tda8357j-n2 NXP Semiconductors, tda8357j-n2 Datasheet - Page 10

• Manufacturer Part Number: tda8357j-n2
• Description: Full Bridge Vertical Deflection Output Circuit In Lvdmos
• Manufacturer: NXP Semiconductors

Philips Semiconductors
R
Before calculating the measuring resistor (R
differential input voltage [V
voltage can be measured between pins INA and INB. The
calculation is
Most of the TV signal processors from Philips have a
current output. This current has to be converted by
resistors at the input of the TDA8357J (R
The voltage across these resistors can be calculated. The
differential input voltage is given in the following equation
(refer also to Fig 5):
V
Values for these currents are, for instance
I
Therefore the differential input voltage V
475 A
Supply voltage calculation
Before calculating the minimum required supply voltage,
several specific application parameter values have to be
2002 May 06
i(bias)
i(dif)(p-p)
M
Full bridge vertical deflection output circuit
in LVDMOS
calculation
= 400 A; I
= I
2.2 k
i1(p-p)
PROCESSOR
TV SIGNAL
Fig.5 Differential input voltage.
R
M
I I(bias)
I I(bias)
i1(p-p)
=
R
( 475 A
V
--------------------- -
CV1
0
0
i(dif)(p-p)
I
= I
o(p-p)
i2(p-p)
I i1(p-p)
I i2(p-p)
( I
i(dif)
i2(p-p)
2.2 nF
2.2 nF
] has to be known. This
C7
C6
= 475 A.
2.2 k ) = 2.1 V
)
2.2 k
2.2 k
R CV1
R CV2
R
CV2
INA
INB
i(dif)(p-p)
CV1
MBL528
M
1
2
and R
), the
will be
CV2
).
10
known. These parameters are the required maximum
(peak) deflection coil current I
R
required maximum (peak) deflection coil current should
also include the overscan.
The deflection coil resistance has to be multiplied by a
factor of 1.2 in order to take account of hot conditions.
Chapter “Characteristics” supplies values for the voltage
losses of the vertical output stage. For the first part of the
scan the voltage loss is given by V
part of the scan the voltage loss is given by V
The voltage drop across the deflection coil during scan is
determined by the coil impedance. For the first part of the
scan the inductive contribution and the ohmic contribution
to the total coil voltage drop are of opposite sign, while for
the second part of the scan the inductive part and the
ohmic part have the same sign.
For the vertical frequency the maximum frequency
occurring must be applied to the calculations.
The required power supply voltage V
the scan is given by
The required power supply voltage V
of the scan is given by
The minimum required supply voltage V
highest of the two values V
voltage and component values also has to be taken into
account.
Flyback supply voltage calculation
If the flyback time is known, the required flyback supply
voltage can be calculated by the simplified formula
where
The flyback supply voltage calculated this way is about
5% to 10% higher than required.
V
V
V
x
–
+
coil
P 1
P 2
FB
L
=
L
coil
coil
and L
-------------------------- -
R
=
=
=
coil
I
L
I
coil p p
I
coil peak
2I
coil
2I
coil peak
+
coil
coil peak
coil peak
R
, and the measuring resistance of R
–
M
R
-------------------------- -
1 e
coil
–
R
R
f
f
coil
vert max
vert max
t –
coil
+
FB
R
+
P(1)
+
M
x
R
R
coil(peak)
M
M
and V
+
+
V
V
loss(1)
loss 1
loss 2
P(2)
P
Product specification
, the coil parameters
P
for the second part
for the first part of
TDA8357J
. Spread in supply
. For the second
P
shall be the
loss(2)
M
. The
.