Power integrations InnoSwitch3 User Manual

Rev. A 10/18
29
Application NoteAN-72
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Quick Design Checklist
As with any power supply, the operation of all InnoSwitch3 designs
should be veried on-the-bench to make sure that component limits
are not exceeded under worst-case conditions. As a minimum, the
following tests are strongly recommended:
Maximum Drain Voltage
Verify that V
DS
of InnoSwitch3 and SR FET do not exceed 90% of
breakdown voltages at the highest input voltage and peak (overload)
output power in normal operation and during start-up.
Maximum Drain Current
At maximum ambient temperature, maximum input voltage and peak
output (overload) power. Review Drain current waveforms for any
signs of transformer saturation or excessive leading-edge current
PI-8377-020918
Secondary
Control
Primary
Control
Power
FET
Mylar 0.4 mm
Heat Sink
0.5 mm
Thermal Pad
0.4 mm
6.6 mm
4.2 mmInnoSwitch3
InSOP-24D
InSOP-24D
d ~ 4.2 mm
Heat Sink
d > 6.6 mm
d > 6.6 mm
d > 6.6 mm
Mylar 0.4 mm
Thermal Pad
InSOP-24D
Figure 24. Simplied Diagram of Heat Spreader Attachment to an InSOP-24D Package.
spikes at start-up. Repeat tests under steady-state conditions and
verify that the leading edge current spike is below I
LIMIT(MIN)
at the end
of t
LEB(MIN)
. Under all conditions, the maximum Drain current for the
primary MOSFET should be below the specied absolute maximum
ratings.
Thermal Check
At specied maximum output power, minimum input voltage and
maximum ambient temperature. Verify that temperature specication
limits for InnoSwitch3 IC, transformer, output SR FET, and output
capacitors are not exceeded. Enough thermal margin should be
allowed for part-to-part variation of MOSFET R
DS(ON)
. At low-line,
maximum power, a maximum InnoSwitch3 SOURCE pin temperature
of 110 °C is recommended to allow for R
DS(ON)
variation.

Power integrations InnoSwitch3 Specifications

General

Brand	Power integrations
Model	InnoSwitch3
Category	Switch
Language	English