ADDC02808PB(Rev0) View Datasheet(PDF) - Analog Devices
Part Name
Description
Manufacturer
ADDC02808PB Datasheet PDF : 20 Pages
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ADDC02808PB
In almost all systems the output ground of the converter is
CS114: This test measures the ability of the converter to
ultimately connected to the input ground of the system. The
operate correctly during and after being subjected to currents
parasitic capacitances and inductances in this connection will
injected into bulk cables in the 10 kHz to 400 MHz range. Its
affect the common-mode voltage and the CE102
purpose is to simulate currents that would be developed in these
measurement. In addition, the inductive impedance of this
cables due to electromagnetic fields generated by antenna
ground connection can cause resonances, thereby affecting the
transmissions. The converter is designed to meet the
performance of the common-mode filter in the power supply.
requirements of this test when the current is injected on the
In response to these ambiguities, the Analog Devices’
input power leads cable. Consult factory for more information.
converter has been tested for CE102 under a constant load
CS115: This test measures the ability of the converter to
and with the output ground floating. While these
operate correctly during and after being subjected to 30 ns long
measurements are a good indication of how the converter will
pulses of current injected into bulk cables. Its purpose is to
operate in the final system configuration, the user should
simulate transients caused by lightning or electromagnetic
confirm CE102 testing in the final system configuration.
pulses. The converter is designed to meet this requirement
OBSOLETE CE101: This test measures emissions on the input leads in the
frequency range between 30 Hz and 10 kHz. The intent of
this requirement is to ensure that the dc/dc converter does not
corrupt the power quality (allowable voltage distortion) on the
power busses present on the platform. There are several
CE101 limit curves in MIL-STD-461D. The most stringent
one app-licable for the converter is the one for submarine
applications. Figure 11 shows that the converter easily meets
this requirement (the return line measurement is similar). The
components at 60 Hz and its harmonics are a result of ripple in
the output of the power source used to supply the converter.
CE102: This test measures emissions in the frequency range
between 10 kHz and 10 MHz. The measurements are made
on both of the input leads of the converter which are
connected to the power source through LISNs. The intent of
this requirement in the lower frequency portion of the
requirement is to ensure that the dc/dc converter does not
when applied to its input power leads cable. Consult factory for
more information.
CS116: This test measures the ability of the converter to
operate correctly during and after being subjected to damped
sinusoid transients in the 10 kHz to 100 MHz range. Its
purpose is to simulate current and voltage waveforms that would
occur when natural resonances in the system are excited. The
converter is designed to meet this requirement when applied to
its input power leads cable. Consult factory for more information.
RE101: This requirement limits the strength of the magnetic
field created by the converter in order to avoid interference with
sensitive equipment located nearby. The measurement is made
from 30 Hz to 100 kHz. The most stringent requirement is for
the Navy. Figure 13 shows the test results when the pickup coil
is held 7 cm above the converter. As can be seen, the converter
easily meets this requirement.
RE102: This requirements limits the strength of the electric
corrupt the power quality (allowable voltage distortion) on the
field emissions from the power converter to protect sensitive
power busses present on the platform. At higher frequencies,
receivers from interference. The measurement is made from
the intent is to serve as a separate control from RE102 on
10 kHz to 18 GHz with the antenna oriented in the vertical
potential radiation from power leads which may couple into
plane. For the 30 MHz and above range the standard calls for
sensitive electronic equipment.
the measurement to be made with the antenna oriented in the
Figure 12 shows the CE102 limit and the measurement taken
horizontal plane, as well.
from the +VIN line. While the measurement taken from the
input return line is slightly different, both comfortably meet
the MIL-STD-461D, CE102 limit.
In a typical power converter system setup, the radiated emis-
sions can come from two sources: 1) the input power leads as
they extend over the two meter distance between the LISNs and
CS101: This test measures the ability of the converter to
the converter, as required for this test, and 2) the converter
reject low frequency differential signals, 30 Hz to 50 kHz,
output leads and load. The latter is likely to create significant
injected on the dc inputs. The measurement is taken on the
emissions if left uncovered since minimal EMI filtering is
output power leads. The intent is to ensure that equipment
provided at the converter’s output. It is typical, however,
performance is not degraded from ripple voltages associated
that the power supply and its load would be contained in a
with allowable distortion of power source voltage waveforms.
conductive enclosure in applications where this test is applicable.
Figure 7 shows a typical audio susceptibility graph. Note that
A metal screen enclosure was therefore used to cover the
according to the MIL-STD-461D test requirements, the
converter and its load for this test.
injected signal between 30 Hz and 5 kHz has an amplitude of
2 V rms and from 5 kHz to 50 kHz the amplitude decreases
inversely with frequency to 0.2 V rms. The curve of the
injected signal should be multiplied by the audio susceptibility
curve to determine the output ripple at any frequency. When
this is done, the worst case output ripple at the frequency of
the input ripple occurs at 5 kHz, at which point there is
typically a 25 mV peak-to-peak output ripple.
Figure 14 shows test results for the vertical measurement and
compares them against the most stringent RE102 requirement;
the horizontal measurement (30 MHz and above) was similar.
As can be seen, the emissions just meet the standard in the
18 MHz–28 MHz range. This component of the emissions is
due to common-mode currents flowing through the input power
leads. As mentioned in the section on CE102 above, the level
of common-mode current that flows is dependent on how the
It should be noted that MIL-STD-704 has a more relaxed
load is connected. This measurement is therefore a good
requirement for rejection of low frequency differential signals
indication of how well the converter will perform in the final
injected on the dc inputs than MIL-STD-461D. MIL-STD-
configuration, but the user should confirm RE102 testing in the
704 calls for a lower amplitude ripple to be injected on the
final system.
input in a narrower frequency band, 10 Hz to 20 kHz.
–16–
REV. 0
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