ON5250,135 NXP Semiconductors, ON5250,135 Datasheet - Page 11

• Manufacturer Part Number: ON5250,135
• Description: MOSFET RF SOT223 SC-73
• Manufacturer: NXP Semiconductors

Specifications of ON5250,135

• Package / Case: SOT-223 (3 leads + Tab), SC-73, TO-261
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current Rating: -
• Power - Output: -
• Frequency: -
• Gain: -
• Transistor Type: -
• Noise Figure: -
• Current - Test: -
• Voltage - Test: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 934057275135

Philips Semiconductors
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.10). 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
charging current, the R
current level by a maximum of 60 A (typical value).
2002 Aug 23
I
handbook, halfpage
primary(max)
=
GreenChip
sense
sense
R
SS
0.5 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
TM
–
R
Fig.10 Soft start.
start-up
V ocp
R
SS
I
sense
SS
II SMPS control IC
SS
I SS
SS
will flow as long as the voltage on
SS
SS
value will affect the V
, with a maximum of
5
. At the V
R
SS
and C
I sense
SS
sense
is subtracted from pin V
SS
and the sense resistor
R SS
C SS
.
CC(start)
level, the I
R sense
MGU237
CC
charging
SS
CC
11
Driver
The driver circuit to the gate of the power MOSFET has a
current sourcing capability of 170 mA typical and a current
sink capability of 700 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
V/ t at switch-on. This reduces Electro Magnetic
sense
.
TEA1533P; TEA1533AP
Product specification