1010 Lineage Power
Data Sheet
April 2008
dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 50 W to 150 W
JW050C, JW075C, JW100C, JW150C Power Modules:
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 tai-
lout 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 ON/OFF pin, and off during a logic low.
Negative logic remote on/off turns the module off dur-
ing a logic high and on during a logic low. Negative
logic (code suffix “1”) is the factory-preferred configura-
tion.
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 VI(–) terminal (Von/off). The
switch can be an open collector or equivalent (see
Figure 20). A logic low is Von/off = 0 V to 1.2 V. The
maximum Ion/off during a logic low is 1 mA. The switch
should maintain a logic-low voltage while sinking 1 mA.
During a logic high, the maximum Von/off generated by
the power module is 15 V. The maximum allowable
leakage current of the switch at Von/off = 15 V is 50 µA.
If not using the remote on/off feature, do one of the
following:
nFor negative logic, short ON/OFF pin to VI(–).
nFor positive logic, leave ON/OFF pin open.
SENSE(+)
V
O
(+)
SENSE(–)
V
O
(–)
V
I
(–)
I
on/off
ON/OFF
V
I
(+)
LOAD
V
on/off
8-720 (C).c
Figure 20. Remote On/Off Implementation
Remote Sense
Remote sense minimizes the effects of distribution
losses by regulating the voltage at the remote-sense
connections. The voltage between the remote-sense
pins and the output terminals must not exceed the out-
put voltage sense range given in the Feature Specifica-
tions table, i.e.:
[VO(+) – VO(–)] – [SENSE(+) – SENSE(–)] ð 0.5 V
The voltage between the VO(+) and VO(–) terminals
must not exceed 15.5 V. This limit includes any
increase in voltage due to remote-sense compensation
and output voltage set-point adjustment (trim). See Fig-
ure 21.
If not using the remote-sense feature to regulate the
output at the point of load, then connect SENSE(+) to
VO(+) and SENSE(–) to VO(–) at the module.
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. Consult the factory if you
need to increase the output voltage more than the
above limitation.
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.
V
O
(+)
SENSE(+)
SENSE(–)
V
O
(–)
V
I
(+)
V
I
(–)
I
O
LOAD
CONTACT AND
DISTRIBUTION LOSSES
SUPPLY I
I
CONTACT
RESISTANCE
8-651 (C).m
Figure 21. Effective Circuit Configuration for
Single-Module Remote-Sense Operation