TOP412/414
V
C
0
1
CONTROL
DRAIN
INTERNAL
SUPPLY
Z
C
SHUTDOWN/
AUTO-RESTART
SHUNT REGULATOR/
ERROR AMPLIFIER
+
-
÷ 8
-
5.7 V
4.7 V
5.7 V
+
POWER-UP
RESET
EXTERNALLY
TRIGGERED
SHUTDOWN
+
R
S
Q
-
V
I
LIMIT
Q
I
THERMAL
SHUTDOWN
FB
CONTROLLED
TURN-ON
GATE
DRIVER
OSCILLATOR
D
MAX
CLOCK
SAW
S
Q
Q
-
LEADING
EDGE
+
R
BLANKING
PWM
COMPARATOR
MINIMUM
ON-TIME
DELAY
R
E
SOURCE
PI-1746-011796
Figure 2. Functional Block Diagram.
Pin Functional Description
DRAIN Pin:
Output MOSFET drain connection. Provides internal bias
current during start-up operation via an internal switched high-
voltage current source. Internal current sense point.
1
2
3
4
8
7
6
5
SOURCE
SOURCE (HV RTN)
SOURCE (HV RTN)
SOURCE (HV RTN)
DRAIN
SOURCE
SOURCE
CONTROL Pin:
Error amplifier and feedback current input pin for duty cycle
control. Internal shunt regulator connection to provide internal
biascurrentduringnormaloperation. Triggerinputforlatching
shutdown. It is also used as the supply bypass and auto-restart/
compensation capacitor connection point.
CONTROL
G Package (SMD-8)
SOURCE Pin:
Output MOSFET source connection. Primary-side circuit
common, power return, and reference point.
PI-2208-120798
Figure 3. Pin Configuration.
A
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2
POWERINT [ Power Integrations ]
