Hi-Rel DC/DC CONVERTER
MGDM-150 : 150W POWER
• Ultra wide input range 16-80 Vdc, 9-45 Vdc
• 28Vdc input compliant with MIL-STD-704A/D/F
• Industry standard half brick package
• Power up to 150 W
• Wide temperature range : -40/+105°C baseplate
• High efficiency (typ. 86%-90%)
• Soft start
• Galvanic isolation 1 500 VDC
• Integrated LC EMI filter
• Synchronizable
• Load sharing, N+1 redundancy
• No load to full load operation
• Fully protected by independant security
• Under & overvoltage lock-out
• Overvoltage protection
• Current limitation protection
• Over temperature protection
• No optocoupler for high reliability
• Leaded process
Gaia Converter FC02-009.12/13 Revision RS
©
REDEFINING THE SOURCE OF POWER
1-General
5:1 Low Input Voltage : 9-45 & 16-80 VDC
Single Output
Metallic case - 1 500 VDC Isolation
Hi-Rel
Grade
For locations, phone, fax, E-Mail see back cover
4
The MGDM-150 low input voltage series is a
complete line of high density wide input range
DC/DC power modules designed for aerospace,
military and high-end industrial applications. These
modules use a patented fixed switching topology
at 420 KHz providing ultra wide input range, low
noise characteristics and high power density. Stan-
dard models are available with ultra wide input
voltage range of 9-45, 16-80 volts. The series
include single output voltage choices of 3,3, 5,
12, 15, 24, 28 volts.
The MGDM-150 low input voltage series include
synchronization load sharing, trim and sense
functions.
The synchronization function allows to synchronize
more than one converter to one frequency or an
external source frequency. The load sharing allows
parallel operation to increase power with a true
N+1.
All the modules are designed with LC network
filters to minimize reflected input current ripple
and output voltage ripple.
The modules have totally independant security
functions including input undervoltage and
overvoltage lock-out, output overvoltage protec-
tion, output current limitation protection, and
temperature protection. Additionnally a soft-start
function allows current limitation and eliminates
inrush current during start-up.
The design has been carried out with surface
mount components, planar transformer and is
manufactured in a fully automated process to
guarantee high quality. The modules are potted
with a bi-component thermal conductive
compound and used an insulated metallic
substrate to ensure optimum power dissipation
under harsh environmental conditions.
2-Product Selection
Input Voltage Range
B : 3.3 VDC
C : 5 VDC
E : 12 VDC
F : 15 VDC
I : 24 VDC
J : 28 VDC
Permanent
H : 9-45 VDC
O : 16-80 VDC
Output
Single output model : MGDS - 150 - input output option suffix
/
Options : Suffix :
/T : option for -55°C start up operating temperature
/S : option for screening and serialization -L : leaded process
For locations, phone, fax, E-Mail see back cover
2
Hi-Rel
Grade
MGDM-150 Low Input Series
Gaia Converter FC02-009.12/13 Revision S
©
4
2- Product Selection (continued)
Current
30 A
25 A
12,5 A
10 A
6,25 A
5,35 A
30 A
30 A
12,5 A
10 A
6,25 A
5,35 A
Reference
MGDS-150-H-B
MGDS-150-H-C
MGDS-150-H-E
MGDS-150-H-F
MGDS-150-H-I
MGDS-150-H-J
MGDS-150-O-B
MGDS-150-O-C
MGDS-150-O-E
MGDS-150-O-F
MGDS-150-O-I
MGDS-150-O-J
Output
3.3 VDC
5 VDC
12 VDC
15 VDC
24 VDC
28 VDC
3.3 VDC
5 VDC
12 VDC
15 VDC
24 VDC
28 VDC
Input range
9-45 VDC
9-45 VDC
9-45 VDC
9-45 VDC
9-45 VDC
9-45 VDC
16-80 VDC
16-80 VDC
16-80 VDC
16-80 VDC
16-80 VDC
16-80 VDC
Options
/T , /S
/T , /S
/T , /S
/T , /S
/T , /S
/T , /S
/T , /S
/T , /S
/T , /S
/T , /S
/T , /S
/T , /S
Suffix
-L
-L
-L
-L
-L
-L
-L
-L
-L
-L
-L
-L
Converter Selection Chart
MGDS - 150 - O - C / T - L
Number of Outputs :
S : single output
Input voltage range :
H : 9-45 VDC
O : 16-80 VDC
Output voltage :
See table page 1
Option :
/T : -55°C start up operation
/S : screening & serialization
(consult application note
«screening grades»)
Suffix :
-L : Leaded process
For locations, phone, fax, E-Mail see back cover
3
Hi-Rel
Grade
MGDM-150 Low Input Series
Gaia Converter FC02-009.12/13 Revision S
©
4
3- Block Diagram
The MGDM-150 low input series DC/DC converter is
based on a constant 420KHz pulse-width modulated
forward topology designed for ultra large input
range.
The output voltage is monitored on the secondary
side avoiding the use of optocoupler to optimize
long-term reliability and provide good immunity
against radiations.
An auxilliary supply is implemented to feed
independently all security functions such as the input
undervoltage lock-out (UVLO), overvoltage lock-out
(OVLO), the output overload protection (OCP), the
output overvoltage protection (OVP) and the ther-
mal protection (OTP).
As this auxilliary power is independent from the main
power supply, the module features an extreme wide
trim windows from 10% to 110% of the nominal
output voltage.
The main power transformer designed for more than
150W power is a multi-layer planar transformer which
allows 100% reproductibility for optized module
efficiencies.
The controlled feedback regulation is located at the
secondary side allowing a high regulation bandwidth
and a very fast response to load changes.
For locations, phone, fax, E-Mail see back cover
4
Hi-Rel
Grade
MGDM-150 Low Input Series
Gaia Converter FC02-009.12/13 Revision S
©
4
Note * : These performances are measured with the sense line connected..
Note ** : It is recommended to mount the converter on a heatsink for this test, see section 10-3 and 10-9 for further details.
Note *** : The ripple output voltage is the periodic AC component imposed on the output voltage, an aperiodic and random component (noise) has also to be considered.
This noise can be reduced by adding 4 external decoupling capacitors connected between inputs and case and between outputs and case. These capacitance should
be layed-out as close as possible from the converter. Please refer to page 8 for more details.
4- Electrical Specifications
Data are valid at +25°C, unless otherwise specified.
Parameter Conditions Limit or
typical Units Single Output MGDS-150
150 - H 150 - O
Input
Nominal input voltage Full temperature range Nominal VDC 24 28
Permanent input
voltage range (Ui) Full temperature range Min. - Max. VDC 9 - 45 16 - 80
Input surge withstand Above OVLO converter
Turns - off Maximum VDC/min. 50/1 100/1
Undervoltage lock-out
(UVLO)
Turn-on voltage
Turn-off voltage
Nominal
Nominal
VDC
VDC
8,5
7,5
15,5
14,5
Overvoltage lock-out
(OVLO)
Turn-on voltage
Turn-off voltage
Nominal
Nominal
VDC
VDC
45
46
80
81
Start up time
Ui nominal
Nominal output
Full load : resistive
Maximum ms 30 30
Reflected ripple current Ui nominal, full load
BW = 20MHz Maximum mApp 200 500
Input current in short
circuit
mode (Average)
Ui nominal
Short-circuit Typical A 1 1
No load input current Ui nominal
No load Maximum mA 30 30
Input current in inhibit
mode
Ui nominal
Inhibit Maximum mA 15 15
Output
Output voltage * Ui min. to max.
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
VDC
VDC
VDC
VDC
VDC
VDC
3,3
5
12
15
24
28
3,3
5
12
15
24
28
Set Point accuracy * Ambient temperature : +25°c
Ui nominal, 75% load Maximum % +/- 2 +/- 2
Output power ** At 105°c baseplate
Ui min. to max. Maximum W 100 to 150 100 to 150
Output current **
3,3V output
5V output
12V output
15V output
24V output
28V output
Full temperature range
Ui min. to max.
Maximum
Maximum
Maximum
Maximum
Maximum
Maximum
A
A
A
A
A
A
30
25
12,5
10
6,25
5,35
30
30
12,5
10
6,25
5,35
Ripple output voltage ***
3,3V and 5V output
12V output
15V output
24V and 28V output
Ui nominal
Full load
BW = 20MHz
Typical
Typical
Typical
Typical
mVpp
mVpp
mVpp
mVpp
50
100
150
250
50
100
150
250
Output regulation *
(Line + load + thermal)
Ui min. to max.
0% to full load Maximum % +/- 1 +/- 1
Output Voltage Trim As function of output voltage Minimum
Maximum
%
%
10 **
110
10 **
110
Efficiency Ui nominal
Full load Typical % see curves page 5 and 6
For locations, phone, fax, E-Mail see back cover
5
Hi-Rel
Grade
MGDM-150 Low Input Series
Gaia Converter FC02-009.12/13 Revision S
©
4
4- Electrical Characteristics (continued)
10 20 30 40 50 60 70 80 90 100
50,00%
55,00%
60,00%
65,00%
70,00%
75,00%
80,00%
85,00%
MGDS-150-H-B - Efficiency vs Output Power
Vin=9V
Vin=24V
Vin=45V
Pout(W)
10 30 50 70 90 110
50,00%
55,00%
60,00%
65,00%
70,00%
75,00%
80,00%
85,00%
90,00%
MGDS-150-H-C - Efficiency vs Output Power
Vin=9V
Vin=24V
Vin=45V
Pout(W)
10 30 50 70 90 110 130 150
50,00%
55,00%
60,00%
65,00%
70,00%
75,00%
80,00%
85,00%
90,00%
MGDS-150-H-E - Efficiency vs Output Power
Vin=9V
Vin=24V
Vin=45V
Pout(W)
10 30 50 70 90 110 130 150
50,00%
55,00%
60,00%
65,00%
70,00%
75,00%
80,00%
85,00%
90,00%
MGDS-150-H-F - Efficiency vs Output Power
Vin=9V
Vin=24V
Vin=45V
Pout(W)
10 30 50 70 90 110 130 150
50,00%
55,00%
60,00%
65,00%
70,00%
75,00%
80,00%
85,00%
90,00%
MGDS-150-H-I - Efficiency vs Output Power
Vin=9V
Vin=24V
Vin=45V
Pout(W)
10 30 50 70 90 110 130 150
50,00%
55,00%
60,00%
65,00%
70,00%
75,00%
80,00%
85,00%
90,00%
MGDS150-H-J - Efficiency vs Output Power
Vin=9V
Vin=24V
Vin=45V
Pout(W)
For locations, phone, fax, E-Mail see back cover
6
Hi-Rel
Grade
MGDM-150 Low Input Series
Gaia Converter FC02-009.12/13 Revision S
©
4
4- Electrical Characteristics (continued)
10 20 30 40 50 60 70 80 90 100
50,00%
55,00%
60,00%
65,00%
70,00%
75,00%
80,00%
85,00%
MGDS150-O-B - Efficiency vs Output Power
Vin=16V
Vin=28V
Vin=80V
Pout(W)
10 30 50 70 90 110 130 150
50,00%
55,00%
60,00%
65,00%
70,00%
75,00%
80,00%
85,00%
90,00%
MGDS-150-O-C - Efficiency vs Output Power
Vin=16V
Vin=28V
Vin=80V
Pout(W)
10 30 50 70 90 110 130 150
50,00%
55,00%
60,00%
65,00%
70,00%
75,00%
80,00%
85,00%
90,00%
MGDS-150-O-E - Efficiency vs Output Power
Vin=16V
Vin=28V
Vin=80V
Pout(W)
10 30 50 70 90 110 130 150
50,00%
55,00%
60,00%
65,00%
70,00%
75,00%
80,00%
85,00%
90,00%
MGDS-150-O-F - Efficiency vs Output Power
Vin=16V
Vin=28V
Vin=80V
Pout(W)
10 30 50 70 90 110 130 150
50,00%
55,00%
60,00%
65,00%
70,00%
75,00%
80,00%
85,00%
90,00%
MGDS-150-O-I - Efficiency vs Output Power
Vin=16V
Vin=28V
Vin=80V
Pout(W)
10 30 50 70 90 110 130 150
50,00%
55,00%
60,00%
65,00%
70,00%
75,00%
80,00%
85,00%
90,00%
95,00%
MGDS-150-O-J - Efficiency vs Output Power
Vin=16V
Vin=28V
Vin=80V
Pout(W)
For locations, phone, fax, E-Mail see back cover
7
Hi-Rel
Grade
MGDM-150 Low Input Series
Gaia Converter FC02-009.12/13 Revision S
©
4
5- Switching Frequency
7- Protection Functions
Characteristics Protection Device Recovery Limit or typical Specifications
Input undervoltage lock-out (UVLO) Turn-on, turn-off circuit
with hysteresis cycle
Automatic
recovery
Turn-on nominal
Turn-off nominal See section 4
Input overvoltage lock-out (OVLO) Turn-on, turn-off circuit
with hysteresis cycle
Automatic
recovery
Turn-on nominal
Turn-off nominal See section 4
Output current limitation protection
(OCP)
Foldback current
limitation
Automatic
recovery Maximum 110% of
output current
Output overvoltage protection (OVP) Overvoltage protection
device with latch-up Resetable Typical
115% to 135%
of output
voltage
Over temperature protection (OTP) Thermal device with
hysteresis cycle
Automatic
recovery Maximum 115°C
8- Reliability Data
Parameter Conditions Limit or typical Specifications
Switching frequency
Full temperature range
Ui min. to max.
No load to full load
Nominal, fixed 420 KHz
6- Isolation
Characteristics Conditions Temperature Specifications
Mean Time Between Failure (MTBF)
According to MIL-HDBK-217F
Ground fixed (Gf) Case at 40°C
Case at 85°C
400 000 Hrs
130 000 Hrs
Airborne, Inhabited,
Cargo (AIC)
Case at 40°C
Case at 85°C
225 000 Hrs
82 000 Hrs
Mean Time Between Failure (MTBF)
According to IEC-62380-TR
Civilian avionics,
calculators
Ambient at 55°C
100% time on 360 000 Hrs
Parameter Conditions Limit or typical Specifications
Electric strength test voltage
Input to output
Input to case
Output to case
Minimum
Minimum
Minimum
1 500 VDC / 1 min
1 500 VDC / 1 min
1 500 VDC / 1 min
Isolation resistance 500 VDC Minimum 100 MOhm
For locations, phone, fax, E-Mail see back cover
8
Hi-Rel
Grade
MGDM-150 Low Input Series
Gaia Converter FC02-009.12/13 Revision S
©
4
9- Electromagnetic Interference
Electromagnetic Interference requirements according to MIL-STD-461C/D/E standards can be easily achieved as indicated in
the following section. The following table resumes the different sections covered by these standards.
9-1 Module Compliance with MIL-STD-461C/D/E Standards
To meet the latest US military standards MIL-STD-461D/E (and also the MIL-STD-461C) requirements and in particular the
conducted noise emission CE102 (and also CE03) requirements, Gaïa Converter can propose a stand-alone ready-to-use EMI
filter module. This EMI filter module has to be used together with 4 external decoupling capacitance Cc (10nF/rated
voltage depending on isolation requirement) connected between input and case and output and case.
EMI filter module reference : FGDS-10A-50V or FGDS-20A-50V.
Please consult EMI filter datasheet for further details.
Standard Requirements MIL-STD-461C
Standard
MIL-STD-461D/E
Standard
Compliance with GAIA Converter
Module & common mode capacitance
Conducted emission (CE) :
Low frequency
High frequency
CE 01
CE 03
CE 101
CE 102
compliant module stand-alone
compliant with additionnal filter
Conducted susceptibility (CS) :
Low frequency
High frequency
CS 01
CS 02
CS 101
CS114
compliant with additionnal filter
compliant with additionnal filter
Radiated emission (RE) :
Magnetic field
Electrical field
RE 01
RE 02
RE 101
RE 102
compliant module stand-alone
compliant module stand-alone
Radiated susceptibility (RS) :
Magnetic field
Electrical field
RS 01
RS 03
RS 101
RS 103
compliant module stand-alone
compliant module stand-alone
Cc
Cc
Cc
Cc
BP
BP
MGDM-series
GI
VI Vo
Go
BP
BP
BP: Base Plate
EMI input Filter
Go
Vo
GI
VI
For locations, phone, fax, E-Mail see back cover
9
Hi-Rel
Grade
MGDM-150 Low Input Series
Gaia Converter FC02-009.12/13 Revision S
©
4
10- Thermal Characteristics
Characteristics Conditions Limit or typical Performances
Operating ambient temperature range
at full load Ambient temperature * Minimum
Maximum
- 40°C
see below
Baseplate temperature Base plate temperature Minimum
Maximum
- 40°C
+ 105°C
Storage temperature range Non functionning Minimum
Maximum
- 55°C
+ 125°C
Thermal resistance Baseplate to ambient
Rth(b-a) free air Typical 8°C/W
Note * : The upper temperature range depends on configuration, the user must ensure a max. baseplate temperature of + 105°C.
The following discussion will help designer to determine
the thermal characteristics and the operating temperature.
The MGDM-150 low input series maximum baseplate
temperature at full load must not exceed 105°C. Heat can
be removed from the baseplate via three basic
mechanisms :
• Radiation transfert : radiation is counting for less
than 5% of total heat transfert in majority of case, for
this reason the presence of radient cooling is used as
a safety margin and is not considered.
• Conduction transfert : in most of the applications,
heat will be conducted from the baseplate into an
attached heatsink or heat conducting member; heat is
conducted thru the interface.
• Convection transfert : convecting heat transfer
into air refers to still air or forced air cooling.
In majority of the applications, heat will be removed from
the baseplate either with :
• heatsink,
• forced air cooling,
• both heatsink and forced air cooling.
To calculate a maximum admissible ambient temperature
the following method can be used.
Knowing the maximum baseplate temperature
Tbase = 105°C of the module, the power used Pout and
the efficiency η :
• determine the power dissipated by the module Pdiss
that should be evacuated :
Pdiss = Pout(1/ηη
ηη
η - 1) (A)
• determine the maximum ambient temperature :
Ta = 105°C - Rth(b-a) x Pdiss (B)
where Rth(b-a) is the thermal resistance from the
baseplate to ambient.
This thermal Rth(b-a) resistance is the summ of :
• the thermal resistance of baseplate to heatsink
(Rth(b-h)). The interface between baseplate and
heatsink can be nothing or a conducting member, a
thermal compound, a thermal pad.... The value of
Rth(b-h) can range from 0.4°C/W for no interface down
to 0.1°C/W for a thermal conductive member inter-
face.
• the thermal resistance of heatsink to ambient air
(Rth(h-a)), which is depending of air flow and given
by heatsink supplier.
Fischer Elektronic and Thermalloy are heasink manufacturers. «Silpad» © is a registered trademark of Bergquist.
Note* : Silpad performance are for Silpad 400 with pressure conditions of 50 Psi. Surface of MGDS-150 series is 5,5 inch2.
The table hereafter gives some example of thermal resistance for different heat transfert configurations.
For locations, phone, fax, E-Mail see back cover
10
Hi-Rel
Grade
MGDM-150 Low Input Series
Gaia Converter FC02-009.12/13 Revision S
©
4
The module case is built with a copper IMS (isolated metalic
substrate ) crimped on an aluminum frame that provides
case rigidity. The IMS surface is the module base plate
that need to be reported to heat sink to achieve proper
cooling. If for some reasons like poor module report, the
IMS base plate is subject to mechanical overstress, module's
electrical characteristics may be definitely affected.
A typical example of damageable report is the use of
thick thermal interface with usual screwing torque applied
on mounting screws. This combination causes a high pres-
sure on baseplate center due to thermal interface material
compression. The final consequence is a slight IMS bending
that can conduct for the module to fail high voltage isola-
tion leading to heavy electrical damage on internal cir-
cuit.
screw
PCB
Thermal Pad
Heatsink
screw
PCB
Too ThickThermal Pad
Heatsink
Base plate overstress
9- Thermal Characteristics (continued) : Heatsink Mounting
1
2
3
4
- do not exceed recommended screwing torque of
0,7 N.m (6 lbs.in)
- prefer thin thermal pad with thickness lower
than 0,34 mm (0.015").
GAIA Converter recommends to use thin thermal
pads instead of thermal compound like grease.
- take care to reflow module leads only when all
assembly operations are completed.
- do not report module on surfaces with poor
flatness characteristics. GAIA Converter recommends
not to overflow 0,1mm/m for the surface flatness.
Poor report not recommended
Example of banned thermal interface : Bergquist Gap Pad VO Ultra Soft
1. Choice of the thermal gap pad : its shape must be the same
as the module. The dimensions of the gap pad can be a little
larger than the module.
2. Screw the converter to the heatsink and/or to the board.
The four screws have to be screwed in a "X" sequence.
• Lightly finger-tighten all screws and run several «X» sequences
before achieving final torque to get homogeneous tightening.
• Torque screws from 0,35 N.m (3 lbs.in) to 0,7 N.m (6 lbs.in).
3. Screw the heatsink to the board.
4. Solder the pins of the converters on the board.
This sequence avoids mechanical stresses on the converters
that could lead to stress internal components or assemblies
and cause their failures.
To mount properly the module to heatsink, some important recommendations need to be taken into account in order to avoid
overstressing conditions that might lead to premature failures.
The good practice is to respect the 4 following recommendations:
Example of recommended thermal interface : Bergquist Silpad 400
Gaia converter suggests to follow the procedure hereunder for the mechanical assembly procedure in order to avoid any stress on the
pins of the converters. It is good practice to be sure to mount the converters first mechanically, then solder the units in place.
For locations, phone, fax, E-Mail see back cover
11
Hi-Rel
Grade
MGDM-150 Low Input Series
Gaia Converter FC02-009.12/13 Revision S
©
4
11- Environmental Qualifications
The modules have been subjected to the following environmental qualifications.
Characteristics Conditions Severity Test procedure
Climatic Qualifications
Life at high
temperature
Duration
Temperature / status of unit
Test D : 1 000 Hrs
@ 105°C case, unit operating
@ 125°C ambient, unit not operating
MIL-STD-202G
Method 108A
Altitude
Altitude level C
Duration
Climb up
Stabilization
Status of unit
40 000 ft@-55°C
30 min.
1 000 ft/min to 70 000 ft@-55°C,
30 min.
unit operating
MIL-STD-810E
Method 500.3
Humidity cyclic
Number of cycle
Cycle duration
Relative humidity variation
Temperature variation
Status of unit
10
Cycle I : 24 Hrs
60 % to 88 %
31°C to 41°C
unit not operating
MIL-STD-810E
Method 507.3
Humidity steady
Damp heat
Temperature
Duration
Status of unit
93 % relative humidity
40°C
56 days
unit not operating
MIL-STD-202G
Method 103B
Salt atmosphere
Temperature
Concentration NaCl
Duration
Status of unit
35°C
5 %
48 Hrs
unit not operating
MIL-STD-810E
Method 509.3
Temperature
cycling
Number of cycles
Temperature change
Transfert time
Steady state time
Status of unit
200
-40°C / +85°C
40 min.
20 min.
unit operating
MIL-STD-202A
Method 102A
Temperature
shock
Number of shocks
Temperature change
Transfert time
Steady state time
Status of unit
100
-55°C / +105°C
10 sec.
20 min.
unit not operating
MIL-STD-202G
Method 107G
Mechanical Qualifications
Vibration
(Sinusoidal)
Number of cycles
Frequency / amplitude
Frequency / acceleration
Duration
Status of unit
10 cycles in each axis
10 to 60 Hz / 0.7 mm
60 to 2 000 Hz / 10 g
2h 30 min. per axis
unit not operating
MIL-STD-810D
Method 514.3
Shock
(Half sinus)
Number of shocks
Peak acceleration
Duration
Shock form
Status of unit
3 shocks in each axis
100 g
6 ms
1/2 sinusoidal
unit not operating
MIL-STD-810D
Method 516.3
Bump
(Half sinus)
Number of bumps
Peak acceleration
Duration
Status of unit
2 000 Bumps in each axis
40 g
6 ms
unit not operating
MIL-STD-810D
Method 516.3
For locations, phone, fax, E-Mail see back cover
12
Hi-Rel
Grade
MGDM-150 Low Input Series
Gaia Converter FC02-009.12/13 Revision S
©
4
12- Description of Protections
12-2 Output Over Current Protection (OCP)
The MGDM-150 low input series incorporates a foldback current
limit and protection circuit. When the output current reaches
110% of it’s full-rated current (Icurrent limit), the output vol-
tage falls and output current falls along the foldback line as
described in the figure herein. The module restart automatically
to normal operation when overcurrent is removed.
12-3 Output Overvoltage Protection (OVP)
Each circuit has an internal overvoltage protection circuit that
monitors the voltage accross the output power terminals.
It is designed to latch the converter off at 115% to 135% of
output voltage.
Once in OVP protection, the module will restart with the On/
Off function or with the input bus restart.
The MGDM-150 low input series include 5 types of protection
devices that are powered and controlled by a fully independant
side power stage.
12-4 Over Temperature Protection (OTP)
A thermal protection device adjusted at 115°C (+/-5%) internal
temperature with 10°C hysteresis cycle will inhibit the mo-
dule as long as the overheat is present and restores to nor-
mal operation automatically when overheat is removed. The
efficiency of the OTP function is warranty with the module
mounted on a heatsink.
Iout
Vout
Icurrent limit
110% of full
rated current
Baseplate
Temperature
On
115˚c
Off
10˚c
12-1 Input Undervoltage Lockout (UVLO) and
Overvoltage Lockout (OVLO)
12-1-1 Undervoltage Lockout (UVLO)
An undervoltage protection is implemented to lock off the
converter as long as the input voltage has not reached the
UVLO turn-on threshold (see section 4 for value) which is the
minimum input voltage required to operate without damaging
the converter.
12-1-2 Overvoltage Lockout (OVLO)
An overvoltage protection will inhibit the module when input
voltage reaches the overvoltage lockout turn-off threshold (see
section 4 for value) and restores to normal operation
automatically when the input voltage drops below the
overvoltage Lockout turn on threshold.
Vin
On
OVLO
Turn-off
Off
UVLO 
Turn-on
UVLO 
Turn-off
OVLO
Turn-on
For locations, phone, fax, E-Mail see back cover
13
Hi-Rel
Grade
MGDM-150 Low Input Series
Gaia Converter FC02-009.12/13 Revision S
©
4
13- Description of Functions
13-1 Trim Function
The output voltage Vo may be trimmed in a range of
10%/110% of the nominal output voltage via a single external
trimpot or fixed resistor.
Trim Up Function
Do not attempt to trim the module higher than 110% of
nominal output voltage as the overvoltage protection may
occur.
Also do not exceed the maximum rated output power when
the module is trimmed up.
The trim up resistor must be connected to S+ pin.
The trim up resistance must be calculated with the following
formula :
Ru = R1 x (V0-Vref) x V0nom - R1 - R2
(V0-V0nom) x Vref
Note : This formula is a reduced form of the real expres-
sion that gives an approached value. To get an accurate
value, please use the trim calculator in our web site at
www.gaia-converter.com/calculator.trimcalculation.php
Trim Down Function
Do not trim down more than -90% of nominal output vol-
tage or 1 Vdc.
The available output power is reduced by the same
percentage that output voltage is trimmed down.
The trim down resistor must be connected to S- pin.
The trim down resistance must be calculated with the
following formula :
Rd = (R2 + R1) x V0 - (R2 x V0nom)
V0nom - V0
Note : This formula is a reduced form of the real expres-
sion that gives an approached value. To get an accurate
value, please use the trim calculator in our web site at
www.gaia-converter.com/calculator.trimcalculation.php
Trim via a voltage
The output voltage is given by the following formula :
V0 = (1 + R1 x (Vcont - 1) ) x V0nom
(R1 + R2) Vref
Parameter Unit Min. Typ. Max.
Trim reference Vdc 2,45 2,5 2,55
Resistor R1 Ohm / 3800 /
Resistor R2 Ohm / 270 /
Trim capacitor µF / 1 /
BP
MGDM150
S-
Gin
Vin Vo
On/Off
Go
Trim
S+
Sync
Share
5
3
2
4
1
6
7
8
10
9
Load
Rd
R1 R2
1µF
Vref=
2.5V
Error amp.
MGDM150
S-
Gin
Vin Vo
On/Off
Go
Trim
S+
Sync
Share
5
3
2
4
1
6
7
8
10
9
Load
Ru
R1 R2
1µF
Vref=
2.5V
Error amp.
Vcontrol
100nF
BAT54
BP
MGDM150
S-
Gin
Vin Vo
On/Off
Go
Trim
S+
Sync
Share
5
3
2
4
1
6
7
8
10
9
Load
Ru
R1 R2
1µF
Vref=
2.5V
Error amp.
For locations, phone, fax, E-Mail see back cover
14
Hi-Rel
Grade
MGDM-150 Low Input Series
Gaia Converter FC02-009.12/13 Revision S
©
4
BP
MGDM150
S-
Gin
Vin Vo
On/Off
Go
Trim
S+
Sync
Share
5
3
2
4
1
6
7
8
10
9
Load
13- Description of Functions (continued)
13-3 On/Off Function
The control pin 4 (On/Off) can be used for applications requiring
On/Off operation. This may be done with an open collector
transistor, a switch, a relay or an optocoupler. Several
converters may be disabled with a single switch by connecting
all
On/Off pins together.
• The converter is disabled by pulling low the pin 4.
• No connection or high impedance on pin 4 enables the
converter.
By releasing the On/Off function, the converter will restart
within the start up time specifications given in table section
4. For further details please consult ‘’Logic On/Off’’ application note.
13-4 Synchronization Function
An external clock with rectangular «Pull Up» signals can be
used to lock one or more converters. The external clock si-
gnal should have a frequency range from 860KHz to 940KHz,
a low level below 0,5V a high level of 4V (+/-0.5V), a rise
time of 30 ns max. and a drop time of 100ns max.
Parameter Unit Min. Typ. Max. Notes, conditions
On/Off module enable voltage Vdc 3.5 / 4 Open, the switch must not sink more than 100µA
On/Off module disable voltage Vdc 0 / 0.5 The switch must be able to sink 1mA
On/Off alarm level Vdc 0 / 0.5 UVLO, OVLO, OVP, OTP, faulty module
On/Off module enable delay ms / / 30 The module restarts with the same delay after alarm mode removed
On/Off module disable delay µs / / 100 Vi nominal, full load
Vin
4V
+/- 0,5
T/2
Vsync
0V
100ns
max
30ns
max
T
( 860Khz < F < 940Khz )
13-2 Sense Function
If the load is separated from the output by any line lenght,
some of these performance characteristics will be degraded
at the load terminals by an amount proportional to the
impedance of the load leads. Sense connections enable to
compensate the line drop at a maximum of +/-10% of output
voltage. The overvoltage protection will be activated and module
will shut down if remote sense tries to boost output voltage
above 110% of nominal output voltage. Connection is described
in figure herein.
BP
MGDM150
S-
Gin
Vin Vo
On/Off
Go
Trim
S+
Sync
Share
5
3
2
4
1
6
7
8
10
9
Load
On/Off
Gi
Vi
BP
MGDM150
S-
Gin
Vin Vo
On/Off
Go
Trim
S+
Sync
Share
5
3
2
4
1
6
7
8
10
9
Load
Totem pole
output
Gi
Vi
100pF
1N4148 4.7k
Ext. clock
For locations, phone, fax, E-Mail see back cover
15
Hi-Rel
Grade
MGDM-150 Low Input Series
Gaia Converter FC02-009.12/13 Revision S
©
4
14- Application Notes
14-1 Synchronization of Modules
The MGDM-150 low input series provides a synchronization
function trough the pin 2 (Synchro) to enable automatic
synchronisation between several converters.
If several converters are used, they lock themselves into
the highest switching frequency.
The synchronization signal available on pin 2 is referenced
to ground in (Gi) and the signal shape is the double of the
switching frequency (i.e 2x420KHz). It is a rectangular
signal with 3.5 Vp (+/-0.5V) amplitude with an impedance
of 4,7 KOhm on low level.
14-2 Connection of Modules in Series
The output of single output units can be connected in
series without any precautions to provide higher output
voltage level.
Nevertheless, GAIA Converter recommends to protect each
individual output by a low power shottky diode rated with
the maximum current of the converter to avoid reverse
polarity at any output.
Reverse polarity may occur at start up if the output volta-
ges do not rise at the same time.
14-3 Connection of Modules in Parallel
The MGDM-150 low input series features a «parallel
operation function» to increase the output power capability
of a single unit by connecting the outputs of 2 or more
converters in parallel. By connecting the «Share» pin of
each module together, the units will share the load current
equally within a few percent. Up to 5 converters can be
parallelized.
The «Share» signal is a DC voltage which varies between
0Vdc and 5Vdc referenced to «Sense -» and depending on
the output load.
10nF
10nF
10nF
10nF
BP
BP
MGDM150
S-
Gin
Vin Vo
On/Off
Go
Trim
S+
Sync
Share
5
3
2
4
1
6
7
8
10
9
(*)
BP: Base Plate
10nF
10nF
10nF
10nF
100µF
BP
BP
MGDM150
S-
Gin
Vin Vo
On/Off
Go
Trim
S+
Sync
Share
5
3
2
4
1
6
7
8
10
9
(*)
100µF
10nF
10nF
10nF
10nF
BP
BP
MGDM150
S-
Gin
Vin Vo
On/Off
Go
Trim
S+
Sync
Share
5
3
2
4
1
6
7
8
10
9
(*)
BP: Base Plate
10nF
10nF
10nF
10nF
100µF
BP
BP
MGDM150
S-
Gin
Vin Vo
On/Off
Go
Trim
S+
Sync
Share
5
3
2
4
1
6
7
8
10
9
(*)
100µF
10nF
10nF
10nF
10nF
BP
BP
(*)
BP: Base Plate
10nF
10nF
10nF
10nF
BP
BP
(*)
On/Off
MGDM150
S-
Gin
Vin Vo
On/Off
Go
Trim
S+
Sync
Share
5
3
2
4
1
6
7
8
10
9
MGDM150
S-
Gin
Vin Vo
On/Off
Go
Trim
S+
Sync
Share
5
3
2
4
1
6
7
8
10
9
For locations, phone, fax, E-Mail see back cover
16
Hi-Rel
Grade
MGDM-150 Low Input Series
Gaia Converter FC02-009.12/13 Revision S
©
4
Bottom view
15- Dimensions
Dimensions are given in mm (inches). Tolerance : +/- 0,2 mm (+/- 0.01 “) unless otherwise indicated.
Weight : 110 grams (3,9 Ozs) max.
18- Connections
910 678
2 4 5
31
10,16
(0.4)
7,62
(0.3)
7,62
(0.3)
10,16
(0.4)
57,912
(2.28)
48,26
(1.90)
50,8
(2.00)
60,95
(2.40)
Mouting Hole
0 3,1 (0,122) 9,894
(0.39)
7,62
(0.3) 5,08 (0.2)
4,826
(0.19)
9,589
(0.38)
R2.4 (0,1)
CH 2x2
Use this side 
for heat sinking
5,6 min
(0.22)
6,8 max
(0.267)
12,7 Max
(0.5)
0,5 (0.019)
Pin dimensions : 
Pins : 1, 2, 3, 4, 5, 7, 8, 9 : Ø 1 mm (0.04”)
Pins : 6, 10 : Ø 2 mm (0.08”)
Pin Single Output
1 - Input (Gi)
2 Synchro (Sync)
3 Share
4 On/Off
5 + Input (Vi)
6 + Output (Vo)
7 Sense + (S+)
8 Trim (Trim)
9 Sense - (S-)
10 - Output (Go)
16- Materials
Frame : Aluminium alodined coating.
Baseplate : Copper with tin finishing.
Pins : Plated with pure matte tin over nickel underplate.
17- Product Marking
Side face : Company logo, location of manufacturing.
: Module reference : MGDx-150-»X»-»Y».
Date code : year and week of manufacturing, suffix, /option.
Information given in this datasheet is believed to be accurate and reliable. However, no responsibility is assumed for the consequence of its use nor for any infringement of patents or other rights of third parties which may result from its use.
These products are sold only according to GAIA Converter general conditions of sale, unless otherwise confirmed by writing. Specifications subject to change without notice.
Printed in France by Gaia Converter FC02-009.12/13 Revision S Graphisme : Philippe Clicq
Represented by :
For more detailed specifications and applications information, contact :
International Headquarters
GAÏA Converter - France
ZI de la Morandière
33185 LE HAILLAN - FRANCE
Tel. : + (33)-5-57-92-12-80
Fax : + (33)-5-57-92-12-89
North American Headquarters
GAÏA Converter Canada, Inc
4038 Le Corbusier Blvd
LAVAL, QUEBEC - CANADA H7L 5R2
Tel. : (514)-333-3169
Fax : (514)-333-4519