Datasheet
TOP242-250
16
I
4/03
General Information & Table of Contents
Product Selector Guide 1
Data Sheets 2
Application Notes 3
Design Ideas 4
Design Tools 5
Quality and Reliability 6
Package Information 7
DPA-Switch
 DC-DC Seminar 8
LinkSwitch 
&
 TinySwitch-II
 AC-DC Seminar 9
TOPSwitch-GX
 AC-DC Seminar 10
Sales Representatives and Distributors 11
Typical Uses of LINE-SENSE (L) and EXTERNAL CURRENT LIMIT (X) Pins
XF
PI-2617-050100
DC
Input
Voltage
+
-
D
CS D
S
C
CONTROL
L
CLXS F D
PI-2618-040501
DC
Input
Voltage
+
-
D
S
C
CONTROL
L
2MΩR
LS
 V
UV
 = I
UV
 x R
LS
 V
OV 
=
I
OV 
x
R
LS
For R
LS
 = 2 MΩ
 V
UV
 = 100 VDC
 V
OV 
=
450 VDC
DC
MAX
@100 VDC = 78%
DC
MAX
@375 VDC = 38%
PI-2510-040501
DC
Input
Voltage
+
-
DM
S
C
 V
UV
 = R
LS
 x I
UV
For Value Shown
 V
UV
 = 100 VDC
R
LS
6.2 V
2 MΩ
22 kΩ
CONTROL
PI-2620-040501
DC
Input
Voltage
+
-
D
S
C
CONTROL
L
2 MΩ
30 kΩ
R
LS
1N4148
 V
OV 
 = I
OV 
x
R
LS
For Values Shown
 V
OV
 = 450 VDC
X
PI-2623-040501
DC
Input
Voltage
+
-
D
S
C
R
IL
For R
IL 
= 12 kΩ 
 I
LIMIT 
 = 69% 
See fig. 55 for other 
resistor values (R
IL
)
For R
IL 
= 25 kΩ 
 I
LIMIT 
 = 43% 
CONTROL
X
PI-2624-040501
DC
Input
Voltage
+
-
D
S
C
2.5 MΩR
LS
6 kΩ
R
IL
100% @ 100 VDC
63% @ 300 VDC
I
LIMIT 
=
I
LIMIT 
= 
CONTROL
Figure 16. Three Terminal Operation (LINE-SENSE and
EXTERNAL CURRENT LIMIT Features Disabled.
FREQUENCY Pin can be tied to SOURCE or
CONTROL Pin).
Figure 17. Line-Sensing for Under-Voltage, Overvoltage and
Line Feed Forward.
Figure 18. Line-Sensing for Under-Voltage Only (Overvoltage
Disabled).
Figure 19. Line-Sensing for Overvoltage Only (Under-Voltage
Disabled). Maximum Duty Cycle will be reduced at
Low Line.
Figure 20. Externally Set Current Limit.
Figure 21. Current Limit Reduction with Line Voltage.










