JFW100F Lineage Power, JFW100F Datasheet - Page 15

• Manufacturer Part Number: JFW100F
• Manufacturer: Lineage Power

April 2008
Feature Descriptions
Forced Load Sharing (Parallel Operation)
(continued)
Figure 26. Wiring Configuration for Redundant
Output Current Monitor
The current monitor (CURMON) pin produces a dc volt-
age proportional to the dc output current of the module.
The voltage is referenced to the secondary SENSE(–)
pin and is typically 4.10 V at rated output current. For
paralleling with FW300x modules, consult the factory
for the V/A ratio. The output impedance of this pin is
approximately 20 k¾, so customer detection circuitry
must have a high-impedance input.
Overtemperature Protection
These modules feature an overtemperature protection
circuit to safeguard against thermal damage. The cir-
cuit shuts down and latches off the module when the
maximum case temperature is exceeded. The module
can be restarted by cycling the dc input power for at
least 1.0 second or by toggling the primary or second-
ary referenced remote on/off signal for at least
1.0 second.
Lineage Power
Parallel Operation
CASE
ON/OFF
V
V
CASE
ON/OFF
V
V
I
I
I
I
(+)
(–)
(+)
(–)
PARALLEL
PARALLEL
SENSE(+)
SENSE(–)
SENSE(+)
SENSE(–)
V
V
V
V
O
O
O
O
dc-dc Converters; 36 to 75 Vdc Input; 3.3 Vdc Output; 33 W to 99 W
(+)
(–)
(+)
(–)
(continued)
8-581 (C).c
Power Good Signal
The power good signal (PWRGOOD pin) is an open-
collector, secondary-referenced pin that is pulled low
when all five of the following conditions are met:
1. The sensed output voltage is greater than half the
2. The overvoltage shutdown latch is not set.
3. The thermal shutdown latch is not set.
4. The unit is not in current limit.
5. Secondary internal bias is present.
There is one situation where the power good signal can
be low even though the module has failed. This can
occur when the module is paralleled with other mod-
ules for additional output power (i.e., the output ORing
diodes would not be used). If one module power train
stops delivering power (fails), the other paralleled mod-
ule(s) would provide a voltage at the output pin of the
failed module. The failed module would then not detect
that its output power is not being delivered. However, in
this situation, the current monitor pins of the paralleled
modules would indicate that current is not being deliv-
ered from one module and that module had failed.
For redundant applications, the ORing diodes would
keep the other module voltages from being applied to
the failed module output and the power good signal
would indicate a failure.
Thermal Warning Signal
The thermal warning (TEMPWARN) pin is a second-
ary-referenced, open-collector output that shorts to
SENSE(–) a few degrees before the module goes into
thermal shutdown.
When the module temperature cools, the thermal warn-
ing pin will open, but the unit will remain latched off until
the input power or the primary or secondary referenced
remote on/off is recycled for 1.0 second.
rated nominal output voltage.
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