LNK363G POWERINT [Power Integrations, Inc.], LNK363G Datasheet - Page 7

• Manufacturer Part Number: LNK363G
• Description: Energy Effi cient, Low Power Off-Line Switcher IC
• Manufacturer: POWERINT [Power Integrations, Inc.]

Optocoupler
Place the optocoupler physically close to the LinkSwitch-XT to
minimize the primary-side trace lengths. Keep the high current,
high voltage drain and clamp traces away from the optocoupler
to prevent noise pick up.
Output Diode
For best performance, the area of the loop connecting the
secondary winding, the output diode and the output fi lter
capacitor should be minimized. In addition, suffi cient copper
area should be provided at the anode and cathode terminals
of the diode for heat sinking. A larger area is preferred at the
quiet cathode terminal. A large anode area can increase high
frequency radiated EMI.
Quick Design Checklist
As with any power supply design, all LinkSwitch-XT designs
should be verifi ed on the bench to make sure that component
specifi cations are not exceeded under worst-case conditions. The
following minimum set of tests is strongly recommended:
1. Maximum drain voltage – Verify that V
650 V at the highest input voltage and peak (overload) output
power. The 50 V margin to the 700 V BV
gives margin for design variation, especially in Clampless
designs.
DS
DSS
does not exceed
specifi cation
2. Maximum drain current – At maximum ambient temperature,
3. Thermal Check – At specifi ed maximum output power,
Design Tools
Up-to-date information on design tools can be found at the
Power Integrations web site: www.powerint.com.
maximum input voltage and peak output (overload) power,
verify drain current waveforms for any signs of transformer
saturation and excessive leading-edge current spikes at
startup. Repeat under steady state conditions and verify that
the leading-edge current spike event is below I
end of the t
current should be below the specifi ed absolute maximum
ratings.
minimum input voltage and maximum ambient temperature,
verify that the temperature specifi cations are not exceeded
for LinkSwitch-XT, transformer, output diode and output
capacitors. Enough thermal margin should be allowed for
part-to-part variation of the R
specifi ed in the data sheet. Under low line, maximum power,
a maximum LinkSwitch-XT SOURCE pin temperature of
105 °C is recommended to allow for these variations.
LEB(MIN)
. Under all conditions, the maximum drain
DS(ON)
LNK362-364
of LinkSwitch-XT as
LIMIT(MIN)
12/05
C
at the
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