Test configurations, Design considerations, Input filtering – GE Industrial Solutions Naos Raptor 50A User Manual
Page 8: Output filtering, Lineage power 8, Figure 20. output ripple and noise test setup
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Data Sheet
October 31, 2011
Naos Raptor 50A: Non Isolated Power Module:
5 – 14Vdc input; 0.6Vdc to 2.0Vdc Output; 50A output current
LINEAGE
POWER
8
Test Configurations
TO OSCILLOSCOPE
CURRENT PROBE
L
TEST
1μH
B
A
TTE
R
Y
C
S
1000μF
Electrolytic
E.S.R.<0.1
Ω
@ 20°C 100kHz
2x100μF
Tantalum
V
IN
(+)
COM
NOTE: Measure input reflected ripple current with a simulated
source inductance (L
TEST
) of 1μH. Capacitor C
S
offsets
possible battery impedance. Measure current as shown
above.
C
IN
Figure 19. Input Reflected Ripple Current Test
Setup.
NOTE: All voltage measurements to be taken at the module
terminals, as shown above. If sockets are used then
Kelvin connections are required at the module terminals
to avoid measurement errors due to socket contact
resistance.
V
O
(+)
COM
1uF
.
RESISTIVE
LOAD
SCOPE
COPPER STRIP
GROUND PLANE
10uF
Figure 20. Output Ripple and Noise Test Setup.
V
O
COM
V
IN
(+)
COM
R
LOAD
R
contact
R
distribution
R
contact
R
distribution
R
contact
R
contact
R
distribution
R
distribution
V
IN
V
O
NOTE: All voltage measurements to be taken at the module
terminals, as shown above. If sockets are used then
Kelvin connections are required at the module terminals
to avoid measurement errors due to socket contact
resistance.
Figure 21. Output Voltage and Efficiency Test
Setup.
η =
V
O
. I
O
V
IN
. I
IN
x
100
%
Efficiency
Design Considerations
Input Filtering
The Naos Raptor 50A module should be connected
to a low-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, low-ESR polymer
and ceramic capacitors are recommended at the input
of the module. Figure 22 shows the input ripple
voltage for various output voltages at 50A of load
current with 2x22 µF or 4x22 µF ceramic capacitors
and an input of 12V. A minimum input capacitance of
3x22 µF ceramic capacitors in order to handle worst-
case conditions over the entire input voltage, output
voltage and load range. For more specific conditions,
please consult your Lineage Power technical
representative.
0
10
20
30
40
50
60
70
80
90
100
0.5
1
1.5
2
2x22uF
4x22uF
Figure 22. Input ripple voltage for various output
voltages with 2x22 µF or 4x22 µF ceramic
capacitors at the input (50A load). Input voltage is
12V.
Output Filtering
The Naos Raptor 50A modules are designed for low
output ripple voltage and will meet the maximum
output ripple specification with no external capacitors.
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 are recommended to improve
the dynamic response of the module. For stable
operation of the module, limit the capacitance to less
than the maximum output capacitance as specified in
the electrical specification table. Optimal