SLAN-03D2A0 Datasheet, PDF (11/25 Pages) Bel Fuse Inc. – NON-ISOLATED DC/DC CONVERTERS

NON-ISOLATED DC/DC CONVERTERS
3 Vdc – 14.4 Vdc Input, 0.6 Vdc - 5.5 Vdc /3 A Outputs
Mar. 16, 2012
Design Considerations
Bel Power Inc., a subsidiary of Bel Fuse Inc.
Input Filtering
The SLAN-03D2Ax module should be connected to a low ac-impedance source. A highly inductive source can
affect the stability of the module. An input capacitance 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, ceramic capacitors are recommended at the input of the module. Figure 37
shows the input ripple voltage for various output voltages at 3A of load current with 1x22µF or 2x22µF ceramic
capacitors and an input of 12V.
Figure 37
Note: Input ripple voltage for various output voltages with 1x22 µF or 2x22 µF ceramic capacitors at the input
(3A load). Input voltage is 12V.
Output Filtering
These 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 polymer and ceramic capacitors are recommended to improve the dynamic
response of the module. Figure 38 provides output ripple information for different external capacitance values at
various Vo and a full load current of 3A. 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^TM feature described later in this data sheet.
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302  Tel [phone]  Fax [phone]  www.belfuse.com
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