TEA1098 Philips Semiconductors, TEA1098 Datasheet - Page 8

• Manufacturer Part Number: TEA1098
• Description: Speech and handsfree IC
• Manufacturer: Philips Semiconductors

Philips Semiconductors
The preferred value for R
not only affects the DC characteristics, it also influences
the transmit gains to the line, the gain control
characteristic, the sidetone level, and the maximum output
swing on the line.
Figure 4 shows that the internal circuit is supplied by pin
V
supply point.
The line current through resistor R
voltage stabilizer, and is suitable for supplying a
loudspeaker amplifier or any peripheral IC. Voltage V
3.0 V at line currents below 18 mA and rises linearly to
5.3 V when the line current rises above 45 mA. It is
temperature compensated.
1999 Oct 14
handbook, full pagewidth
BB
Speech and handsfree IC
, which combined with the line interface is a strong
GND
REG
LN
C REG
4.7 F
SLPE
SLPE
is 20 . Changing this value
SLPE
TP1
TN1
R3
R2
is sunk by the V
preamp
Fig.4 Line interface principle.
from
R1
J1
R SLPE
20
BB
BB
is
D1
8
J2
The current switch TR1-TR2 is intended to reduce
distortion of large AC line signals. Current I
to V
V
value, I
Voltage V
resistor between pins REG and SLPE. For large line
currents, this increase can slightly affect some dynamic
performances such as maximum signal level on the line at
2% Total Harmonic Distortion (THD). The external resistor
does not affect the voltage on pin V
main DC voltages.
BB
E1
BB
+ 0.25 V. When the voltage on pin SLPE is below this
via TR1 when the voltage on pin SLPE is above
SLPE
GND
ref
TR1
is shunted to GND via TR2.
can be increased by connecting an external
TN2
TR2
MGM298
E2
GND
BB
Product specification
; see Fig.5 for the
D1
TEA1098
V BB
SLPE
is supplied