TEA7092 ST Microelectronics, Inc., TEA7092 Datasheet - Page 6

• Manufacturer Part Number: TEA7092
• Description: Telephone Analog Front End
• Manufacturer: ST Microelectronics, Inc.

TEA7092
DC CHARACTERISTICS (T
RETURN LOSS (T
TRANSMIT CHARACTERISTICS
The maximum gain Gtl is adjustable between 44
and 56dB versus RGT value
Z
The AGC variation is programmable through two
external resistors connected on Pins ILL and ISL.
ILL is the line current at which the gain is at the
maximum value and ISL is the line current at which
the gain is at the maximum value minus 6dB. For
line current lower than ILL or higher than ISL, the
transmit and receive gains have a constant value.
The following formulas give RLL and RSL values
versus ILL and ISL.
6/24
Between I
V
For line current higher than 20mA the slope is fixed by RSLP : V
(V
(V
Symbol
IN
Symbol
L
I(V
I(V
RLoss
(I
Gtl
V
L
L
RSL
I
I
= internal impedance at Pin V
V
V
-V
-V
LSQ
L
RMC
LS1
MC
MC
) = RS x (40E
L1
L2
LS
LS
)1
)2
)1
)2
20 x log 820 x
ISL
L
Return Loss
Line Voltage in Speech Mode
Line Voltage after Having Sent
0010101 Mask Code
Loudspeaker Amplifier Quiescent
Bias Current
Unstabilized Supply :
- Start up Current
- Unregulated Input Current
Stabilized Microprocessor Supply
I
Loudspeaker Current Supply
= 8mA and I
LS
Drop Voltage
310
5.6mA
-6
amb
+ 0.5E
Parameter
Parameter
= 25°C, see Test 2
and RLL
L
RZ // RL
= 20mA the DC slope is fixed by RS and RSLP :
-3
amb
RGT // 50k
x I
L
= 25°C, see Test 1)
) + RSLP/55 x (I
L
ILL
# 8k .
R3 // Z
310
5.6mA
I
I
I
V
I
I
V
V
I
L
L
L
L
L
L
LS
L AC
LS
IN
= 20mA
= 90mA
= 20mA
= 20 mA, V
= 20mA, I(V
= 20mA, f = 1000Hz
V
V
I
I
I
I
= 4.5V
= 2V
L
L
L
L
RMC
RMC
= 0V
= 20mA
= 90mA
= 20mA
= 90mA
L
- 5.6E
= 2.4V
= 3.75V
RMS
Test Conditions
Test Conditions
LS
Tx Softclipping (see Figure 2)
Figure 2 :
RMC
-3
no connect, V
).
) = -1.8 or 0mA
L
(I
L
) = V
L
Tx Softclipping and Distortion
at I
MC
(20E
L
= 2.4V
= 20mA
-3
) + RSLP/55 x (I
Min.
Min.
4.1
6.6
3.2
10
11
70
20
2
Typ.
Typ.
4.7
7.5
1.6
1.1
2.7
3.5
1.1
1.8
15
13
77
23
L
- 20E
Max.
Max.
5.25
3.75
8.4
2.5
2.2
3.6
1.3
2.3
-3
).
Unit
Unit
mA
mA
mA
mA
mA
dB
V
V
V
V
V
V