Lineage Power

9

Data Sheet

April 2008

dc-dc Converters; 36 to 75 Vdc Input, 5 Vdc Output; 250 W to 300 W

FW250A1 and FW300A1 Power Modules:

8-1757 (C)

Note: Tested with a 10 µF aluminum and a 1.0 µF ceramic capacitor

across the load.

Figure 13. Typical FW300A1 Start-Up Transient at

Room Temperature, 48 V Input

Test Configurations

8-203 (C).o

Note: Measure input reflected-ripple current with a simulated source

tery impedance. Measure current as shown above.

Figure 14. Input Reflected-Ripple Test Setup

8-513 (C).m

Note: Use a 0.1 µF ceramic capacitor and a 10 µF aluminum or

tantalum capacitor. Scope measurement should be made

using a BNC socket. Position the load between 50 mm and

76 mm (2 in. and 3 in.) from the module.

Figure 15. Peak-to-Peak Output Noise

Measurement Test Setup

8-683 (C).f

Note: All measurements are taken at the module terminals. When

socketing, place Kelvin connections at module terminals to

avoid measurement errors due to socket contact resistance.

Figure 16. Output Voltage and Efficiency

Measurement Test Setup

Design Considerations

Input Source Impedance

The power module should be connected to a low

ac-impedance input source. Highly inductive source

impedances can affect the stability of the power mod-

ule. For the test configuration in Figure 14, a 100 µF

electrolytic capacitor (ESR < 0.3

Ω at 100 kHz)

mounted close to the power module helps ensure sta-

bility of the unit. For other highly inductive source

impedances, consult the factory for further application

guidelines.

TIME, t (5 ms/div)

TO OSCILLOSCOPE

12 µH

BATTERY

Cs 220 µF

ESR < 0.1

Ω

@ 20

°C, 100 kHz

100 µF

ESR < 0.3

Ω

@ 100 kHz

1.0 µF

RESISTIVE

LOAD

SCOPE

COPPER STRIP

10.0 µF

SENSE(+)

SENSE(–)

LOAD

CONTACT AND

DISTRIBUTION LOSSES

SUPPLY

CONTACT

RESISTANCE

η

()

()

--------------------------------------------------



 x 100

%

=