SMPS PRIMARY I.C.
鈩?/div>
10
1
FEATURE
s
ADJUSTABLE SWITCHING FREQUENCY UP
TO 200KHZ
s
CURRENT MODE CONTROL
s
SOFT START AND SHUT DOWN CONTROL
s
AUTOMATIC BURST MODE OPERATION IN
STAND-BY CONDITION ABLE TO MEET
鈥滲LUE ANGEL鈥?NORM (1W TOTAL POWER
CONSUMPTION)
s
INTERNALLY TRIMMED ZENER
REFERENCE
s
UNDERVOLTAGE LOCK-OUT WITH
HYSTERESIS
s
INTEGRATED START-UP SUPPLY
s
AVALANCHE RUGGED
s
OVERTEMPERATURE PROTECTION
s
LOW STAND-BY CURRENT
s
ADJUSTABLE CURRENT LIMITATION
BLOCK DIAGRAM
PENTAWATT HV
Power SO-10
DESCRIPTION
VIPer20B鈩?combines on the same silicon chip a
state-of-the-art PWM circuit together with an
optimized high voltage avalanche rugged Vertical
Power MOSFET (400V 1.3A).
Typical applications cover off line power supplies
with a secondary max power capability of 30W. It
is compatible from both primary or secondary
regulation loop despite using around 50% less
components when compared with a discrete
solution. Burst mode operation is an additional
feature of this device, offering the possibility to
operate in stand-by mode without extra
components.
OSC
DRAIN
ON/OFF
OSCILLATOR
SECURITY
LATCH
VDD
UVLO
LOGIC
R/S
FF
S
Q
PWM
LATCH
R1
S
FF
R2 R3
Q
OVERTEMP.
DETECTOR
0.5 V
+
_
2
碌s
delay
300 ns
Blanking
+
_
+
0.5V
_
6 V/A
_
13 V
+
ERROR
AMPLIFIER
CURRENT
AMPLIFIER
4.5 V
COMP
SOURCE
FC00490
September 1999
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