TEA7063 ST Microelectronics, Inc., TEA7063 Datasheet - Page 9

• Manufacturer Part Number: TEA7063
• Description: Speech Circuit With Power Management
• Manufacturer: ST Microelectronics, Inc.

In this condition an internal connection is acti-
vated from line DTMF output (pin 16) to Receive
Output (pin 20) with an attenuation GRS = 38.5dB
to provide acoustic feedback of the DTMF emis-
sion.
4. A.G.C AND SIDETONE PROGRAMMING
4.1 Programmable Controls
AGC and sidetone attack and disonnect points (or
currents) are programmable externally through
two independents pins, I-start (pin 9) and I-slope
(pin 15).
4.2 I-Start (pin 9)
An external resistor RLL connected between I-
start (pin 9) and Microprocessor Supply (pin 19)
controls the attack point of AGC and ZAL (an-
tisidetone Z).
ILL is the line current at which the control starts.
Formulas for ILL and RLL with R9 = 100K are:
4.3 I-Slope (pin 15)
An external resistor RLS connected between
I-slope (pin 15) and Microprocessor Supply (pin
19) controls the disconnected point of AGC and
Figure 7
RLL =
ILL =
2880
RLL
ILL 11mA
2880
11mA
ZAS (antisidetone Z). ILS is the line current at
which the control stops. Formulas for ILS and
RLS with R9 = 100K are:
4.4 A.G.C. OFF (pin 9 and 15)
Programming ILL and ILS respectively higher
than 70mA and 450mA is forcing the IC in AGC
OFF Condition.
Suggested external components are:
RLL = 51K
In this case sending, receiving gain and sidetone
compensation are independent of the line lenght.
Pins 1 and 2 can be connected to each other sav-
ing 5 passive external components at pin 2.
4.5 Secret Function for Private (pin 14)
The two separate thresholds for sending and Re-
ceiving Mute (pin 14) allow ”Secret Function”
(only microphone muted).
Pin 14 can be set:
a) between 0.25V and 0.8V for speech mode,
b) between 1.6V and 2.1V for ”secret” mode (mi-
crophone muted),
c) between 2.7V and 3.3V for ”all muted” mode
and RLS = 10K
RLS =
ILS =
4680
RLS
ILS
4680
ILL
ILL;
TEA7063
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