TEA7063 ST Microelectronics, Inc., TEA7063 Datasheet - Page 11

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

7. INTERNAL DESCRIPTION OF CURRENT
MANAGEMENT
7.1 Internal Power Supply Management
R9 fixes the line power supply management.
R9 fixes the values of: I
A current line information is used to modifie the
values of I
and a maximum values.
On Fig 10:
The transmit output stage is represented by a cur-
rent source (I
voltage on V
The other internal stages connected to V
16) are represented by a constant 1.3mA current
source.
7.2 DC Characteristics (internal)
The DC characteristic is equals to:
Iint is the sum of all the current sources con-
nected on VC (pin 17):
[I
The current line information changes Iint value;
at low line current (6mA): I
at low line current (IL = ILb): I
7.3 Microcontroller Supply (internal)
I
R9) + 0.3] mA
The current line information changes p2/r2 value;
at low line current (6mA): p2 / r2 = 70
at a line current (IL = ILb): p2 / r2 = 820
7.4 Earphone Current Supply (internal)
I
The current line information changes p1/r1 value;
at low line current (6mA): (p1 / r1) = 200
at a line current (IL = ILb): p1 / r1 = 2700
The maximum peak dynamic on the earphone is:
V
7.5 Transmit Output Stage (internal)
The output stage bias current depends of the DC
voltage on pin 16 and on R
up
ear
p
pear
- I
- I
- I
+ I
= [(p2 / r2) I
= (p1 / r1) I
power supply.
ref
ref
p
ref
= Z
V
= 1 / 3 (V
= 156 / R9 mA
is the bias internal operational amplifiers
LINE
+ Vpin17 / (r7 + r8)]
ear
ear
(pin 16) = V
, I
LINE
I
tr
ear
up
). The I
ref
, I
refi
ref
(pin 16) and R
ref
mA = (p1 / r1) (156 / R9) mA
/ R9); with V
+ 0.3] mA = [(p2 / r2) 156 /
and ILS between a minimum
tr
ear
C
value depends of the DC
, I
(pin 17) + R6 I
int
ZAC
up
= 4V / R9 + 60 A
int
, I
impedance.
ref
=8V / R9 + 60 A
ZAC
refi
and ILS.
= 470mV
value.
LINE
int
(pin
I
connected betwee pin3 and the ground)
7.6 Loudspeaker Current Source (internal)
The current source for external peripherals has
two slopes:
I
values between 16 and 26mA, the absolute IL
value depends of R9 value. The line current (ILb)
where I
mum values and where the slope of ILS change
is:
7.7 Numerical Example
1) R9 = 100K ; R6 = 25K
I
I
Vpin17 = 2.5V
Vpin16 min (IL = 6mA) = 2.5 + 25 100E - 3 = 5V
Vpin16 max (IL = ILb) = 2.5 + 25 140E - 3 = 6V
I
I
I
I
with R
I
I
ILS min (IL = 6mA) = 1.3mA
ILb =
ILb = 16.5mA
ILS (for IL = ILb) = 0.285 ILb = 4.7mA
ILS = 4.7 + 76 = 80.7mA
2) R9 = 56K ; R6 = 18K
tr
ear
int
int
up
up
ear
ear
tr
tr
(ILS) = 0.91
- First slope; before I
- Second slope; after I
=
DC characteristic = 6V for I
Current Sources
min (IL = 6mA) = 2.6mA
max (IL = ILb) = 4.5mA
ILb
at IL = 100mA:
DC characteristic = 6.1V for I
, I
min (IL = 6mA) = 4 /100K + 60 = 100 A
min (IL = ILb) = 8 /100K + 60 = 140 A
min (IL = 6mA) = 0.4mA
max (IL = ILb) = 1.6mA
min (IL = 6mA) = 0.3mA
max (IL = ILb) = 4.2mA
lized at their maximum values: (IL = ILb)
bilized at their maximum values: (for IL > ILb)
0.1425
up
1.6
Z
, I
ear
ILb =
= 75
tr
, I
and I
up
4.2
I
,
V
ear
R
Itr
(ILS) = 0.91
int
LINE
(IL) = 0.91 (100 - 16.5) = 76mA
Z
, I
ILS = 0.285 IL
R6 = 25K
are stabilized at their maximum
0.715
int
4.5
= 5V for I
= 4.8V for I
I
up
are stabilized at their maxi-
ear
0.517
ear
0.715
, I
0.14
, I
I
up
tr
up
, I
int
int
(R
, I
(I
tr
int
min:
int
Z
LINE
I
max:
tr
and I
int
min:
is the resistor
max:
and I
1.3
int
mA
1.3
TEA7063
int
are stabi-
are sta-
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