TOP242-249 POWERINT [Power Integrations, Inc.], TOP242-249 Datasheet - Page 27

• Manufacturer Part Number: TOP242-249
• Description: Family Extended Power, Design Flexible,Integrated Off-line Switcher
• Manufacturer: POWERINT [Power Integrations, Inc.]

TOPSwitch-II vs. TOPSwitch-GX
Table 4 compares the features and performance differences
between TOPSwitch-GX and TOPSwitch-II. Many of the new
features eliminate the need for additional discrete components.
Table 4. Comparison Between TOPSwitch-II and TOPSwitch-GX. (continued on next page) *Not available
Key Application Considerations
Function
Soft-Start
External Current Limit
DC
Line Feed Forward with N/A*
DC
Line OV Shutdown
Line UV Detection
Switching Frequency
Switching Frequency
Option (Y and R
Packages)
Frequency Jitter
Frequency Reduction
MAX
MAX
Reduction
TOPSwitch-II
N/A*
N/A*
67%
N/A*
N/A*
100 kHz ±10%
N/A*
N/A*
N/A*
TOPSwitch-GX
10 ms
Programmable
100% to 30% of
default current
limit
78%
78% to 38%
Single resistor
programmable
Single resistor
programmable
132 kHz ±6%
66 kHz ±7%
±4 kHz@132 kHz 9,46
±2 kHz@66 kHz
At a Duty Cycle
below 10%
Other features increase the robustness of design allowing cost
savings in the transformer and other power components.
11,20,21, • Smaller transformer
24,25,27, • Higher efficiency
28,34,35, • Allows power limiting (constant over-
26,27,28,
38,39
7
7,11,17,
31,40
11,17,19, • Increases voltage withstand cap-
26,27,28,
31,33,40
11,17,18, • Prevents auto-restart glitches
26,27,28,
31,32,40
13,15
14,15
7
Figures TOPSwitch-GX Advantages
• Limits peak current and voltage
• Eliminates external components
• Reduces or eliminates output
• Allows use of larger device for lower
• Smaller input cap (wider dynamic
• Higher power capability (when used
• Allows use of Schottky secondary
• Rejects line ripple
• Smaller transformer
• Below start of conducted EMI limits
• Lower losses when using RC and
• Allows for higher efficiency in
• Lower EMI (second harmonic below
• Reduces conducted EMI
• Zero load regulation without dummy
• Low power consumption at no load
component stresses during start-up
used for soft-start in most
applications
overshoot
load power independent of line
voltage
losses, higher efficiency and smaller
heatsink
range)
with RCD clamp for large V
rectifier diode for up to 15 V output
for high efficiency
ability against line surge
during power down
RCD snubber for noise reduction in
video applications
standby mode
150 kHz)
load
August 8, 2000
TOP242-249
OR
7/01
)
E
27