Test configurations, Design considerations, Input filtering – GE Industrial Solutions Naos Raptor 60A User Manual

Page 11: Output filtering, Lineage power 11, Figure 38. output ripple and noise test setup

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Data Sheet
December 6, 2010

Naos Raptor 60A: Non Isolated Power Modules

5 – 13.8Vdc input; 0.6Vdc to 5.0Vdc Output; 60A output current


LINEAGE

POWER

11

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 37. 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 38. 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 39. 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 60A 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 40 shows the input ripple
voltage for various output voltages at 60A of load
current with 2x22 µF or 4x22 µF ceramic capacitors
and an input of 12V.

Input

Ri

ppl

e

Vo

ltage (m

Vp-

p

)

0

50

100

150

200

250

0

1

2

3

4

5

2x22uF

4x22uF

Output

Voltage

(Vdc)

Figure 40. Input ripple voltage for various output
voltages with 2x22 µF or 4x22 µF ceramic
capacitors at the input (60A load). Input voltage is
12V.

Output Filtering

The Naos Raptor 60A 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
performance of the module can be achieved by using

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