Crane Aerospace & Electronics Power Solutions
LCM-120 Line Conditioning Module
28 Volt input – 120 watt
Features
powers dc-dc converters requiring 28 Vin
input voltage 12 to 50 Vdc
•
Operating temperature -55° to +125°C
•
Works through transients of
up to 80 V for up to 120 ms
•
Synchronization function
•
Undervoltage lockout
•
Inhibit function
MODELS
VDC Output
LCM-120
24 to 36 VDC
description
The LCM-120™ line conditioning module is a non-isolated dc-dc
converter used to extend the input voltage range of Interpoint’s
dc-dc converters. The LCM-120 delivers up to 120 watts of
throughput power from a 12 to 50 volt dc source in one of three
modes:
•
12 to 24 volts input – internal boost converter
delivers 24 V
•
24 to 36 volts input – input is connected
directly to output
pulled up with a resistor. The sync input allows synchronization of
the LCM-120 module’s internal clock to an external pulse source
with LSTTL level voltages and a 40% to 60% duty cycle. When
unused, the sync should be left unconnected. The power fail flag
output is a fully isolated NPN opto-coupler transistor rated to 18
volts dc. It will drive an external LSTTL load low if the LCM-120
module’s input voltage drops below 10 volts dc and will remain
active until the module output voltage also drops below 10 volts
dc.
•
36 to 50 volts input – internal buck converter
delivers 36 V
L
ow
v
in
anD
H
eavy
L
oaDs
C
onverter
D
esign
The LCM-120 module is protected by internal current limit
circuitry which limits current according to input voltage. This
feature also allows safe charging of large external capacitors.
Because current is sensed between input common and output
common there is normally no external connection made between
these pins. (Note: If an external connection between input
and output common is desired, the resistance of this external
connection must be greater than 1 ohm.) The LCM module will
work through up to an 80 volt transient for up to 120 milliseconds
while holding the output at 36 VDC.
When the LCM-120 module is operated at 12 volts in and 120
watts output, line loss can become a major concern. The module
will output 24 volts at 120 watts. Allowing for efficiency, the input
current will be 120 watts / 0.88 / 12 = 11.36 A. If the resistance in
the line from the power source to the LCM-120 is 0.05 ohms, the
line loss at 12 volts from the power source will be (0.05 • 11.36)
= 0.57 volts. The LCM-120 module will see 11.43 volts and will
not start up.
e
xternaL
C
apaCitanCe
F
eatures
Features include an under voltage lockout, an inhibit input, a
synchronization input and a power fail flag output. Under voltage
lockout prevents start-up for inputs less than 12 volts dc and will
shut down the converter for an input of less than 10 volts dc. The
inhibit input, when connected to input common, disables the
internal converter and opens the output power path while leaving
the power fail flag unaffected. Inhibit is normally left open or
Interpoint recommends a minimum output capacitance of 330 uF
and a total ESR of at least 0.25 ohms to ensure stability of the
LCM-120 module’s boost converter. For very low ESR capacitors,
an external series resistor (non-inductive) may be used to
obtain the minimum total ESR. The maximum recommended
capacitance is 1 F.
Crane Aerospace & Electronics
Power Solutions – Interpoint Products
10301 Willows Rd. NE, Redmond, WA 98052
+1.425.882.3100 • power@crane-eg.com
www.craneae.com/interpoint
Page 1 of 7
LCM-120 Rev AA - 2013.06.14
Crane Aerospace & Electronics Power Solutions
LCM-120 Line Conditioning Module
28 VoLt input – 120 watt
pin
1
2
3
4
5
6
7
8
9
10
11
12
LcM-120
pin out
ModeL nuMbering key
Output Power
Base Model
LCM – 120 / ES
Positive Input
Positive Input
Input Common
Input Common
Output Common
Positive Output
No Connection
No Connection
Power Fail Flag Return
Power Fail Flag Output
Inhibit
Sync
t
aBLe
1: o
utput
v
oLtage
Screening
(Standard screening has no
designator in this position.)
Note: There is only one LCM-120 model.
F
igure
4: m
oDeL
n
umBering
k
ey
Angled corner indicates pin one.
T
o deTermine The model number enTer one
category
options
FiLL in For
ModeL #
opTion from each caTegory in The form
below
.
base Model
screening
1
ModeL nuMber options
1
2
3
4
5
6
12
11
TOP VIEW
LCM-120
(Pin side, marked side)
10
9
8
7
LCM-120
__________
LCM-120
(standard, leave blank)
ES
/
See “Figure 5: Case U” on page 6 for dimensions.
F
igure
3: p
in
o
ut
Notes:
1. Screening: For standard screening leave the screening option blank.
For other screening options, insert the desired screening level. For more
information see “Table 6: Environmental Screening” on page 7.
t
aBLe
3: m
oDeL
n
umBer
o
ptions
Inhibit
Sync
pins not in use
Leave unconnected
Leave unconnected
Leave unconnected
“No Connection” pin
t
aBLe
2: p
ins
n
ot in
u
se
www.craneae.com/interpoint
Page 3 of 7
LCM-120 Rev AA - 2013.06.14
Crane Aerospace & Electronics Power Solutions
LCM-120 Line Conditioning Module
28 VoLt input – 120 watt
t
aBLe
4: o
perating
C
onDitions
25°C
Case
, 28 vDC v
in
,
unLess otHerwise speCiFieD
.
MODELS HEAD
PARAMETER
LEAD SOLDERINg TEMPERATURE
STORAgE TEMPERATURE
CASE OPERATINg
TEMPERATURE
1
1
1
CONDITIONS
10 seconds max.
FULL POWER
1
MIN
—
-65
-55
-55
TYP
—
—
—
—
MAX
300
+150
+125
+135
UNITS
°C
°C
°C
ABSOLUTE
LINEARLY
@ 500 VDC AT 25°C
FREE RUN
-55° TO +125°C
INPUT FREQUENCY
DUTY CYCLE
ACTIVE LOW
ACTIVE HIgH
REFERENCED TO
IF NOT USED
DERATINg OUTPUT POWER/CURRENT
ISOLATION, ANY PIN TO CASE
EXCEPT CASE PIN
CONVERSION FREQUENCY
SYNCHRONIZATION
1
From 100% at 125°C to 0% at 135°C
100
—
550
40
—
4.5
—
600
—
—
—
—
—
—
600
60
0.8
–
Megohms
kHz
kHz
%
VDC
INPUT COMMON
1
LEAVE UNCONNECTED
—
—
1.3
VDC
INPUT COMMON
OPEN COLLECTOR OR
UNCONNECTED
—
10
—
V
INHIBIT ACTIVE LOW (OUTPUT DISABLED)
Do not apply a voltage to the inhibit pin
INHIBIT ACTIVE HIgH (OUTPUT ENABLED)
Do not apply a voltage to the inhibit pin
INHIBIT PIN PULLED LOW
REFERENCED TO
INHIBIT PIN CONDITION
OPEN PIN VOLTAgE
1
Notes
1. guaranteed by design. Not an in-line test.
www.craneae.com/interpoint
Page 4 of 7
LCM-120 Rev AA - 2013.06.14