TOP242-250
V
C
0
1
DRAIN (D)
CONTROL (C)
Z
C
INTERNAL
SUPPLY
SHUNT REGULATOR/
ERROR AMPLIFIER
+
-
SOFT START
5.8 V
4.8 V
-
5.8 V
+
INTERNAL UV
COMPARATOR
I
FB
V
I (LIMIT)
CURRENT
LIMIT
ADJUST
SOFT
START
-
÷ 8
ON/OFF
+
V
+ V
T
BG
SHUTDOWN/
AUTO-RESTART
CURRENT LIMIT
COMPARATOR
EXTERNAL
CURRENT LIMIT (X)
HYSTERETIC
THERMAL
STOP LOGIC
SHUTDOWN
1 V
LINE-SENSE (L)
CONTROLLED
TURN-ON
V
BG
GATE DRIVER
STOP SOFT-
OV/UV
START
D
LINE
SENSE
MAX
DC
DC
MAX
MAX
CLOCK
SAW
S
R
Q
HALF
FREQ.
-
LEADING
EDGE
BLANKING
FREQUENCY (F)
+
OSCILLATOR WITH JITTER
PWM
COMPARATOR
LIGHT LOAD
FREQUENCY
REDUCTION
R
E
SOURCE (S)
PI-2639-060600
Figure 2a. Functional Block Diagram (Y, R or F Package).
V
C
0
CONTROL (C)
DRAIN (D)
Z
C
INTERNAL
SUPPLY
1
SHUNT REGULATOR/
ERROR AMPLIFIER
+
SOFT START
5.8 V
4.8 V
-
-
5.8 V
+
INTERNAL UV
COMPARATOR
I
FB
V
I (LIMIT)
CURRENT
LIMIT
ADJUST
SOFT
START
-
÷ 8
ON/OFF
+
SHUTDOWN/
AUTO-RESTART
CURRENT LIMIT
COMPARATOR
V
+ V
T
BG
V
STOP LOGIC
HYSTERETIC
THERMAL
SHUTDOWN
MULTI-
FUNCTION (M)
CONTROLLED
TURN-ON
BG
GATE DRIVER
STOP SOFT-
OV/UV
DC
START
D
LINE
SENSE
MAX
DC
MAX
MAX
CLOCK
SAW
S
R
Q
-
LEADING
EDGE
BLANKING
+
OSCILLATOR WITH JITTER
PWM
COMPARATOR
LIGHT LOAD
FREQUENCY
REDUCTION
R
E
SOURCE (S)
PI-2641-061200
Figure 2b. Functional Block Diagram (P or G Package).
M
12/04
3
POWERINT [ Power Integrations ]
