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VAT2-S5-D5-SMT_08 Datasheet, PDF (3/3 Pages) CUI INC – dc-dc converter
PART NUMBER: VAT2-SMT series
DESCRIPTION: dc-dc converter
rev.
page 3 of 3
date 02/2008
APPLICATION NOTES:
- Input filtering
To reduce the reflected ripple current and minimize EMI,
especially when the converter input is more than 2” away from
the DC source, it is recommended to connect a low ESR
electrolytic capacitor between Vin and Gnd. The values
suggested are as shown in Table 1. If additional filtering is
required, the capacitance may be increased, or expanded to
an LC network as shown in Figure 1.
TABLE 1
- Output filtering
Output capacitance may be increased for additional filtering,
but should not exeed 10μF or expanded to an LC network as
in Figure 1.
FIGURE 1
- Minimum loading
The converter needs a minimum of 10% loading to maintain
output regulation. Operation under no-load conditions will not
cause immediate damages but may reduce reliability, and
cause performance not to meet specifications.
- Regulation
With a semi-regulated design, the converter’s output voltage
varies with load current and will change proportionally to the
input voltage. If regulated output is needed, an external
regulator can be used as shown in Figure 2.
- Protection
The converter has minimal protection against input over-
voltage or output over-load, and may be permanently damaged
if exposed to these conditions. An input clamping device can
be used for input voltage limiting. An input fuse or an output
fuse also be used to protect against over-loading.
- Dual outputs used as a single output
The +Vout and -Vout can be used to obtain a single output
that is the sum of the two outputs. In this case, the COM pin
shouldn’t be used.
- External Regulator
An external 3-terminal regulator can be connected to the
output of the converter to achieve full regulation. Make sure
the converter’s output voltage provides sufficient head room
for the regulator. An additional benefit is that the built-in
protection features in the regulator, such as OCP, OTP, etc,
will protect the converter also. In a complimentory supply, a
negative output regulator must be used to achieve the
negative regulated output.
RECOMMENDED REFLOW SOLDERING PROFILE
FIGURE 2
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2382