Data Sheet
April 3, 2012
JRCW450R Power Modules; DC-DC Converters
36 – 75 Vdc Input; 32Vdc Output; 450W Output
LINEAGE POWER 7
Safety Considerations (continued)
For all input sources, other than DC MAINS, where the
input voltage is between 60 and 75V dc (Classified as
TNV-2 in Europe), the following must be meet, if the
converter’s output is to be evaluated for SELV:
The input source is to be provided with reinforced
insulation from any hazardous voltage, including
the ac mains.
One Vi pin and one Vo pin are to be reliably
earthed, or both the input and output pins are to be
kept floating.
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.
All flammable materials used in the manufacturing of
these modules are rated 94V-0, or tested to the
UL60950 A.2 for reduced thickness.
The input to these units is to be provided with a
maximum 25 A fast-acting or time-delay fuse in the
ungrounded input connection.
Feature Description
Remote On/Off
Two remote on/off options are available. Positive logic
turns the module on during a logic high voltage on the
ON/OFF pin, and off during a logic low. Negative logic
remote On/Off, device code suffix “1”, 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 (open collector or equivalent) to control
the voltage (Von/off) between the ON/OFF terminal and
the VIN(-) terminal (see Figure 10). Logic low is
0V Von/off 1.2V. The maximum Ion/off during a logic
low is 1mA, the switch should be maintain a logic low
level whilst sinking this current.
During a logic high, the typical maximum Von/off
generated by the module is 5V, and the maximum
allowable leakage current at Von/off = 5V is 50A.
If not using the remote on/off feature:
For positive logic, leave the ON/OFF pin open.
For negative logic, short the ON/OFF pin to VIN(-).
Figure 10. Circuit configuration for using Remote
On/Off Implementation.
Overcurrent Protection
To provide protection in a fault output overload
condition, the module is equipped with internal current
limiting protection circuitry, and can endure continuous
overcurrent by providing constant current output, for up
to 4 seconds, as long as the output voltage is greater
than VtrimMIN. If the load resistance is to low to support
VtrimMIN in an overcurrent condition or a short circuit load
condition exists, the module will shutdown immediately.
A latching shutdown option is standard. Following
shutdown, the module will remain off until the module is
reset by either cycling the input power or by toggling
the on/off pin for one second.
An auto-restart option (4) is also available in a case
where an auto recovery is required. If overcurrent
greater than 19A persists for few milli-seconds, the
module will shut down and auto restart until the fault
condition is corrected. If the output overload condition
still exists when the module restarts, it will shut down
again. This operation will continue indefinitely, until the
overcurrent condition is corrected.
Over Voltage Protection
The output overvoltage protection consists of circuitry
that monitors the voltage on the output terminals. If the
voltage on the output terminals exceeds the over
voltage protection threshold, then the module will
shutdown and latch off. The overvoltage latch is reset
by either cycling the input power for one second or by
toggling the on/off signal for one second. The
protection mechanism is such that the unit can continue
in this condition until the fault is cleared.
An auto-restart option (4) is also available in a case
where an auto recovery is required.