Page 1
SPEECH CIRCUIT WITH POWER MANAGEMENT
2/4 WIRESINTERFACE WITH
- double antisidetonenetwork
- AC impedance externallyprogrammable
- Rx output dynamic programmable
- AGC attack-disconnectpointsprogrammable
ANTI-CLIPPING/ANTI DISTORTION CIRCUIT
PROGRAMMABLE
DTMF INTERFACE
3.3 VOLTS SUPPLY FOR MICROPROCESSOROR DIALER
EXTRA CURRENT SUPPLY PROGRAMMABLE FOR LOUDSPEAKER
DC CHARACTERISTIC PROGRAMMABLE
FORALL SPECIFICATION
LOW CURRENT OPERATION
TEA7063
PRELIMINARY DATA
DIP20 SO20
ORDERING NUMBERS:
TEA7063FP TEA7063DP
DESCRIPTION
The TEA7063 is designed to meet the different
BLOCK DIAGRAM
worldwide specifications for telephone set in mediumand high range equipments.
January1994
This is advanced information on anew product now in development or undergoing evaluation. Details are subject to change without notice.
1/15
Page 2
TEA7063
PIN CONNECTION (Top view)
LONG LINE SIDETONE
SHORT LINE SIDETONE
IMPEDANCE
BUFFER OUTPUT
V-REF
DTMF INPUT
MICROPHONE INPUT
I-REF
I START
1
2
3
4
5
6
7
8
9 CURRENT SUPPLY FOR L.S. AMP
19
18
17
16
15
14
13
12
EARPHONE20
MICROCONTROLLER POWER SUPPLY
NOISE FILTER
V-CAPA
V-LINE
I SLOPE
MIC/MIC-EARPHONE MUTE
GND
SQUEEZING THRESHOLD 10 SOFT-CLIPPING FILTER11
D93TL021
ABSOLUTE MAXIMUM RATINGS
Symbol Parameter Value Unit
Max. Current DC (steady) 150 mA
Max. Voltage AC (steady) 7.5 V
Max. Voltage AC + DC (steady) 9 V
Max. Current (20ms) ONE SHOT 1 A
Max. Voltage (20ms) ONE SHOT current < 1A 12 V
P
T
Total Power Dissipation 1 W
tot
Junction Temperature 130 °C
J
MAXIMUMOPERATING CONDITION
Symbol Parameter Value Unit
V
V
I
T
2/15
DC Voltage 7 V
DC
AC Voltage 2.2 Vp
AC
DC Current 110 mA
DC
Temperature Range -20to 70 °C
OP
Page 3
TEST CIRCUIT
TEA7063
R4 = 75
R5 = 5.1K
R6 = 22K
R9 = 100K
R11 = 140K
R12 = 0
R13 = 2.7K
R14 = 0
R15 = 140K
R16 = 2.7K
R17 = 1.8K
R18 = 560K
C1 = 47µF
C2 = 4.7µF
C3 = 47µF
C4 = 470nF
C5 = 100µF
C6 = 47pF
C7 =47pF
C8 =2.2nF
C9 =2.2nF
C10 =150nF
RLL =150K
RLS = 100K
RST= 330K
3/15
Page 4
TEA7063
ELECTRICAL CHARACTERISTICS (T
=25°C; f = 1KHz; R9 = 100KΩ; unless otherwise specified)
amb
Symbol Parameter Test Condition Min. Typ. Max. Unit
V
Iint Internal Bias Current (pin 17) I
V
I
ref
V
mp
I
cmp
I
spm
I
imp
I
ea
V
mh
V
mb
V
mh
V
mb
I
mleak
G
AGC
G
THD
Z
N
Stabilized Voltage (pin 17) IL= 25mA; R9 = 100KΩ 2.25 2.5 2.75 V
C
= 25mA
L
I
= 25mA; R9 = 180K
L
(V16 - R6*Iint +V
Reference Voltage IL= 25mA 1.05 1.2 1.35 V
ref
Current at V
ref
)
C
120 140
105
-100 +10 µA
160 µA
Stabilized Supply at pin 19 3.1 3.3 3.5 V
Charging Current at Pin19 Pin 17 = GND 0.6 X
I
line
Static Currentat Pin 19 IL= 25mA; R9 = 100KΩ 1.1 1.5 mA
= 25mA; R9 = 180KΩ 0.85 mA
I
L
Internal Consumption 80 110 150 µA
Supply Current for Parallel
Circuits (pin12)
Mute Microphone (pin 14) ON
Mute Earphone (pin 14) ON
IL= 25mA
I
= 75mA
L
OFF
OFF
10
50
12
57
1.6
0.25 0.8
2.7
0.25 2.1
Mute Leakage Current (pin14) V14=5V 20 µA
Tx Gain Long Line IL= 25mA 41.5-742.5-643.5
S
S
f DTMF Gain Pin 14 > 1.6V 41.5 42.5 43.5 dB
m
Tx Distortion IL= 25mA
S
Microphone Impedance 20 KΩ
e
Tx Noise (psometric) IL= 25mA
Tx
V
= -3dBm -GS
mic
V
= -3dBm -GS + 15dB
mic
-74 dBm
-5
3
10
2KΩ at Pins 5-7
R
Tx Attenuation in Mute Mode IL= 25mA
S
60 dB
Pin 14 > 1.6V
G
AGC
THD
N
R
Rx Gain Long Line
r
Line Lenght
r
Rx Distortion IL= 25mA
r
IL= 25mA 29
-7
30
-6
Vro = 500mV
Vro = 630mV
Rx Noise IL= 25mA -74 dBmp
Rx
Rx Attenuationin Mute Mode IL= 25mA
r
50 dB
31
-5
3
10
Pin = 14 > 2.7V
G
Z
G
Antisidetone IL= 25mA 22 dB
as
AC Impedance IL= 25mA 500 650 800 Ω
ac
Confidence Level = V
rs
LINE/VREC
Pin 14 > 2.7V 35.5 38.5 41.5 dB
(in DTMF)
I
ST
Soft Clipping Current Level
Control (pin 10)
V
ST
Control Voltage Range (Pin10) VST=R
IL= 25mA; R9 = 100KΩ
I
= 25mA; R9 = 180KΩ
L
I
x
ST
ST
2.30 2.55
2.80 mA
1.4
01V
µA
mA
mA
mA
V
V
V
V
dB
dB
%
%
psoph
dB
dB
%
%
µA
4/15
Page 5
TEA7063
CIRCUITDESCRIPTION
1. DC CHARACTERISTICS
1.1 V
(pin 17)
C
The stabilized voltage VC is connected to Vline
(pin 16) through an internal shunt regulator T1,
T2, which presents to the line a high AC impedance at frequecncies higher than 200Hz. At this
purpose the value of C1 (at pin 17) must be not
lower than 47µF (suggestedvalue is 100µF).
The shunt regulator, T1 and T2, also controls the
extra current source, or power management, at
pin 12 (see also paragraph6).
LINE
(pin 16)
1.2 V
The line voltage (pin 16) is determined by the
value of the external resistor R6 and by the internal current, I
, flowing between VC(pin 17) and
int
Figure1
Ground(seealso paragr.: 1.1):
V
LINE=VC
+R6 xI
int
VCis fixedby design at about2.5V.
I
is reversely related to R9:
int
I
= 8 Volt/R9 + 60µAatIL> 25mA
int
I
= 4 Volt/R9 + 60µAatIL= 6mA
int
where I
depends on ILB(see supply manage-
L
ment)
V
must be externally adjusted (with R6) to
LINE
guarantee both DC and AC characteristic in accordance to the specific standard of the different
adminastrations.
Another adjustment of the DC characteristic is
possible with R9. Increasing the value of R9
causes a decrease of I
duction of the product I
and consequently a re-
int
x R9. (see also Para-
int
graph7)
Figure2
5/15
Page 6
TEA7063
2. TRANSMISSIONCHAIN
2.1 A.G.C. In Transmission
The transmission gain between Microphone Input
(pin 7) and Vline (pin 16) is internally decreased
of 6dB when the line current varies from ILL to
ILS with a constantAC loadof 600Ω.
Thevalues of ILL (long line current) and ILS (short
line current) are programmable throughI-start (pin
9) and I-slope(pin15) (seealsoparagr.4).
2.2 Sending Impedance
Theimpedanceof the OutputStage Amplifier, Z
out
isdeterminedby theimpedanceZ4 (at pin3).
Z
=10.65 xZ4
out
The total AC impedance shown to the line is the
parallel
Z
par=Zout
//Z
//Z
int
ext
where:
Figure3
-Z
= 10KΩ//8.5 nF(internal)
int
-Z
= R6//C4 (at pin16)
ext
2.3 Sending Mute
In normal speech operation (V
mute
0.8V), the signal at Microphone Input (pin 7) is
amplified to V
(pin 16) with the gain Gs (long
line
line) or 6dB lower (shorter lines) depending on
AGC control (see paragr. 4).
In sending mute condition (V 14 > 1.6V) these
gains are reduced of at least 60dB. In the same
condition, DTMF input (pin 6) is activated, with
gain Gmf to the line independentfrom I
,
2.4 Antisidetone Buffer
The signal coming from the sending preamplifier
is internally presented at pin 4 and than buffered
to pins 1 and 2 for sidetone cancellation (see
paragraph3.2).
at pin 14 <
lenght.
line
6/15
Page 7
TEA7063
2.5 Soft Clipping
To avoid distortion on line, the TEA7063 has a
”soft clipping”on transmit channel.
The resistor (Rsoft) on pin 10 fixes the maximum
AC peak dynamicon theline: V
V
(Vp) = Vpin16(DC)-1.44 •
STL
STL
R
soft
R9 ( pin
( pin 10 )
8)
Figure4
whereRsoft ≤
1V
I
ST
IST=
470mV
⋅ R9 (pin8)
2
The capacitor (C10) and the resistor (R10) connected on pin 11 fixe the constant time of the soft
clipping.
Recommendedvalues: C10 = 150nF;
R10 = 560KΩ
Figure5: TransmitCurves
7/15
Page 8
TEA7063
3. RECEIVE CHAIN
3.1 A.G.C. In Receive
As described for the transmissionchain, also the
receiving gains Gr, from pins 1 and 2 to pin 20,
have a reduction of 6dB when Iline moves from
ILL to ILS (seealso paragr.4).
3.2 Sidetone Compensation
The circuitis providedwith a double anti-sidetone
networkto optimize both at longand short lines.
In case double antisidetone network is not requested by the application needs, pins 1 and 2
can be connected to each other and 5 external
passive components can be saved (ZALL and
ZRL).
Before entering pins 1 and 2, the received signal
isareduced by the two attenatingnetworks:
- ZALL/ZRL to pin 1 for long lines sidetone compensation,
- ZALS/ZRS to pin 2 for short lines sidetone compensation.
ZRL and ZRSdefine the totalreceive gains:
a)
b)
V20
V16
= G
r
ZRL
•
ZRL + ZALL
for
longlines
The equivalent balancing impedance is given by
the formula:
ZAL = K • ZALS +(1 - K) • ZALL
where:
-K = 0 at I
=ILL or lower (long line)
LINE
-K varies linearly from 0 to 1 with Iline between
ILL and ILS
-K = 1 at I
=ILS or higher (short line)..
LINE
Calculationstodefine ZALLand ZALS are:
a)
ZALL =70•R5•
b)
ZALL =70• R5 •
where:
-Z
= R6//C4//(Zelectret)(at pin13)
ext
-Z
=10KΩ//8.5nF(internalimpedance)
int
-Z
=10.65 •Z4(at pin 3; see paragr. 2.2)
out
Z
( long )⁄⁄Z
line
Z
( short ) ⁄⁄Z
lin e
⁄⁄Z
⁄⁄Z
int
int
⁄⁄Z
⁄⁄Z
out
out
ext
Z
out
ext
Z
out
- Zline (short) and (long) are the impedances of
the line at minimum and naximum line lenght
-R5 =5.1KΩ±1% (typically)
3.3AC Impedance
The total AC impedance of the circuit to the line
is:
ZAC = Zout//Zint//Zext (ZALS,ZALL>>ZAC)
V20
V16
=(G
− 6dB ) •
r
ZRS
ZRS + ZALS
for shortlines
ZALL and ZALS define the sidetone compensation of the circuit.
Figure6
3.4 Receive Mute (and confidencelevel)
When the receive channel is muted (Vpin 14 >
2.7V)the receive gain is reducedof 60dBmin i m um.
8/15
Page 9
TEA7063
In this condition an internal connection is activated from line DTMF output (pin 16) to Receive
Output(pin 20) with an attenuationGRS = 38.5dB
to provide acoustic feedback of the DTMF emission.
4. A.G.C ANDSIDETONE PROGRAMMING
4.1 ProgrammableControls
AGCand sidetone attackand disonnectpoints(or
currents) are programmable externally through
two independents pins, I-start (pin 9) and I-slope
(pin 15).
4.2 I-Start(pin9)
An external resistor RLL connected between I-
start (pin 9) and Microprocessor Supply (pin 19)
controls the attack point of AGC and ZAL (antisidetoneZ).
ILL is the line current at which the control starts.
Formulasfor ILL and RLL with R9 =100K are:
2880
ILL =
RLL =
4.3 I-Slope (pin 15)
An external resistor RLS connected between
I-slope (pin 15) and Microprocessor Supply (pin
19) controls the disconnected point of AGC and
+ 11mA
RLL
2880
( ILL − 11mA
)
ZAS (antisidetone Z). ILS is the line current at
which the control stops. Formulas for ILS and
RLS with R9 = 100K are:
4680
ILS =
RLS =
4.4 A.G.C. OFF (pin 9 and 15)
Programming ILL and ILS respectively higher
than 70mA and 450mA is forcing the IC in AGC
OFFCondition.
Suggestedexternal componentsare:
RLL = 51KΩ andRLS = 10KΩ
In this case sending, receiving gain and sidetone
compensationare independent of the line lenght.
Pins1 and 2 can be connected to each other saving 5 passive external componentsat pin2.
4.5 Secret Function for Private (pin 14)
The two separate thresholds for sending and Re-
ceiving Mute (pin 14) allow ”Secret Function”
(only microphone muted).
Pin14 can be set:
a) between 0.25Vand 0.8Vfor speechmode,
b) between 1.6V and 2.1V for ”secret” mode (mi-
crophonemuted),
c) between2.7V and 3.3Vfor ”all muted” mode
+ ILL;
RLS
4680
( ILS− ILL
)
Figure7
9/15
Page 10
TEA7063
5. MICROPROCESSOR INTERFACE
5.1 MicroprocessorSupply (pin 19)
At ”off-hook” the first priority of the circuit is to
make some current available at the Microprocessor Supply (pin 19) to charge quickly the external
capacitorC2.
This charging current is I
T-charge of about 10ms is necessary, with C2 =
47/µF. to charge pin 19 at the specified value of
3.3V typical at I
T-charge=
3.3V • C2
0.6 • I
LINE
= 25mA:
LINE
Figure 8
=0.6 •I
cpm
typically
LINE
= 3.3V in normal operation and current in-
V
mp
creases linearly from 0.5mA min, at I
to1.5mA, at I
highervaluesof I
= 25mA, remaining stable for
LINE
. (with R9 = 100K)
LINE
LINE
= 6mA,
In general:
130Volt
I
=
mp
11Volt
I
=
mp
+ 0.3mA at IL>25mA
R9
+ 0.3mA at IL> 6mA
R9
A zener of 3.9V typical is generally suggested to
6. CURRENT SOURCEFORSPEAKERPHONE
6.1 Current Source (pin 12)
Most of the DC current available from the line is
deliveredby the speechcircuit at the outputI
source
(pin 12) through an internalcurrent generator.
Typical values of this current, l
with R9 = 100K,
LS
are:
I
LS
I
LS
(ex: I
=(0.3 •I
=(0.9 •I
LINE
) forI
LINE
-10mA)for I
LINE
LINE
LINE
=16mA then ILS= 5mA
< 16.5mA
>16.5mA
Figure9
= 30mA then ILS= 17mA
I
LINE
I
= 60mA then ILS= 44mA).
LINE
The voltage level at pin 12 mustbe defined by an
external regulator (i.e.: zener) and, if necessary,
filtered with a capacitor(47 to 220µF).
In case V
(at pin 16) approaches voltage at
LINE
pin 12, then the internal current source switches
off and its DC current is shunt to ground through
and internal complementary generator, thus
avoiding any negative effect on the AC and DC
impedancesof the telephonesetapplication.
10/15
Page 11
7. INTERNAL DESCRIPTION OF CURRENT
MANAGEMENT
7.1 Internal PowerSupplyManagement
R9 fixes the linepower supply management.
R9 fixes the valuesof: I
ear,Iup,Iref
and ILS.
A current line information is used to modifie the
values of I
ear,Iup,Iref
and ILS between a minimum
and amaximum values.
On Fig10:
The transmit outputstage is representedby a current source (I
voltageon V
The other internal stages connected to V
). The Itrvalue depends of the DC
tr
(pin 16)and R
LINE
ZAC
value.
LINE
(pin
16) are represented by a constant 1.3mA current
source.
7.2 DCCharacteristics(internal)
The DC characteristicisequals to:
V
(pin 16) = VC(pin17) + R6 •I
LINE
int
Iint is the sum of all the current sources connectedon VC (pin 17):
[I
+ Vpin17 / (r7+ r8)]
p+Iref
is the bias internal operational amplifiers
-I
p
powersupply.
=1 /3•(V
-I
ref
=156/R9mA
-I
ref
/ R9);with V
refi
=470mV
refi
The current line information changesIint value;
at low line current (6mA): I
at low line current (IL = ILb): I
=4V/R9+60µA
int
=8V / R9 + 60µA
int
7.3 Microcontroller Supply (internal)
I
= [(p2 / r2) • I
up
+ 0.3] mA = [(p2 / r2) •156 /
ref
R9)+ 0.3] mA
The current line information changesp2/r2 value;
at low line current (6mA): p2 / r2 = 70
at a linecurrent(IL = ILb): p2 / r2 =820
TEA7063
0.1425 • V
=
I
tr
connectedbetweepin3 and the ground)
7.6 LoudspeakerCurrentSource (internal)
The current source for external peripherals has
two slopes:
- First slope; before I
lized at their maximum values: (IL = ILb)
- Second slope; after I
bilizedat their maximum values: (for IL > ILb)
∆ (ILS) = 0.91 • ∆(I
I
ear,Iup,Itr
and I
values between 16 and 26mA, the absolute IL
value depends of R9 value. The line current (ILb)
where I
ear,Iup,Itr,Iint
mum values and where the slope of ILS change
is:
ILb =
I
7.7 Numerical Example
1)R9 =100KΩ; R6 = 25KΩ
♦ DC characteristic=6V for I
I
min (IL = 6mA) = 4 /100K + 60 =100µA
int
min (IL = ILb) = 8 /100K+ 60 = 140µA
I
int
Vpin17= 2.5V ⇒ R6 = 25KΩ ⇒
Vpin16min (IL =6mA) = 2.5 + 25 •100E- 3 = 5V
Vpin16max (IL = ILb) = 2.5 + 25 • 140E - 3 = 6V
♦ CurrentSources
I
min (IL= 6mA) = 0.4mA
up
I
max (IL = ILb) = 1.6mA
up
I
min (IL = 6mA) = 0.3mA
ear
max (IL = ILb) = 4.2mA
I
ear
with R
I
tr
I
tr
=75Ω
Z
min(IL = 6mA) = 2.6mA
max (IL = ILb) = 4.5mA
ILS min (IL = 6mA) = 1.3mA
− 0.517
LINE
R
Z
ear,Iup,Itr
(RZis the resistor
and I
are stabi-
int
ILS = 0.285 • IL
LINE
and I
int
ear,Iup,Itr
are stabilizedat their maximum
int
are stabilized at their maxi-
+ I
+ I
+ I
ear
up
tr
int
+ 1.3
0.715
max:
int
=5V for I
int
min:
are sta-
7.4 Earphone Current Supply (internal)
I
=(p1 / r1) • I
ear
mA= (p1 /r1) •(156/ R9) mA
ref
The current line information changesp1/r1 value;
at low line current (6mA): (p1 / r1)= 200
at a linecurrent(IL = ILb): p1 / r1 =2700
The maximum peak dynamic on the earphone is:
V
pear=Zear•Iear
7.5 Transmit Output Stage(internal)
The output stage bias current depends of the DC
voltageon pin 16 and on R
impedance.
ZAC
♦ ILb
1.6 + 4.2 + 4.5 + 0.14 + 1.3
ILb =
0.715
mA
ILb = 16.5mA
ILS (for IL = ILb) = 0.285•ILb = 4.7mA
♦ at IL = 100mA:
∆(ILS) = 0.91• ∆(IL) =0.91 •(100 - 16.5) = 76mA
ILS = 4.7 + 76 = 80.7mA
2) R9 =56KΩ; R6 = 18KΩ
♦ DC characteristic=6.1V for I
♦ ∆Χ χηαραχτε = 4.8Vfor I
int
int
max:
min:
11/15
Page 12
TEA7063
I
min (IL = 6mA) = 4 /56K + 60 = 130µA
int
I
min (IL = ILb) = 8 /56K + 60 = 200µA
int
Vpin17= 2.5V ⇒ R6 = 18KΩ ⇒
Vpin16m i n(I L= 6mA) =2.5 + 18•130 E- 3 = 4.85V
Vpin16max(IL = ILb)=2.5+ 18 •200E - 3 = 6.1V
♦ CurrentSources
I
min (IL = 6mA) = 0.5mA
up
I
max (IL = ILb) =2.5mA
up
I
min(IL = 6mA)= 0.55mA
ear
I
max (IL =ILb) = 7.5mA
ear
with R
Figure10: Line Power Supply Management
=75Ω
Z
min(IL = 6mA) = 2.35mA
I
tr
I
max (IL = ILb) = 4.5mA
tr
ILS min (IL = 6mA) = 1.17mA
♦ ILb
2.5 + 7.5 + 4.5 + 0.2 + 1.3
ILb =
0.715
mA
ILb = 22.4mA
ILS (for IL = ILb) = 0.285•ILb = 6.4mA
♦ at IL = 100mA:
∆(ILS) = 0.91• ∆(IL) =0.91 •(100 - 22.6) = 64mA
ILS = 6.4 + 64 = 70.4mA
12/15
Page 13
SO20PACKAGE MECHANICAL DATA
TEA7063
DIM.
mm inch
Min. Typ. Max. Min. Typ. Max.
A 2.65 0.104
a1 0.1 0.2 0.004 0.008
a2 2.45 0.096
b 0.35 0.49 0.014 0.019
b1 0.23 0.32 0.009 0.013
C 0.5 0.020
o
c1 45
(typ.)
D 12.6 13.0 0.496 0.510
E 10 10.65 0.394 0.419
e 1.27 0.050
e3 11.43 0.450
F 7.4 7.6 0.291 0.300
L 0.5 1.27 0.020 0.050
M 0.75 0.030
o
S8
(max.)
13/15
Page 14
TEA7063
DIP20 PACKAGEMECHANICAL DATA
DIM
Min. Typ. Max. Min. Typ. Max.
a1 0.254 0.010
B 1.39 1.65 0.055 0.065
b 0.45 0.018
b1 0.25 0.010
D 25.4 1.000
E 8.5 0.335
e 2.54 0.100
e3 22.86 0.900
F 7.1 0.280
i 3.93 0.155
L 3.3 0.130
Z 1.34 0.053
mm inch
14/15
Page 15
TEA7063
Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the
consequences of use of such informationnor for any infringement of patents or other rights of third parties which may result from its use. No
license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied.
SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of SGS-THOMSONMicroelectronics.
1994 SGS-THOMSON Microelectronics - All RightsReserved
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SGS-THOMSON Microelectronics GROUPOF COMPANIES
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