TEA1506AP Philips Semiconductors, TEA1506AP Datasheet - Page 11

• Manufacturer Part Number: TEA1506AP
• Description: GreenChip SMPS control IC
• Manufacturer: Philips Semiconductors

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DataSheet
Philips Semiconductors
Control pin protection
If pin CTRL is open-circuit or not connected, a fault
condition is assumed and the converter will stop switching.
Operation will recommence as soon as the fault condition
is removed.
Soft start-up
To prevent transformer rattle during hiccup, the
transformer peak current is slowly increased by the soft
start function. This can be achieved by inserting a resistor
and a capacitor between pin I
(see Fig.11). An internal current source charges the
capacitor to V = I
approximately 0.5 V.
The start level and the time constant of the increasing
primary current level can be adjusted externally by
changing the values of R
The charging current I
pin I
pin I
start limiting the current I
current source is completely switched off.
Since the soft start current I
the R
2003 Sep 09
I
4
primary(max)
=
U
GreenChip II SMPS control IC
sense
sense
.com
R
SS
SS
value will not affect the V
is below approximately 0.5 V. If the voltage on
exceeds 0.5 V, the soft start current source will
C
=
SS
V
---------------------------------------------- -
ocp
SS
–
R
R
SS
I
sense
SS
SS
will flow as long as the voltage on
SS
SS
, with a maximum of
. At the V
SS
R
and C
SS
sense
is supplied from pin DRAIN,
CC
SS
and the sense resistor
current during start-up.
.
CC(start)
level, the I
DataSheet4U.com
SS
11
Driver
The driver circuit to the gate of the power MOSFET has a
current sourcing capability of 135 mA typical and a current
sink capability of 560 mA typical. This permits fast turn-on
and turn-off of the power MOSFET for efficient operation.
A low driver source current has been chosen to limit the
Interference (EMI) and also limits the current spikes
across R
handbook, halfpage
V/ t at switch-on. This reduces Electro Magnetic
0.5 V
sense
.
TEA1506P; TEA1506AP;
TEA1506T; TEA1506AT
Fig.11 Soft start.
start-up
V ocp
I SS
5
I sense
R SS
C SS
Product specification
R sense
MGU237