Data Sheet
October 5, 2009
KW0006-010 Series Power Modules:
36 – 75Vdc Input; 3.3 to 5.0Vdc Output; 6 to 10A Output Current
LINEAGE POWER 8
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.
ON/OFF
V
IN
(+)
V
IN
(-)
I
on/off
V
on/off
V
OUT
(+)
TRIM
V
OUT
(-)
Figure 16. Remote On/Off Implementation.
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 16). 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.
The typical open circuit V
on/off
generated by the module
is 3.4V. The I
ON/OFF
leakage current, through the switch,
is required to be less than 10uA otherwise the unit will
reach the threshold at which it switches.
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
(-).
Remote Sense
Remote sense minimizes the effects of distribution
losses by regulating the voltage at the remote-sense
connections (See Figure 17). The voltage between the
remote-sense pins and the output terminals must not
exceed the output voltage sense range given in the
Feature Specifications table:
[V
O
(+) – V
O
(–)] – [SENSE(+) – SENSE(–)] ≤ 10% V
O,Set
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 (Maximum rated power = V
o,set
x I
o,max
).
VO(+)
SENSE(+)
SENSE(–)
V
O(–)
V
I(+)
V
I(-)
IO
LOAD
CONTACT AND
DISTRIBUTION LOSS
SUPPLY
I
I
CONTACT
RESISTANCE
Figure 17. Circuit Configuration for remote
sense .
Input Under-Voltage Lockout
At input voltages below the input under-voltage lockout
limit, the module operation is disabled. The module will
only begin to operate once the input voltage is raised
above the undervoltage lockout turn-on threshold,
V
uv/on
.
Once operating, the module will continue to operate
until the input voltage is taken below the undervoltage
turn-off threshold, V
uv/off
.
Over-Temperature Protection
To provide protection under certain fault conditions, the
unit is equipped with a thermal shutdown circuit. The
unit will shutdown if the thermal reference test point
RT1 (Figure 19), exceeds 110
o
C (typical), but the
thermal shutdown is not intended as a guarantee that
the unit will survive temperatures beyond its rating. The
module will automatically restart upon cool-down to a
safe temperature.
Output Over-Voltage Protection
The output over-voltage protection scheme of the
modules has an independent over-voltage loop to
prevent single point of failure. This protection feature
latches-off the module in the event of over-voltage
across the output. Recycling the input voltage or
momentarily switching-off the module via the remote
on/off pin resets the latch.
The independent over-voltage loop has a relatively
slow response time. There are no precautions
necessary to meet the output over-voltage protection
limits for externally caused over-voltage conditions,
such as excessive remote sense or output trim
adjustments. However, special precautions are
necessary to insure the over-voltage limits are met
when the over-voltage is caused by internal module
control loop failure. Either a minimum of 660 µF
external output capacitance is required, or an external
