JW030-Series Power Modules:
Lineage Power36 Vdc to 75 Vdc Inputs; 30 W
Data Sheet
March 26, 2008
Feature Descriptions
Overcurrent Protection
VI(+)
VI(-)
–
Von/off
SENSE(+)
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.
VO(+)
VO(–)
+
LOAD
REMOTE
ON/OFF
Ion/off
SENSE(–)
8-720(C).h
Figure 23. Remote On/Off Implementation
Remote Sense
Remote On/Off
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.:
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 remote on/off turns the module
off during a logic high and on during a logic low. Nega-
tive logic, device code suffix “1,” is the factory-preferred
configuration.
[VO(+) – VO(–)] – [SENSE(+) – SENSE(–)] ð 0.2 V
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 Fig-
ure 23). A logic low is Von/off = –0.7 V to 1.2 V, during
which the module is off. The maximum Ion/off during a
logic low is 1 mA. The switch should maintain a logic-
low voltage while sinking 1 mA.
The voltage between the VO(+) and VO(–) terminals
must not exceed the minimum output overvoltage shut-
down voltage as 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 24.
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.
During a logic high, the maximum Von/off generated by
the power module is 6 V. The maximum allowable leak-
age current of the switch at Von/off = 6 V is 50 µA.
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.
SENSE(+)
SENSE(–)
VI(+)
VI(-)
VO(+)
VO(–)
IO
SUPPLY
LOAD
CAUTION: To avoid damaging the power module
or external on/off circuit, the connec-
tion between the VI(–) pin and the input
source must be made before or simulta-
neously to making a connection
II
CONTACT
RESISTANCE
CONTACT AND
DISTRIBUTION LOSSES
8-651(C).m
Figure 24. Effective Circuit Configuration for
between the ON/OFF pin and the input
source (either directly or through the
external on/off circuit.)
Single-Module Remote-Sense Operation
12
Lineage Power