AGC STAB SLPE

GAS2

GAS1

GAR

VCC

VEE

DTMF

MUTE

R1 620

100

100pF

C7 1nF

100pF

100k

68k

3.6k

4.7

100

600

C8 1nF

10 TO 140 mA

MIC-

MIC+

REG AGC STAB

SLPE

GAS2

GAS1

GAR

VCC

VEE

DTMF

MUTE

R1=620

100

100pF

C7 1nF

100pF

100k

68k

3.6k

4.7

100

600

C8 1nF

10 TO 140 mA

UTC TEA1062/1062A LINEAR INTEGRATED CIRCUIT

UTC

UNISONIC TECHNOLOGIES CO., LTD.

QW-R108-001,A

Fig.15 Typical application of the UTC TEA1062A ,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

VCC

DTMF

VSS DP/FL

VDD

CARDLE

CONTRAT

TELEPHONE

LINE

BSN254A

UTC1062A

dialling

circuit

Fig.16 Typical applications of the UTC TEA1062/1062A (simplified)

The dashed lines show an optional flash ( register recall by timed loop break).

SLPE

GAS1

GAS2

REG

AGC

STAB V

DTMF

GAR

MIC-

MIC+

MUTE

Telephone

Line

From dial and

control circuits

100

620

R2
132k

BZX79

C12

R10
130

BAS11

(x2)

BZW14

(x2)

100nF

R3
3.92k

C4
100pF

C7
1nF

R8
390

Zbal

R9
20

100pF

1nF

(R16.R14)

4.7

3.6k

UTC TEAI062/A

Ð­Ð»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: UTCTEA1062/A

ÐÐ»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: UTCTEA1062/A