Data Sheet
ESTW025A0F Series Eighth-Brick Power Modules
36–75Vdc Input; 3.3Vdc Output; 25A Output
October 11, 2011
Test Configurations
Design Considerations
Input Filtering
CURRENT PROBE
Vin+
TO OSCILLOSCOPE
The power module should be connected to a low
ac-impedance source. Highly inductive source
impedance can affect the stability of the power
module. For the test configuration in Figure 7 a 100μF
electrolytic capacitor (ESR<0.7 at 100kHz), mounted
close to the power module helps ensure the stability of
the unit. Consult the factory for further application
guidelines.
LTEST
12μH
CS 220μF
100μF
E.S.R.<0.1
@ 20°C 100kHz
Vin-
Safety Considerations
For safety-agency approval of the system in which the
power module is used, the power module must be
installed in compliance with the spacing and
separation requirements of the end-use safety agency
standard, i.e. UL60950-1, CSA C22.2 No.60950-1,
and VDE0805-1(IEC60950-1).
NOTE: Measure input reflected ripple current with a simulated
source inductance (LTEST) of 12μH. Capacitor CS offsets
possible battery impedance. Measure current as shown
above.
Figure 7. Input Reflected Ripple Current Test
Setup.
COPPER STRIP
If the input source is non-SELV (ELV or a hazardous
voltage greater than 60 Vdc and less than or equal to
75Vdc), for the module’s output to be considered as
meeting the requirements for safety extra-low voltage
(SELV), all of the following must be true:
VO(+)
VO(–)
RESISTIVE
LOAD
SCOPE
.
The input source is to be provided with reinforced
insulation from any other hazardous voltages,
including the ac mains.
0.01uF
10uF
0.1uF
GROUND PLANE
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.
.
One VIN pin and one VOUT pin are to be grounded,
or both the input and output pins are to be kept
floating.
.
.
The input pins of the module are not operator
accessible.
Figure 8. Output Ripple and Noise Test Setup.
Another SELV reliability test is conducted on the
whole system (combination of supply source and
subject module), as required by the safety
agencies, to verify that under a single fault,
hazardous voltages do not appear at the
module’s output.
Rdistribution Rcontact
Rcontact Rdistribution
Vin+
Vout+
RLOAD
Note: Do not ground either of the input pins of the
module without grounding one of the output
pins. This may allow a non-SELV voltage to
appear between the output pins and ground.
VO
VIN
Rdistribution Rcontact
Rcontact Rdistribution
Vin-
Vout-
The power module has extra-low voltage (ELV)
outputs when all inputs are ELV.
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.
All flammable materials used in the manufacturing of
these modules are rated 94V-0, or tested to the
UL60950 A.2 for reduced thickness.
For input voltages exceeding 60 Vdc but less than or
equal to 75 Vdc, these converters have been
evaluated to the applicable requirements of BASIC
INSULATION between secondary DC MAINS
DISTRIBUTION input (classified as TNV-2 in Europe)
and unearthed SELV outputs.
Figure 9. Output Voltage and Efficiency Test
Setup.
VO. IO
Efficiency
=
x
100 %
VIN. IIN
The input to these units is to be provided with a
maximum 5 A fast-acting fuse in the ungrounded lead.
LINEAGE POWER
6
LINEAGEPOWER [ LINEAGE POWER CORPORATION ]
