ACT30
Active- Semi
Rev 5, 05-Jun-09
Application Example
The application circuit in Figure 5 provides a
5V/0.75A constant voltage/constant current output.
The performance of this circuit is summarized in
Table 2.
Table 2:
System Performance of Circuit in Figure 5
110VAC
0.09W
0.75A
65%
220VAC
0.15W
0.75A
67%
Standby Power
Current Limit
Full Load Efficiency
Layout Considerations
The following should be observed when doing
layout for the ACT30:
1) Use a "star point" connection at the GND pin of
ACT30 for the VDD bypass components (C5 and
C6 in Figure 5), the input filter capacitor (C2 in
Figure 5) and other ground connections on the
primary side.
2) Keep the loop across the input filter capacitor,
the transformer primary windings, and the high
voltage transistor, and the ACT30 as small as
possible.
3) Keep ACT30 pins and the high voltage transistor
pins as short as possible.
4) Keep the loop across the secondary windings,
the output diode, and the output capacitors as
small as possible.
5) Allow enough copper area under the high voltage
transistor, output diode, and current shunt
resistor for heat sink.
Innovative PowerTM
ActiveSwitcherTM is a trademark of Active-Semi.
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Copyright © 2009 Active-Semi, Inc.
ACTIVE-SEMI [ ACTIVE-SEMI, INC ]
