LYT1402-1604
ꢐꢃꢑꢒꢌ ꢓꢈꢈꢉ ꢔꢊeꢁ ꢕꢈꢊꢄeꢆ ꢖꢗ ꢣꢎꢉꢠꢌ
ꢇꢁꢉꢁꢡꢃꢌꢈꢊ ꢜꢇꢤꢝꢞ ꢕꢊeeꢘꢙꢒeeꢚꢃꢎꢑ ꢛꢃꢈꢆe ꢜꢛ1ꢝꢞ
ꢀꢟꢍꢕꢥꢐ ꢜꢦ1ꢝꢞ ꢍeꢎꢧe Reꢧꢃꢧꢌꢈꢊ ꢜR6ꢝ
ꢐꢃꢑꢒꢌ ꢓꢈꢈꢉ ꢔꢊeꢁ ꢕꢈꢊꢄeꢆ ꢖꢗ ꢌꢒe
ꢕꢊeeꢘꢙꢒeeꢚꢃꢎꢑ ꢛꢃꢈꢆe ꢜꢛ1ꢝꢞ ꢟꢠꢌꢉꢠꢌ
ꢇꢁꢉꢁꢡꢃꢌꢈꢊ ꢜꢇꢢꢝꢞ ꢣꢎꢆꢠꢡꢌꢈꢊ ꢜꢓꢤꢝ
ꢀꢁꢂꢃT
ꢄꢃTꢂꢃT
ꢀꢁꢂꢃꢄꢃꢅeꢆ ꢇꢈꢉꢉeꢊ
ꢋeꢁꢌ ꢍꢃꢎꢏ
ꢀꢦꢓꢐꢣꢕꢦꢨꢇꢐꢣꢟꢨ ꢩꢃꢎ
ꢇꢁꢉꢁꢡꢃꢌꢈꢊ ꢜꢇꢪꢝꢞ ꢛꢃvꢃꢆeꢊ
Reꢧꢃꢧꢌꢈꢊꢧ Rꢤ ꢫ Rꢬ
Bꢭꢩꢔꢍꢍ ꢩꢃꢎ
ꢇꢁꢉꢁꢡꢃꢌꢈꢊ ꢇꢬ
ꢓꢭꢐꢍꢮꢃꢌꢡꢒꢘ1
ꢜꢦ1ꢝ
ꢩꢣꢘ7ꢯꢰꢯꢘ061016
Figure 8. Design Example DER-548 PCB Layout Showing the Critical Components and Loop Areas with LYTSwitch-1 in Low-Side Buck Configuration.
Since the switch MOSFET is referenced to ground, the low-side buck
configuration would also give an advantage of using a low-cost
Quick Design Checklist
Maximum Drain Voltage
off-the-shelf dog bone type inductor as demonstrated in the design
Verify that the peak Drain voltage stress (VDS) does not exceed
example DER-548. The addition of a small capacitor C4 (Figure 7) is
725 V under all operating conditions, including start-up and fault
needed to couple the high-voltage referenced signal of the output
conditions.
voltage into the MULTIFUNCTION pin of the IC through the resistor
divider network R2, R3 and R5. Based on the simulation and bench
Maximum Drain Current
results capacitance of 100 pF is a good compromise between AC line
Measure the peak Drain current under all operation conditions
rejection and flatness of the output voltage during the off-time of the
(including start-up and fault conditions). Look for transformer
switch. Based on capacitance tolerance, 68 pF to 150 pF range can
saturation (usually occurs at highest operating ambient temperatures).
be used.
Verify that the peak current is less than the stated Absolute Maximum
Rating in the data sheet.
Design Tools
Thermal Check
Up-to-date information on design tools can be found at the Power
At maximum output power, for both minimum and maximum line
Integrations web site: www.power.com
voltage and maximum ambient temperature verify that component’s
LYTSwitch-1 PIXls spreadsheet is located at PI Expert online:
https://piexpertonline.power.com/site/login
temperature specifications are not exceeded for the LYTSwitch-1,
transformer, output diodes and output and input capacitors.
6
Rev. B 07/16
www.power.com
POWERINT [ Power Integrations ]
