Philips TEA1113T Datasheet

INTEGRATED CIRCUITS

DATA SH EET

TEA1113

Low voltage versatile telephone transmission circuit with dialler interface

Product speciﬁcation Supersedes data of 1996 Feb 08 File under Integrated Circuits, IC03

1997 Mar 27

Philips Semiconductors Product speciﬁcation

Low voltage versatile telephone transmission circuit with dialler interface

FEATURES

• Low DC line voltage; operates down to 1.6 V (excluding polarity guard)

• Voltage regulator with adjustable DC voltage

• Provides a supply for external circuits

• Symmetrical high impedance inputs (64 kΩ) for

dynamic, magnetic or piezo-electric microphones

• Asymmetrical high impedance input (32 kΩ) for electret microphones

• DTMF input with confidence tone MUTE input for pulse or DTMF dialling

•

• Receiving amplifier for dynamic, magnetic or

piezo-electric earpieces

• Dynamic limitation in the transmit direction to prevent distortion of the transmit line and sidetone signals

• AGC line loss compensation for microphone and earpiece amplifiers

• LED on-hook/off-hook status indication

• Microphone mute function available with switch.

APPLICATION

• Line powered telephone sets, cordless telephones, fax

GENERAL DESCRIPTION

The TEA1113 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 1.6 V DC (with reduced performance) to facilitate the use of telephone sets connected in parallel.

A current (proportional to the line current and internally limited to 19.5 mA) is available to drive an LED which indicates the on-hook/off-hook status.

The transmit signal on the line is dynamically limited to prevent distortion at high transmit levels for both the sending line and sidetone signals. The microphone amplifier can be disabled during speech condition by means of a microphone mute function.

All statements and values refer to all versions unless otherwise specified.

TEA1113

machines and answering machines.

QUICK REFERENCE DATA

= 15 mA; VEE=0V; R

line

=25°C; unless otherwise speciﬁed.

amb

SLPE

=20Ω; C

= 470 nF; AGC pin connected to VEE; Z

DLS

= 600 Ω; f = 1 kHz;

line

SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT

line

line current operating range normal operation 11 − 140 mA

with reduced performance 1 − 11 mA

LED(max)

LN(max)(p-p)

maximum supply current available I

=18 mA − 0.6 − mA

line

>76mA − 19.5 − mA

line

DC line voltage 3.7 4.0 4.3 V maximum output voltage swing

3.8 4.65 − V

(peak-to-peak value)

V G

∆G

vtrx

internal current consumption VCC= 3.2 V − 1.3 1.6 mA supply voltage for peripherals Ip= 0 mA 2.8 3.2 − V typical voltage gain range

microphone amplifier V receiving amplifier V

gain control range for microphone and

= 2 mV (RMS) 38.8 − 51.8 dB

MIC

= 4 mV (RMS) 19.3 − 31.3 dB

=85mA − 5.8 − dB

line

receiving amplifiers with respect to I

=15mA

line

∆G

vtxm

microphone ampliﬁer gain reduction − 80 − dB

1997 Mar 27 2

Philips Semiconductors Product speciﬁcation

Low voltage versatile telephone transmission circuit with dialler interface

ORDERING INFORMATION

TYPE

NUMBER

TEA1113 DIP16 TEA1113T SO16

BLOCK DIAGRAM

handbook, full pagewidth

NAME DESCRIPTION VERSION

plastic dual in-line package; 16 leads (300 mil) plastic small outline package; 16 leads; body width 3.9 mm

V− I

PACKAGE

GAR

15 14 8

MUTE

TEA1113

SOT38-4

SOT109-1

DTMF

MIC+

MIC−

DLS/MMUTE

V− I

ATT.

DYNAMIC

LIMITER

V− I

AGC

CIRCUIT

REFERENCE

LOW VOLTAGE

CIRCUIT

CURRENT

GAS

REG

TEA1113

LED

DRIVER

231013

AGC

LED

MBG018

SLPE

Fig.1 Block diagram.

1997 Mar 27 3

Philips Semiconductors Product speciﬁcation

Low voltage versatile telephone transmission circuit with dialler interface

PINNING

SYMBOL PIN DESCRIPTION

LN 1 positive line terminal SLPE 2 slope (DC resistance) adjustment I

LED

REG 4 line voltage regulator decoupling GAS 5 sending gain adjustment DLS/

MMUTE DTMF 7 dual-tone multi-frequency input MUTE 8 mute input to select speech or

IR 9 receiving ampliﬁer input AGC 10 automatic gain control - line loss

MIC− 11 inverting microphone ampliﬁer

MIC+ 12 non-inverting microphone ampliﬁer

QR 14 receiving ampliﬁer output GAR 15 receive gain adjustment V

3 available output current to drive an

LED

6 dynamic limiter timing adjustment

and microphone mute input

dialling mode (active LOW)

compensation

input

13 negative line terminal

16 supply voltage for speech circuit

and peripherals

handbook, halfpage

DLS/MMUTE

1 2

SLPE

LED

REG

GAS

DTMF MUTE

5 6 7 8

TEA1113

MBG015

Fig.2 Pin configuration.

GAR

MIC+

MIC−

AGC

TEA1113

FUNCTIONAL DESCRIPTION

All data given in this chapter are typical values, except when otherwise specified.

Supply (pins LN, SLPE, V

and REG)

The supply for the TEA1113 and its peripherals is obtained from the telephone line.

The ICs generate a stabilized reference voltage (V

ref

) between pins LN and SLPE. This reference voltage is equal to 3.7 V, is temperature compensated and can be adjusted by means of an external resistor (RVA). It can be increased by connecting the RVA resistor between pins REG and SLPE, or decreased by connecting the R

resistor between pins REG and LN. The voltage at pin REG is used by the internal regulator to generate the stabilized reference voltage and is decoupled by a capacitor (C

) which is connected to VEE. This

REG

capacitor, converted into an equivalent inductance (see Section “Set impedance”), realizes the set impedance conversion from its DC value (R

) to its AC value

SLPE

1997 Mar 27 4

in the audio-frequency range). The voltage at pin

SLPE is proportional to the line current. Figure 3 illustrates the supply configuration.

The IC regulates the line voltage at the pin LN, and it can be calculated as follows:

V I

SLPEIlineICC

line

refRSLPEISLPE

– Ip– I∗– I

: line current

×+=

I+

LED

ICC: current consumption of the IC Ip: supply current for peripheral circuits I*: current consumed between LN and V I

: supply current for the LED component

LED

Ish: the excess line current shunted to SLPE (and VEE) via LN.

Philips Semiconductors Product speciﬁcation

Low voltage versatile telephone

TEA1113

transmission circuit with dialler interface

The preferred value for R microphone and DTMF gains, the LED supply current characteristic, the gain control characteristics, the sidetone level and the maximum output swing on the line.

line

exch

handbook, full pagewidth

is 20 Ω. Changing R

SLPE

LED

TEA1113

LED

DRIVER

LED

SLPE

will affect more than the DC characteristics; it also influences the

SLPE

619 Ω

from preamp

SLPE

20 Ω

REG

4.7 µF

VCC

100 µF

MBG019

peripheral

circuits

(1) RVA between REG and SLPE. (2) No RVA. (3) RVA between REG and LN.

5.5

handbook, halfpage

ref

(V)

4.5

3.5

2.5

Fig.3 Supply configuration.

(1)

(2)

(3)

RVA (Ω)

MGD188

Fig.4 Reference voltage adjustment by a RVA resistor.

1997 Mar 27 5

Philips Semiconductors Product speciﬁcation

Low voltage versatile telephone transmission circuit with dialler interface

The internal circuitry of the TEA1113 is supplied from pin VCC. This voltage supply is derived from the line voltage by means of a resistor (RCC) and must be decoupled by a capacitor C supply peripheral circuits such as dialling or control circuits. The VCC voltage depends on the current consumed by the IC and the peripheral circuits as shown by the formula (see also Figs 5 and 6). R impedance of the voltage supply point, and I current consumed by the output stage of the earpiece amplifier.

CCO

CCORCCintIpIrec

VLNR

×–=

CCICC

The DC line current flowing into the set is determined by the exchange supply voltage (V resistance (R (R

) and the reference voltage (V

line

), the DC resistance of the telephone line

exch

below 8 mA, the internal reference voltage (generating V

) is automatically adjusted to a lower value. This means

ref

that more sets can operate in parallel with DC line voltages (excluding the polarity guard) down to an absolute minimum voltage of 1.6 V. At currents below 8 mA, the circuit has limited sending and receiving levels. This is called the low voltage area.

. It may also be used to

VCC

is the internal

CCint

rec

–()×–=

), the feeding bridge

exch

). With line currents

ref

is the

TEA1113

Set impedance

In the audio frequency range, the dynamic impedance is mainly determined by the RCC resistor. The equivalent impedance of the circuits is illustrated in Fig.7.

LED supply (pin I

The TEA1113 gives an on-hook/off-hook status indication. This is achieved by a current made available to drive an LED connected between pins I voltage area, which corresponds to low line current conditions, no current is available for this LED. For line currents higher than a threshold current, the I increases proportionally to the line current (with a ratio of one third).The I (see Fig.8).

For 17 mA < I

LED

line

17–

line

---------------------3

This LED driver is referenced to SLPE. Consequently, all the I

supply current will flow through the R

LED

The AGC characteristics are not disturbed (see Fig.3 for the supply configuration).

Microphone ampliﬁer (pins MIC+, MIC− and GAS)

)

LED

and LN. In the low

LED

current is internally limited to 19.5 mA

LED

< 77 mA:

SLPE

current

resistor.

handbook, halfpage

CCO

Fig.5 VCC voltage supply for peripherals.

CCintVCC

rec

PERIPHERAL

CIRCUIT

MBE792

The TEA1113 has symmetrical microphone inputs. The input impedance between pins MIC+ and MIC− is 64 kΩ (2 × 32 kΩ). The voltage gain from pins MIC+/MIC− to pin LN is set to 51.8 dB (typ). The gain can be decreased by connecting an external resistor R

GAS

between pins GAS and REG. The adjustment range is 13 dB. A capacitor C

connected between pins GAS

GAS

and REG can be used to provide a first-order low-pass filter. The cut-off frequency corresponds to the time constant C

GAS

× (R

GASint

// R

GAS

). R

is the internal

GASint

resistor which sets the gain with a typical value of 69 kΩ. Automatic gain control is provided on this amplifier for line

loss compensation.

Dynamic limiter and microphone mute (pin DLS/

MMUTE)

The dynamic limiter only acts on the microphone channel, this is to prevent clipping of the line signal. To prevent distortion, the microphone gain is rapidly reduced when peaks on the line signal exceed an internally determined threshold level or when the current in the transmit output stage is insufficient. The time in which the gain reduction is realized is very short (attack time). The microphone channel stays in the reduced gain condition until the peaks

1997 Mar 27 6

+ 14 hidden pages