tda8358j-n2 NXP Semiconductors, tda8358j-n2 Datasheet - Page 5

• Manufacturer Part Number: tda8358j-n2
• Description: Full Bridge Vertical Deflection Output Circuit In Lvdmos With East-west Amplifier
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Guard circuit
A guard circuit with output pin GUARD is provided.
The guard circuit generates a HIGH-level during the
flyback period. The guard circuit is also activated for one
of the following conditions:
The guard signal can be used for blanking the picture tube
and signalling fault conditions. The vertical
synchronization pulses of the guard signal can be used by
an On Screen Display (OSD) microcontroller.
Damping resistor compensation
HF loop stability is achieved by connecting a damping
resistor R
current values in R
significantly different. Both the resistor current and the
deflection coil current flow into measuring resistor R
resulting in a too low deflection coil current at the start of
the scan.
The difference in the damping resistor current values
during scan and flyback have to be externally
compensated in order to achieve a short settling time.
2002 Sep 25
During thermal protection (T
During an open-loop condition.
Full bridge vertical deflection output circuit
in LVDMOS with east-west amplifier
D1
(see Fig.4) across the deflection coil. The
D1
during scan and flyback are
j
170 C)
M
,
5
For that purpose a compensation resistor R
connected between pins OUTA and COMP. The value of
R
where:
East-west amplifier
The east-west amplifier is current driven. The output can
only sink currents of the diode modulator circuit.
A feedback resistor (see Fig.4) has to be connected
between the input and output of the inverting east-west
amplifier in order to convert the east-west correction input
current into an output voltage. The output voltage of the
east-west circuit at pin OUTEW is given by:
V
The maximum output voltage is V
maximum output current of the circuit is I
R
OUTEW
CMP
CMP
R
V
at flyback.
loss(FB)
coil
is calculated by:
is the coil resistance
=
-------------------------------------------------------------------------------------------------------------
I
V
is the voltage loss between pins V
V
INEW
FB
FB
–
–
V
V
R
loss FB
loss FB
EWF
+ V
–
–
INEW
V
I
coil peak
P
o(max)
R
D1
Product specification
TDA8358J
= 68 V, while the
R
o(max)
R
coil
S
CMP
FB
+
300
and OUTA
= 750 mA.
R
is
M