INTEGRATED CIRCUITS
DATA SHEET
TEA1111A
Speech circuit with dialler interface,
regulated supply and earpiece
volume control
Product specification
Supersedes data of 1999 Nov 22
File under Integrated Circuits, IC03
2000 Feb 18
Philips Semiconductors
Product specification
Speech circuit with dialler interface, regulated
supply and earpiece volume control
FEATURES
•
Low DC line voltage; operates down to 1.5 V (excluding
voltage drop across external polarity guard)
•
Line voltage regulator with adjustable DC voltage
•
3.25 V regulated strong supply point for peripheral
circuits compatible with:
– Speech mode
– Ringer mode
– Trickle mode.
•
Transmit stage with:
– Microphone amplifier with symmetrical high
impedance inputs
– DTMF amplifier with confidence tone on earpiece.
•
Receive stage with:
– Earpiece amplifier with adjustable gain and volume
control.
•
MUTE input for pulse or DTMF dialling
•
AGC line loss compensation for microphone and
earpiece
•
LED control output.
APPLICATIONS
TEA1111A
•
Line powered telephone sets with LCD module
•
Cordless telephones
•
Fax machines
•
Answering machines.
GENERAL DESCRIPTION
The TEA1111A is a bipolar integrated circuit that performs
all speech and line interface functions required in fully
electronic telephone sets. It performs electronic switching
between speech and dialling. The IC operates at a line
voltage down to 1.5 V DC (with reduced performance) to
facilitate the use of telephone sets connected in parallel.
When the line current is high enough, a fixed amount of
current is derived from the LN pin in order to create a
strong supply point at pin V
DD
. The voltage at pin V
DD
is
regulated to 3.25 V to supply peripherals such as dialler,
LCD module and microcontroller.
QUICK REFERENCE DATA
I
line
= 15 mA; V
EE
= 0 V; V
VCI
= 0 V; R
SLPE
= 20
Ω;
AGC pin connected to V
EE
; Z
line
= 600
Ω;
f = 1 kHz; measured
according to test circuits given in Figs 15, 16 and 17; T
amb
= 25
°C;
T
j
= 25
°C
for TEA1111AUH; unless otherwise
specified.
SYMBOL
I
line
PARAMETER
line current operating range
CONDITIONS
normal operation
with reduced
performance
V
LN
I
CC
V
CC
V
DD
DC line voltage
internal current consumption
supply voltage for internal circuitry (unregulated)
regulated supply voltage for peripherals
speech mode
ringer mode
I
DD
G
v(TX)
G
v(QR)
∆G
v(QR)
∆G
v(trx)
available supply current for peripherals
typical voltage gain for microphone amplifier
typical voltage gain for earpiece amplifier
volume control range for earpiece amplifier
gain control range for microphone and earpiece
amplifiers with respect to I
line
= 15 mA
I
line
= 85 mA
MUTE = LOW
V
MIC
= 4 mV (RMS)
V
IR
= 4 mV (RMS)
I
DD
=
−3
mA
I
DD
= 75 mA
2.95
3.0
−
43.2
26.4
0
−
−
3.25
3.3
−
44.2
27.4
14.5
6.0
80
3.55
3.6
−3
45.2
28.4
−
−
−
V
V
mA
dB
dB
dB
dB
dB
V
CC
= 3.3 V
I
P
= 0 mA
MIN.
11
1
3.7
−
−
TYP. MAX. UNIT
−
−
4.0
1.15
3.3
140
11
4.3
1.4
−
mA
mA
V
mA
V
∆G
v(trx)(m)
gain reduction for microphone and earpiece
amplifiers
2000 Feb 18
2
Philips Semiconductors
Product specification
Speech circuit with dialler interface, regulated
supply and earpiece volume control
ORDERING INFORMATION
TYPE
NUMBER
TEA1111AT
TEA1111AUH
BLOCK DIAGRAM
PACKAGE
NAME
SO16
−
bare die; on foil
DESCRIPTION
plastic small outline package; 16 leads; body width 3.9 mm
TEA1111A
VERSION
SOT109-1
−
handbook, full pagewidth
VCI
receive
amplifier
V
I
9
VOLUME
CONTROL
GAR
12
IR
4
11
earpiece
amplifier
QR
MUTE
8
V
I
0.5VCC
CURRENT AND
VOLTAGE
REFERENCE
DTMF
6
ATTENUATOR
16
VDD
V
I
REGULATOR
7
VCC
VDD
MIC+
MIC−
13
14
V
I
1
LN
microphone
amplifier
10
AGC
CIRCUIT
VEE
LOW VOLTAGE
CIRCUIT
AGC
5
TEA1111A
3
REG
LED CONTROL
15
LEDC
2
SLPE
FCA051
Fig.1 Block diagram.
2000 Feb 18
3
Philips Semiconductors
Product specification
Speech circuit with dialler interface, regulated
supply and earpiece volume control
PINNING
PIN
SYMBOL
TEA1111TV
LN
SLPE
REG
IR
AGC
DTMF
V
DD
MUTE
n.c.
VCI
V
EE
QR
GAR
MIC+
MIC−
LEDC
V
CC
1
2
3
4
5
6
7
8
−
9
10
11
12
13
14
15
16
TEA1111AUH
1
2
3
4
5
6
7
8
9
10
11, 12
13
14
15
16
17
18
positive line terminal
slope (DC resistance) adjustment
line voltage regulator decoupling
receive amplifier input
automatic gain control/ line loss compensation
dual-tone multi-frequency input
regulated supply for peripherals
PAD
DESCRIPTION
TEA1111A
mute input to select speech or dialling mode (active LOW)
not connected
volume control input
negative line terminal
earpiece amplifier output
earpiece amplifier gain adjustment
non-inverting microphone amplifier input
inverting microphone amplifier input
LED control output
supply voltage for internal circuit
handbook, halfpage
LN 1
SLPE 2
REG 3
IR 4
16 VCC
15 LEDC
14 MIC−
13 MIC+
TEA1111A
AGC 5
DTMF 6
VDD 7
MUTE 8
FCA052
12 GAR
11 QR
10 VEE
9
VCI
Fig.2 Pin configuration.
2000 Feb 18
4
Philips Semiconductors
Product specification
Speech circuit with dialler interface, regulated
supply and earpiece volume control
FUNCTIONAL DESCRIPTION
All data given in this chapter concerns typical values,
except when otherwise specified.
Supply (pins LN, SLPE, REG, V
CC
and V
DD
)
The supply for the TEA1111A and its peripherals is
obtained from the telephone line (see Fig.3).
T
HE LINE INTERFACE
(
PINS
LN, SLPE
AND
REG)
The IC generates a stabilized reference voltage (V
ref
)
across pins LN and SLPE. V
ref
is temperature
compensated and can be adjusted by using an external
resistor (R
VA
). V
ref
equals 3.8 V and can be increased by
connecting R
VA
between pins REG and SLPE or
decreased by connecting R
VA
between pins REG and LN.
The voltage at pin REG is used by the internal regulator to
generate V
ref
and is decoupled by C
REG
, which is
connected to V
EE
. This capacitor, converted to an
equivalent inductance, (see Section “Set impedance”)
determines the set impedance conversion from its DC
value (R
SLPE
) to its AC value (R
CC
in the audio-frequency
range). The voltage at pin SLPE is proportional to the line
current.
The voltage at pin LN is:
V
LN
= V
ref
+ R
SLPE
×
I
SLPE
I
SLPE
= I
line
−
I
CC
−
I
P
−
I
SUP
−
I
LEDC
where:
I
line
= line current
I
CC
= current consumption of the IC
I
P
= supply current for external circuits
I
SUP
= current consumed between LN and V
EE
by the
V
DD
regulator
I
LEDC
= supply current for external LED circuitry.
TEA1111A
The preferred value for R
SLPE
is 20
Ω.
Changing R
SLPE
will
affect more than the DC characteristics; it also influences
the microphone and DTMF gains, the gain control
characteristics, the sidetone level and the maximum
output swing on the line.
The DC line current flowing into the set is determined by
the exchange supply voltage (V
EXCH
), the feeding bridge
resistance (R
EXCH
), the DC resistance of the telephone
line (R
line
) and the reference voltage (V
ref
). With line
currents below I
low
(9 mA), the internal reference voltage
(generating V
ref
) is automatically adjusted to a lower value.
This means that several sets can operate in parallel with
DC line voltages (excluding the polarity guard) down to an
absolute minimum voltage of 1.5 V. At line currents below
I
low
, the circuit has limited sending and receiving levels.
This is called the low voltage area.
T
HE INTERNAL SUPPLY POINT
(
PIN
V
CC
)
The internal circuitry of the TEA1111A is supplied from
pin V
CC
. This voltage supply is derived from the line
voltage by means of a resistor (R
CC
) and must be
decoupled by a capacitor C
VCC
. It may also be used to
supply some external circuits.
The V
CC
voltage (see also Figs 4 and 5) depends on the
current consumed by the IC and the peripheral circuits as:
V
CC0
= V
LN
−
R
CC
×
I
CC
V
CC
= V
CC0
−
R
CC
×
(I
P
+ I
rec
)
Where I
rec
is the current consumed by the output stage of
the earpiece amplifier.
2000 Feb 18
5