1999 Apr 08
9
Philips Semiconductors
Product specification
Speech and loudspeaker amplifier IC with
auxiliary inputs/outputs and analog multiplexer
TEA1097
Fig.5 Main DC voltages as a function of line current.
handbook, full pagewidth
0.07
0.06
6
2
0
0
0.01
voltages
(V)
0.02
0.05
MICS
VDD
VBB
SLPE
LN
Iline (A)
0.04
0.03
4
FCA049
E
XTERNAL SUPPLY
(
PINS
ESI
AND
V
BB
)
The TEA1097 can be supplied by the line as well as by
external power sources (voltage or current sources) that
must be connected to pin ESI.
The IC will choose which supply to use according to the
voltage it can provide. A voltage supply on ESI is efficient
only if its value is greater than the working voltage of the
internal V
BB
voltage stabilizer. Otherwise the IC continues
to be line powered. The current consumed on this source
is at least equal to the internal consumption. It depends on
the voltage difference between the value forced on ESI
and the working voltage of the internal stabilizer.
The current required increases with the voltage difference
to manage. The excess current compared to the internal
consumption becomes then available for other purposes
such as supplying a loudspeaker amplifier. The voltage
source should not exceed 6 V. If the value of the external
voltage source can be lower than the working voltage of
the internal stabilizer, an external diode is required to avoid
reverse current flowing into the external power supply.
In case of current source, the voltage on V
BB
and ESI
depends on the current available. It is internally limited to
6.6 V. The current source should not exceed 140 mA.
V
DD
SUPPLY FOR MICROCONTROLLERS
(
PIN
V
DD
)
The voltage on V
DD
supply point follows the voltage on V
BB
with a difference equal to 250 mV (typ.) and is internally
limited to 3.35 V. This voltage is temperature
compensated. This supply point can provide a current up
to 3 mA (typ.). Its internal consumption stays low (a few
10 nA) as long as V
DD
does not exceed 1.5 V (see Fig.6).
An external voltage can be connected on V
DD
with limited
extra consumption on V
DD
(typically 100
μ
A). This voltage
source should not be lower than 3.5 V and higher than 6 V.
V
BB
and V
DD
can supply external circuits in the limits of
currents provided either from the line or from pin ESI,
taking into account the internal current consumption.