GE Industrial Solutions JNC350R Series - Manual (Page 7)

Data Sheet
August 9, 2010
JNC350R Power Modules; DC-DC Converters
18 – 36 Vdc Input; 28Vdc Output; 350W Output
LINEAGE POWER 7
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 (V
on/off
) between the ON/OFF
terminal and the V
IN
(-) terminal (see Figure 10). Logic
low is 0V ≤ V
on/off
≤ 1.2V. The maximum I
on/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 V
on/off
generated by the module is 5V, and the maximum
allowable leakage current at V
on/off
= 5V is 50μA.
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 V
IN
(-).
Figure 10. Circuit configuration for using Remote
On/Off Implementation.
Over-Current Protection (OCP)
To provide protection in a fault output overload
condition, the module is equipped with internal current
limiting protection circuitry, and can endure over-
current transient overloads depending upon the
duration and amplitude of the overload. An internal
buffer measures the relative product of the duration
and amplitude of the overload and allows operation
until a limit threshold is
reached. For lower amplitude
overloads, the module will operate without shutdown
for a longer transient overload. If the overload
amplitude is larger, the module will reach shutdown in
a shorter period of time.
A latching shutdown option is standard. If over-current
persists for beyond the overload buffer, the module
will shut down and remain off until the module is reset
by either cycling the input power or by toggling the
on/off pin for one second.
An OCP auto-restart option (code = 3 or 4, see Table
2) is also available in a case where an auto recovery
is required. If over-current 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 over-current condition is
corrected.
Over-Voltage Protection (OVP)
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 OVP auto-restart option (code = 3, see Table 2) is
also available in a case where an auto recovery is
required. Once the module has shutdown, after a
period of approximately 4.5 seconds, the module will
restart. If the output overload condition still exists
when the module restarts, it will shut down again. This
operation will continue indefinitely, until the over-
current condition is corrected.
Remote sense
Remote sense minimizes the effects of distribution
losses by regulating the voltage at the remote-sense
connection (see Figure 11). For No Trim or Trim down
application, the voltage between the remote-sense pin
and the output terminal must not exceed the output
voltage sense range given in the Feature
Specifications table i.e.: SENSE(+)–Vo(+) ≤2% V
o,nom
.
The voltage between the Vo(+) and Vo(-) terminals
must not exceed the minimum output overvoltage
shut-down value indicated in the Feature
Specifications table. This limit includes any increase
in voltage due to remote-sense compensation and
output voltage set-point adjustment (trim). See Figure
11. Do not connect SENSE(-) to the Vo(-) or Rload(-)
as there is a 0Ω connection internal to the module. If
not using the remote-sense feature to regulate the
output at the point of load, then connect SENSE(+) to
Vo(+).
Although the output voltage can be increased by both
the remote sense and by the trim, the maximum
increase for the output voltage is not the sum of both.
The maximum increase is the larger of either the
remote sense or the trim. The amount of power
delivered by the module is defined as the voltage at
the output terminals multiplied by the output current.
When using remote sense and trim: the output
voltage of the module can be increased, which at the
same output current would increase the power output
of the module. Care should be taken to ensure that
the maximum output power of the module remains at
or below the maximum rated power.