LW025F871 Lineage Power, LW025F871 Datasheet - Page 8

• Manufacturer Part Number: LW025F871
• Description: CONVERTER DC/DC 3.3V 16.5W OUT
• Manufacturer: Lineage Power
• Series: LW025r
• Type: Isolated with Remote On/Offr

Specifications of LW025F871

• Output: 3.3V
• Number Of Outputs: 1
• Power (watts): 25W
• Mounting Type: Through Hole
• Voltage - Input: 36 ~ 75V
• Package / Case: 8-DIP Module
• 1st Output: 3.3 VDC @ 5A
• Size / Dimension: 2.00" L x 2.00" W x 0.39" H (50.8mm x 50.8mm x 9.9mm)
• Power (watts) - Rated: 16.5W
• Operating Temperature: -40°C ~ 110°C
• Efficiency: 77%
• Approvals: CE, CSA, UL, VDE
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• 3rd Output: -
• 2nd Output: -
• 4th Output: -

36 Vdc to 75 Vdc Inputs; 25 W
Design Considerations
Grounding Considerations
For modules without the isolated case ground pin
option, the case is internally connected to the V
For modules with the isolated case ground pin, device
code suffix “7,” the V
case.
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 10, a 33 µF
electrolytic capacitor (ESR < 0.7 ¾ 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.
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., UL 1950, CSA C22.2 No. 950-95, and VDE 0805
(EN60950, IEC950).
If the input source is non-SELV (ELV or a hazardous
voltage greater than 60 Vdc and less than or equal to
75 Vdc), for the module's output to be considered
meeting the requirements of safety extra-low voltage
(SELV), all of the following must be true:
n
n
n
n
8 8
The input source is to be provided with reinforced
insulation from any other hazardous voltages, includ-
ing the ac mains; and
One V
both the input and output pins are to be kept floating;
and
The input pins of the module are not operator acces-
sible; and
Another SELV reliability test is conducted on the
whole system, as required by the safety agencies, on
the combination of supply source and the subject
module to verify that under a single fault, hazardous
voltages do not appear at the module's output.
I
pin and one V
I
(+) pin is not connected to the
O
pin are to be grounded or
I
(+) pin.
Note: Do not ground either of the input pins of the
The power module has extra-low voltage (ELV) outputs
when all inputs are ELV.
The input to these units is to be provided with a maxi-
mum 5 A normal-blow fuse in the ungrounded lead.
Feature Descriptions
Overcurrent Protection
To provide protection in a fault (output overload) condi-
tion, the unit is equipped with internal current-limiting
circuitry and can endure current limiting for an unlim-
ited duration. At the point of current-limit inception, the
unit shifts from voltage control to current control. If the
output voltage is pulled very low during a severe fault,
the current-limit circuit can exhibit either foldback or
tailout characteristics (output-current decrease or
increase). The unit operates normally once the output
current is brought back into its specified range.
Remote On/Off
Two remote on/off options are available. Positive logic
remote on/off turns the module on during a logic-high
voltage on the REMOTE ON/OFF pin, and off during a
logic low. Negative logic, device code suffix “1,” remote
on/off turns the module off during a logic high and on
during a logic low.
To turn the power module on and off, the user must
supply a switch to control the voltage between the
on/off terminal and the V
switch can be an open collector or equivalent (see Fig-
ure 13). A logic low is V
imum I
should maintain a logic-low voltage while sinking 1 mA.
During a logic high, the maximum V
the power module is 6 V. The maximum allowable leak-
age current of the switch at V
The module has internal capacitance to reduce noise
at the ON/OFF pin. Additional capacitance is not gen-
erally needed and may degrade the start-up character-
istics of the module.
on/off
module without grounding one of the output
pins. This may allow a non-SELV voltage to
appear between the output pins and ground.
during a logic low is 1 mA. The switch
on/off
I
(–) terminal (V
= –0.7 V to 1.2 V. The max-
on/off
= 6 V is 50 µA.
on/off
on/off
Lineage Power
generated by
April 2008
). The