tea1114auh NXP Semiconductors, tea1114auh Datasheet - Page 8

• Manufacturer Part Number: tea1114auh
• Description: Low Voltage Telephone Transmission Circuit With Dialler Interface And Regulated Strong Supply
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Set impedance
In the audio frequency range, the dynamic impedance is
mainly determined by the R
impedance of the circuit is illustrated in Fig.7.
2000 Mar 21
handbook, full pagewidth
handbook, halfpage
Low voltage telephone transmission circuit with
dialler interface and regulated strong supply
L
R
R
Fig.7 Equivalent impedance between LN and V
EQ
P
P
= internal resistance.
= 17.5 k .
V EXCH
= C
R EXCH
REG
R
V EE
SLPE
LN
SLPE
R line
R
P
TEA1114A
.
L EQ
R SLPE
20
V ref
CC
I line
LN
I SUP
I LN
resistor. The equivalent
REG
R P
4.7 F
C REG
SENSE
V CC
R CC
100 F
619
C VCC
MBE788
Fig.6 V
R CC
DD
EE
regulator configuration.
.
SWITCH
V CC
I CC
8
Transmit stage (pins MIC+, MIC and DTMF)
M
The TEA1114A has symmetrical microphone inputs.
The input impedance between pins MIC+ and MIC is
64 k (2
to pin LN is set at 44.2 dB (typically).
Automatic gain control is provided on this amplifier for line
loss compensation.
DTMF
When the DTMF amplifier is enabled, dialling tones may
be sent on line. These tones are also sent to the receive
output RX at a low level (confidence tone).
The TEA1114A has an asymmetrical DTMF input.
The input impedance between DTMF and V
The voltage gain from pin DTMF to pin LN is set at 26 dB.
Automatic gain control has no effect on the DTMF
amplifier.
V DD regulator
ICROPHONE AMPLIFIER
V EE
AMPLIFIER
32 k ). The voltage gain from pins MIC+/MIC
V DD
(
PIN
DTMF)
I DD
(
PINS
peripherals
MIC+
AND
Product specification
C VDD
220 F
TEA1114A
MGK807
MIC )
EE
C VCC
100 F
is 20 k .