TEA1112AT NXP Semiconductors, TEA1112AT Datasheet - Page 5

• Manufacturer Part Number: TEA1112AT
• Manufacturer: NXP Semiconductors

Specifications of TEA1112AT

• Max Transmitter Gain: 53dB
• Receiver Gain (max): 32.7dB
• Operating Temp Range: -25C to 75C
• Package Type: SSOP
• Pin Count: 16
• Operating Current: 1.15mA
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Lead Free Status / Rohs Status: Not Compliant

Philips Semiconductors
FUNCTIONAL DESCRIPTION
All data given in this chapter are typical values, except
when otherwise specified.
Supply (pins LN, SLPE, V
The supply for the TEA1112; TEA1112A and their
peripherals is obtained from the telephone line.
The ICs generate a stabilized reference voltage (V
between pins LN and SLPE. This reference voltage is
equal to 3.35 V, is temperature compensated and can be
adjusted by means of an external resistor (R
increased by connecting the R
pins REG and SLPE (see Fig.5), or decreased by
connecting the R
The voltage at pin REG is used by the internal regulator to
generate the stabilized reference voltage and is decoupled
by a capacitor (C
capacitor, converted into an equivalent inductance (see
Section “Set impedance”), realizes the set impedance
conversion from its DC value (R
in the audio-frequency range). The voltage at pin SLPE is
proportional to the line current. Figure 4 illustrates the
supply configuration.
The ICs regulate the line voltage at pin LN, and can be
calculated as follows:
1997 Mar 26
V
I
handbook, full pagewidth
SLPE
LN
Low voltage versatile telephone
transmission circuits with dialler interface
=
=
V
ref
I
line
R exch
+
R line
V exch
I line
R
–
SLPE
I
CC
VA
REG
–
resistor between pins REG and LN.
I LED
) which is connected to V
I
p
I
SLPE
I –
I LED
CC
=
TEA1112A
TEA1112
I
and REG)
VA
LED
SLPE
DRIVER
resistor between
LED
+
I SLPE
) to its AC value (R
I
sh
I sh
SLPE
LN
VA
R SLPE
20
Fig.4 Supply configuration.
EE
). It can be
V d
. This
15.5 k
ref
R p
)
CC
45.5 k
R d
5
R GASint
69 k
Where:
The preferred value for R
affect more than the DC characteristics; it also influences
the microphone and DTMF gains, the LED supply current
characteristic, the gain control characteristics, the
sidetone level and the maximum output swing on the line.
The internal circuitry of the TEA1112; TEA1112A is
supplied from pin V
the line voltage by means of a resistor (R
decoupled by a capacitor C
supply peripheral circuits such as dialling or control
circuits. The V
consumed by the IC and the peripheral circuits as shown
by the formula (see also Figs.6 and 7). R
internal impedance of the voltage supply point, and I
the current consumed by the output stage of the earpiece
amplifier.
619
V
V
R CC
CC
CC0
from pre amp
I
I
I
I* = current consumed between LN and V
I
I
via LN.
line
CC
p
LED
sh
= supply current for peripheral circuits
= the excess line current shunted to SLPE (and V
=
= current consumption of the IC
= line current
=
= supply current for the LED component
V
V
CC0
LN
REG
4.7 F
C REG
I
*
–
–
CC
R
R
CC
CCint
voltage depends on the current
CC
I CC
. This voltage supply is derived from
V CC
I
V EE
CC
TEA1112; TEA1112A
SLPE
I
p
VCC
–
is 20 . Changing R
I
rec
. It may also be used to
Product specification
C VCC
100 F
MBE789
peripheral
CC
CCint
circuits
) and must be
EE
is the
I P
SLPE
rec
will
EE
is
)