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FEATURES:
SPEECH
DC LINE CURRENT RANGE FROM 6 TO
110mA
Tx AND Rx GAIN EXTERNALLY ADJUSTABLE
AGC IN Tx AND Rx EXTERNALLY PROGRAMMABLE
AGC DISABLEABLE THROUGH MICROCONTROLLER BUS
SINGLE/DOUBLE SIDETONE NETWORK
SOFTWAR E PROGRAMMABLE
SOFTCLIPPING ON Tx CHANNEL
SQUELCH TO REDUCE Tx NOISE ENVI-
ROMENT AND TO IMPROVE HOWLING IMMUNITY IN LOUDHEARING MODE
RECEIVING AMPLIFIER FOR PIEZO OR
ELECTRO DYNAMIC TRANS DUCE RS
+6dB MODE ON Rx CHANNEL (SELECTABLE
THROUGH MICROCONTROLLER BUS)
–6dB MODE ON Tx CHANNEL (SELECTABLE
THROUGH MICROCONTROLLER BUS)
FREQUENCY GENERATOR FOR WAITING
MELODY
ERROR BEEP GENERATOR
HOLD LINE CURRENT DETECTOR FOR
TRANSFER/ AUTO RELEASE
TEA7091
TELEPHONE ANALOG FRONT END
PRODUCT PREVIEW
PLCC44
PQFP44
PLY TO FEED THE LOUDSP EAKER AMPLIFIER DURING RING MODE
DIGITAL VOLUME CONTROL (8 STEPS OF
4dB EACH) THROUGH MICROCONTROLLER BUS
RING FREQUENCY GENERATOR PROGRAMMED THROUGH MICROCONTROLLER BUS
GROUP LISTENING / ON-HOOK DIALING
ANTI HOWLING WITH ACOUSTIC FEEDBACK SYSTEM COUPLED WITH SQUELCH
DIGITAL VOLUME CONTROL (8 STEPS OF
4dB EACH) THROUGH MICROCONTROLLER BUS
ANTIL ARSEN A TTENUAT ION ( 4 DIF FEREN T
LEVELS) PROGRAMMABLE THROUGH MICROCONT RO LLER BUS
HANDSFRE E INTERF ACE
PIN AND SOFTWARE FACILITY FOR EASY
INTERCONNECTION WITH HANDSFREE
CONTRO L LE R IC.
RING ON LOUDSPEAKER
EMBEDDED SWITCH MODE POWER SUP-
September 1993
This is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice.
DIALLING
DTMF GENERATOR (CONTROLLED BY
MCU BUS)
DC MASK VALUE DURING MAKE PERIOD
PROGRAMMABLE THROUGH MICROCONTROLLER BUS
MICROCO NTR OL LER INTE RF ACE
STABILIZED VOLTAGE FOR MICROCONTROLLER
2 WIRE SERIAL BUS
RING INDICATOR
POWER-ON SIGNAL
RESET SIGNAL
LINE CURRENT VARIATION INDICATO R
SELF BIASED LOUDSPEAKER AMPLIFIER FOR
ANSWER ING MA CHIN E
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TEA7091
DESCRIP TION
The TEA7091 is a Telephone set Analog Front
End (TAFE) interface intended for use in conjunction with a microcontroller.
In this configuration the TEA7091 provides a
worldwide mid-range telephone set with loudhearing on board and melody ringer on loudspeaker.
Repertory dialer (memory on MCU) and various
features (HOLD, Tone/Pulse, Flash, MUTE, adjustable Ringer and Loudhearing levels..) are programmable by MCU.
Also high-range telephone set can be built around
TEA7091 by adding Handsfree controller
(TEA7540), E lectronic Hook Switch and upgraded
PINS CON NE CT ION (T op views)
SWP
RSU
RCO
GNDP
LSOUT
VLS
VMC
VREFL
LSIN
LSSOF
DTMF
VRMC
OSC
RI/VI
RESET
N.C.
7
8
9
VL
10
11
12
13
14
15
16
17
VZP
123564
PLCC44
2322211918 20 28272624 25
GREC
EAR-
EAR+
ISL
40414244 43
39
ILL
38
GNDA
37
SLP
36
VS
35
IREF
34
SOFTL
33
TSOFT
32
VCC
31
VREF
30
MIC2
29
MIC1
MCU (ST family) with LCD driver.
The concept using TAFE + Microcontroller is
called BICHIP approach.
The benefits of this concept are:
– Saving of external components.
– Easy upgrade of the features (extra memories,
LCD driver, Answering machine or Cordless interface..) through microcont roller.
– Replacement of configuration switches (PABX
/Public, Tone/Pulse...) by EEPROM set tings.
This also induces reliability and cost improvement.
LSOUT
GNDP
N.C.
RCO
SWP
RSU
VZP
GREC
EAR-
EAR+
ISL
44 43 42 41 3940 38 37 36 35 34
VLS
VMC
VREFL
LSIN
LSSOF
DTMF
VRMC
OSC.
RI/VI
RESET
1
2
3
VL
4
5
6
7
8
9
10
12 13 14 15 16
PQFP44
171118 19 20 21 22
ILL
33
GNDA
32
SLP
31
VS
30
IREF
29
SOFTL
28
TSOFT
27
VCC
26
VREF
25
MIC2
24
MIC1
23
PON
CLK
DATA
SNSL
SNLL
ACFSL
ACFFI
RECIN
REOUT
GTR
HFIN
D93TL010
PON
CLK
DATA
SNSL
SNLL
ACFSL
ACFFI
RECIN
REOUT
GTR
ABSOLUTE MAXIMUM RATINGS
Symbol Parameter Value Unit
Operating Temperature – 25 to +70 °C
Storage Temperature – 55 to +150 °C
Supply Voltage (pin 3) 12 V
Supply Current 150 mA
CMOS part supply (Pin 8) 6 V
Junction Temperature – 25 to +150 °C
2/7
V
T
op
T
stg
V
LM
I
LM
REGM
T
j
HFIN
D93TL011
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PIN DESCRIPTIONS
TEA7091
PQFP44
o
N
Pins
1 7 VLS Loudspeaker power supply.
2 8 VMC Unregulated microcontroller supply.
3 9 VL Line voltage.
4 10 VREFL Loudspeaker reference voltage.
5 11 LSIN Loudspeaker input.
6 12 LSSOF Loudspeaker softclipping time constatnt.
7 13 DTMF DTMF filter.
8 14 VRMC Stabilized microcontroller supply.
9 15 OSC Oscillator input.
10 16 RI/VI Ring indicator / Line current variation indicator.
11 17 RESET Microcontroller reset.
12 18 PON Power on output.
13 19 CLK Clock data input.
14 20 DATA Data Input.
15 21 SNSL Short line sidetone input.
16 22 SNLL Long line sidetone input.
17 23 ACFSL Anti-acoustic feedback and squelch peak voltage.
18 24 ACFFI Anti-acoustic feedback and squelch filter.
19 25 RECIN Receiving Input.
20 26 REOUT Receive output.
21 27 GTR Transmit gain adjustment.
22 28 HFIN Handsfree microphone input.
23 29 MIC1 Microphone input.
24 30 MIC2 Microphone input.
25 31 VREF Transmit and receive reference voltage (VCC/2).
26 32 VCC Transmit and receive power supply.
27 33 TSOFT Transmit soft-clipping time constant.
28 34 SOFTL Maximum AC signal (Softclipping threshold).
29 35 IREF Internal reference current.
30 36 VS Shunt regulator capacitor.
31 37 SLP DC mask slope.
32 38 GNDA Analog Ground (signal).
33 39 ILL Line current regulation start up.
34 40 ISL Line current regulation stop.
35 41 EAR+ Positive earphone output.
36 42 EAR– Negative earphone output.
37 43 GREC Receive gain adjustment.
38 44 VZP Switch mode power supply internal zener.
39 1 SWP Switch mode power supply output.
40 2 RSU Ring start up level.
41 3 RCO Ring capacitor optimization (output power).
42 4 N.C. Not Connected.
43 5 GNDP Power Ground.
44 6 LSOUT Loudspeaker Output.
PLCC44
No Pins
Names Functions
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