tea1097h NXP Semiconductors, tea1097h Datasheet - Page 11

• Manufacturer Part Number: tea1097h
• Description: Speech And Loudspeaker Amplifier Ic With Auxiliary Inputs/outputs And Analog Multiplexer
• Manufacturer: NXP Semiconductors

Philips Semiconductors
R
The TEA1097 is designed to be activated during the
ringing phase. The loudspeaker amplifier can be used for
the melody signal. The IC must be powered by an external
supply on pin ESI, while applying a HIGH level on the logic
input AUXC and a LOW level on the PD input. Only the
HFRX input and the LSAO output are activated, in order to
limit the current consumption. Some dynamic limiting is
provided to prevent V
2.7 V.
Transmit channels (pins MIC+, MIC , DTMF, TXAUX
and LN)
H
LN)
The TEA1097 has symmetrical microphone inputs.
The input impedance between MIC+ and MIC is 70 k
(typ.). The voltage gain between pins MIC+, MIC and LN
is set to 44.3 dB. Without limitation from the output, the
microphone input stage can accommodate signals up to
18 mV (RMS) at room temperature for 2% of THD.
The microphone inputs are biased at one diode voltage.
Automatic gain control is provided for line loss
compensation.
DTMF
The TEA1097 has an asymmetrical DTMF input. The input
impedance between pin DTMF and GND is 20 k (typ.).
The voltage gain between pins DTMF and LN is set to
25.35 dB. Without limitation from the output, the input
stage can accommodate signals up to 180 mV (RMS) at
room temperature for 2% of THD.
When the DTMF amplifier is enabled, dialling tones may
be sent on the line. These tones can be heard in the
earpiece or in the loudspeaker at a low level. This is called
the confidence tone. The voltage attenuation between pins
DTMF and RECO is typically equal to 16.5 dB.
The DC biasing of this input is 0 V.
The automatic gain control has no effect on these
channels.
1999 Apr 08
INGER MODE
ANDSET MICROPHONE AMPLIFIER
Speech and loudspeaker amplifier IC with
auxiliary inputs/outputs and analog multiplexer
AMPLIFIER
(
PINS
(
PINS
ESI, V
BB
DTMF, LN
from being discharged below
BB
, AUXC
(
AND
PINS
AND
RECO)
MIC+, MIC
PD)
AND
11
A
The TEA1097 has an asymmetrical auxiliary input TXAUX.
The input impedance between pins TXAUX and GND is
20 k (typ.). The voltage gain between pins TXAUX and
LN is set to 12.5 dB. Without limitation from the output, the
input stage can accommodate signals up to 1.2 V (RMS)
at room temperature for 2% of THD. The TXAUX input is
biased at two diodes voltage.
Automatic gain control is provided for line loss
compensation.
M
AND
The voltage gain between the microphone inputs MIC+,
MIC and the output TXOUT is set to 49.8 dB. This
channel gives an image of the signal sent on the line while
speaking in the handset microphone. Using external
circuitry, this signal can be used for several purposes such
as sending dynamic limiting or anti-howling in a listening-in
application. The TXOUT output is biased at two diodes
voltage.
The automatic gain control has no effect on these
channels.
Receive channels (pins IR, RAUX, RECO, GARX and
QR)
RX
The receive amplifier has one input IR which is referred to
the line. The input impedance between pins IR and LN is
20 k (typ.) and the DC biasing between these pins is
equal to one diode voltage. The gain between pins IR
(referenced to LN) and RECO is typically equal to 29.7 dB.
Without limitation from the output, the input stage can
accommodate signals up to 50 mV (RMS) at room
temperature for 2% of THD.
This receive amplifier has a rail-to-rail output RECO, which
is designed for use with high-ohmic (real) loads (larger
than 5 k ). This output is biased at two diodes voltage.
Automatic gain control is provided for line loss
compensation.
UXILIARY
ICROPHONE MONITORING ON
AMPLIFIER
TXOUT)
T
RANSMIT AMPLIFIER
(
PINS
IR
AND
RECO)
TXOUT (
(
PINS
TXAUX
Product specification
PINS
TEA1097
MIC+, MIC
AND
LN)