The Interpoint™ MSA Series™ and MGA Series™ of dc-dc
converters provide up to 5 watts of output power over the full
military temperature range with up to 76% efficiency. Thick-film
hybrid techniques provide military/aerospace reliability levels and
optimum miniaturization.
The converters are offered with standard screening, “ES”
screening, or fully compliant to “883” MIL-PRF-38534 Class H
screening. Standard microcircuit drawings (SMD) are available.
See “Table 12: Element Evaluation” on page 14 and “Table 13:
Environmental Screening” on page 15 for screening options
and descriptions.
The converters are switching regulators that use a flyback
converter design with a constant switching frequency of 550 kHz
typical. They are regulated, isolated units using a pulse width
modulated topology and are built as high reliability thick-film
hybrids. Isolation between input and output circuits is provided
with a transformer in the forward power path and an optical
link in the feedback control loop. Excellent input line transient
response and audio rejection is achieved by an advanced feed-
forward compensation technique. Negative output regulation is
maintained by tightly coupled magnetics. Up to 4 watts, 80% of
the total output power, is available from either output, provided
that the opposite output is simultaneously carrying 20% of the
total power in order to maintain the specified regulation on the
negative output. A predictable current limit is accomplished by
direct monitoring of the output load current, which results in a
constant current output. Internal input and output filters eliminate
the need for external capacitors for stable operation. Output filter
examples in “Figure 3: Low Noise Output Filter MSA and MGA
Single Output Models” on page 3 and “Figure 4: Low Noise
Output Filter MSA and MGA Dual Output Models” on page 3
provide suggested solutions for systems where very low output
ripple is required.
W
iDe
v
oltage
r
ange
C
onverter
D
esign
The MSA converters are designed to provide full power operation
over a full 16 to 40 VDC voltage range. Operation below 16 volts,
including MIL-STD-704E emergency power conditions is possible
with derated power. Low-line drop out graphs, “Figure 17” on
page 10 and “Figure 23” on page 11, graphs provide more
information.
The feed-forward compensation system rovides excellent
p
dynamic response and noise rejection. Audio rejection is typically
50 dB. The minimum to maximum step line transient response is
typically less than 1%.
i
mproveD
D
ynamiC
r
esponse
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 15
MSA_MGA Rev AC - 2013.06.13
Crane Aerospace & Electronics Power Solutions
MSA/MGA Single and Dual DC-DC Converters
28 Volt input – 5 WAtt
i
nhibit
F
unCtion
The inhibit feature can be used to disable internal switching and
inhibit the unit’s output. Inhibiting in this manner results in low
standby current and no generation of switching noise.
The converter is inhibited when the inhibit pin is pulled below
0.8 V and enabled when its inhibit pin is left floating. An external
inhibit interface should be capable of pulling the converter’s
inhibit pin below 0.8 V while sinking the maximum inhibit current
and also allowing the inhibit pin to float high to enable the
converter. A voltage should not be applied to the inhibit pin. The
open circuit output voltage associated with the inhibit pin is 9 to
11 V. In the inhibit mode, a maximum of 4 mA must be sunk from
the inhibit pin. See “Figure 2: Inhibit Interface MSA and MGA” on
page 3.
p
aCkaging
MSA - Down-leaded package
The MSA Series converters are packaged in hermetically sealed,
projection-welded metal cases which provide EMI/RFI shielding.
The small size, 1.075 x 1.075 x 0.270 inches (27.31 x 27.31 x
6.86 mm), saves space and weight in critical applications. See
“Figure 26: MSA Case Dimensions” on page 12.
MGA - Surface mount package
The surface mount MGA dc-dc converters can be mounted with
pick-and-place equipment or manually. See “Figure 28: MGA
Gull-Wing Solder Pad Layout” on page 13 for more information.
Internal components are soldered with SN96 (melting
temperature 221°C) to prevent damage during reflow. Maximum
reflow temperature for surface mounting the MGA converter is
220°C for a maximum of 30 seconds. SN60, 62, or 63 are the
recommended types of solder. Hand soldering should not exceed
300°C for 10 seconds per pin.
The hermetically sealed metal cases are available in two different
lead configurations. See “Figure 27: MGA Case Dimensions” on
page 13 and “Figure 28: MGA Gull-Wing Solder Pad Layout”
on page 13.
u
nDervoltage
l
oCkout anD
t
ransient
p
roteCtion
Undervoltage lockout helps keep system current levels low during
initialization or re-start operations. They can withstand short term
transients of up to 50 volts without damage. A low voltage lockout
feature keeps the converter shutdown below approximately 13
VDC to ensure smooth initialization.
mil-stD-461
Use our FMSA-461 (down-leaded) or our FMGA-461 (surface
mount) EMI filter to pass the CE03 requirements of
MIL-STD-461C.
Positive
Input
+
Positive
Output
Inhibit
PWM
Control
Error
Amp VR
Output
Common
+
Input
Common
Case
Ground
Isolated
Feedback
Negative
Output
= Dual Output
anD
F
igure
1: b
loCk
D
iagram
msa
www.craneae.com/interpoint
mga
Page 2 of 15
MSA_MGA Rev AC - 2013.06.13
Crane Aerospace & Electronics Power Solutions
MSA/MGA Single and Dual DC-DC Converters
28 Volt input – 5 WAtt
Positive
Input
12 k
5k
Inhibit
200 pF
10 K
3.9 K
2N3904
400
50 k
10V
Vcc
10 k
Input
Common
F
igure
2: i
nhibit
i
nterFaCe
msa
anD
mga
EMI Filter
Positive
Input
Input
Common
Positive
Positive
Input
Output
Case
Output Common
Input
Output
Common
Common
Case
C1
Positive
Output
T1
+
C2
C3 To Load
From input
power source
T1
The filter suggestions in Figure 3 and Figure 4
will further reduce the output ripple for systems
requiring very low output noise.
C1 = 0.27 µF ceramic capacitor, 500 V
C2 = C4 = 6.8 µF tantalum capacitor
C3 = C5 = 0.27 µF ceramic capacitor
Single output:
T1 = 15T #28 AWG winding on toroid, 5 m = 5000
F
igure
3: l
oW
n
oise
o
utput
F
ilter
msa
anD
mga s
ingle
o
utput
m
oDels
EMI Filter
From input
power source
Positive
Input
Positive
Output
Positive
Positive
Input
Output
Case
Output Common
Input
Common
Negative
Output
Case
C1
T2
C2+
C4+
C3
To Loads
Dual output:
T2 = 10T #28 AWG winding on toroid, 5 m = 5000
Input
Output
Common Common
C5
T2
F
igure
4: l
oW
n
oise
o
utput
F
ilter
msa
anD
mga D
ual
o
utput
m
oDels
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Page 3 of 15
MSA_MGA Rev AC - 2013.06.13
Crane Aerospace & Electronics Power Solutions
MSA/MGA Single and Dual DC-DC Converters
28 Volt input – 5 WAtt
pin
1
2
3
4
5
6
7
8
pin out Msa MoDels
single output
Positive Output
Output Common
No Connection
No Connection
Inhibit
Positive Input
Input Common
Case Ground
Dual output
Positive Output
Output Common
pin
1
2, 3
4
5, 6
7, 8
9, 10
11, 12
13
14
15, 16
17, 18
19, 20
pin out MGa MoDels
single output
Inhibit
Positive Input
No Connection
Input Common
Case Ground
No Connection
Positive Output
Positive Output
Output Common
Output Common
No Connection
Case Ground
Inhibit
Dual output
Positive Input
No Connection
Input Common
Case Ground
No Connection
Positive Output
Output Common
Output Common
Negative Output
No Connection
Case Ground
Negative Output
No Connection
Inhibit
Positive Input
Input Common
Case Ground
t
able
1: msa p
in
o
ut
To meet specified performance for the MGA, all pins must be
connected except “No Connection” pins and Inhibit pin.
t
able
3: mga p
in
o
ut
Squared corner and dot on top
of package indicate pin one.
1
2
3
4
5
BOTTOM VIEW
MSA
8
7
6
1
2
3
4
5
6
7
8
9
10
TOP VIEW
MGA
20
19
18
17
16
15
14
13
12
11
See “Figure 26: MSA Case Dimensions” on page 12.
Triangle in upper left corner of cover indicates pin one.
See “Figure 27: MGA Case Dimensions” on page 13.
∇
F
igure
5: msa p
in
o
ut
b
ottom
v
ieW
F
igure
6: mga p
in
o
ut
t
op
v
ieW
Inhibit
Msa pins not in use
Leave unconnected
Inhibit
MGa pins not in use
Leave unconnected
Connect to case ground for best
EMI performance.
not in
“No Connection” pin
Leave unconnected
not in
“No Connection” pins
t
able
2: msa p
ins
www.craneae.com/interpoint
u
se
Page 4 of 15
MSA_MGA Rev AC - 2013.06.13
t
able
4: mga p
ins
u
se
Crane Aerospace & Electronics Power Solutions
MSA/MGA Single and Dual DC-DC Converters
28 Volt input – 5 WAtt
S
tanDarD
M
iCrOCirCuit
D
rawing
(SMD)
5962-9309201HxC
5962-0251301HxC
5962-9309301HxC
5962-9309401HxC
5962-0052201HxC
5962-9308901HxC
5962-9309001HxC
sMD nuMbers
MSa S
iMilar
p
art
S
tanDarD
M
iCrOCirCuit
D
rawing
(SMD)
5962-9309201HZC
5962-9309301HZC
5962-9309401HZC
5962-0052201HZC
5962-9308901HZC
5962-9309001HZC
sMD nuMbers
Mga S
iMilar
p
art
MSA2805S/883
MSA285R2S/883
MSA2812S/883
MSA2815S/883
MSA2805D/883
MSA2812D/883
MSA2815D/883
MGA2805SZ/883
MGA2812SZ/883
MGA2815SZ/883
MGA2805DZ/883
MGA2812DZ/883
MGA2815DZ/883
For exact specifications for an SMD product, refer to
the SMD drawing. SMDs can be downloaded from:
http://www.landandmaritime.dla.mil/programs/smcr
t
able
5: msa smD n
umbers
For exact specifications for an SMD product, refer
to the SMD drawing. SMD numbers are shown for
the surface mount gull-wing case. For the straight-
lead case, replace the Z (HZC) in the SMD with a Y
(HYC). SMDs can be downloaded from: http://www.
landandmaritime.dla.mil/programs/smcr
t
able
6: mga smD n
umbers
MoDel nuMberinG key
Base Model
MSA
28 12
Input Voltage
Output Voltage
(R = decimal point, 5R2 = 5.2 Vout)
Number of Outputs
(S = single, D = dual)
MoDel nuMberinG key
Base Model
Input Voltage
MGA
28 12 S
Z / 883
D / 883
Output Voltage
Number of Outputs
(S = single, D = dual)
Gull Wing Lead Option
(Straight leaded case has no designator
in this position.)
Screening
(Standard screening has no designator
in this position.)
Screening
(Standard screening has no designator
in this position.)
F
igure
7: msa m
oDel
n
umbering
k
ey
F
igure
8: mga m
oDel
n
umbering
k
ey
t
O
cateGory
DeterMine the MODel nuMber enter One OptiOn frOM eaCh CategOry in the fOrM belOw
.
base Model and
input Voltage
MSA
MGA
output Voltage
1
05, 5R2, 12, 15
05, 12, 15
number of
outputs
2
S
D
case options
3
MSA – down-leaded: leave blank
MGA – straight leads: leave blank
MGA – gull wings: Z
__________
M A
__________
/
screening
4
(standard, leave blank)
ES
883
MoDel nuMber options
options
Fill in For
MoDel #
Notes:
1. 5R2 is a 5.2 output model.
2. Number of Outputs: S is a single output and D is a dual output
3. Case Options: For the MSA down-leaded case leave the case option blank. For the MGA straight-lead case, leave the case option blank. For the MGA, surface mount
gull-wing case, insert the letter “Z” in the case option position.
4. Screening: For standard screening leave the screening option blank. For other screening options, insert the desired screening level. For more information see
“Table 11: Element Evaluation” on page 12 and “Table 12: Environmental Screening” on page 13.
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