SLIN-20F1A0 BEL [Bel Fuse Inc.], SLIN-20F1A0 Datasheet - Page 12

• Manufacturer Part Number: SLIN-20F1A0
• Description: 2.4 Vdc - 5.5 Vdc Input, 0.6 Vdc - 3.63 Vdc /20 A Output
• Manufacturer: BEL [Bel Fuse Inc.]

Input Filtering
The SLIN-20F1Ax module should be connected to a low ac-impedance source. A highly inductive source can
affect the stability of the module. An input capacitor must be placed directly adjacent to the input pin of the
module, to minimize input ripple voltage and ensure module stability.
To minimize input voltage ripple, low-ESR ceramic capacitors are recommended at the input of the module.
Figure A below shows the input ripple voltage for various output voltages at 20A of load current with 2x47 µF or
4x47 µF ceramic capacitors and an input of 5V. Figure B below shows data for the 3.3Vin case, with 2x47µF or
4x47µF of ceramic capacitors at the input.
Figure A
Output Filtering
The SLIN-20F1Ax modules are designed for low output ripple voltage and will meet the maximum output ripple
specification with 0.1 µF ceramic and 10 µF ceramic capacitors at the output of the module. However, additional
output filtering may be required by the system designer for a number of reasons. First, there may be a need to
further reduce the output ripple and noise of the module. Second, the dynamic response characteristics may
need to be customized to a particular load step change.
To reduce the output ripple and improve the dynamic response to a step load change, additional capacitance at
the output can be used. Low ESR ceramic and polymer capacitors are recommended to improve the dynamic
response of the module. Figure A on the next page provides output ripple information for different external
capacitance values at various Vo and for load currents of 20A while maintaining an input voltage of 5V. Figure B
on the next page shows the performance with a 3.3V input. For stable operation of the module, limit the
capacitance to less than the maximum output capacitance as specified in the electrical specification table.
Optimal performance of the module can be achieved by using the Tunable Loop
data sheet.
December 2, 2010
NON-ISOLATED DC/DC CONVERTERS
2.4 Vdc - 5.5 Vdc Input, 0.6 Vdc - 3.63 Vdc /20 A Output
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Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 • Tel [phone] • Fax [phone] •
Output Voltage (Vdc)
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2x47uF
4x47uf
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Figure B
Bel Power Inc., a subsidiary of Bel Fuse Inc.
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Output Voltage (Vdc)
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feature described later in this
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www.belfuse.com
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