MQFL-28V-28S

MQFL-28V-28S
Single Output
H igH R eliability DC-DC C onveRteR
16-40V
5.5-50V
28V
3.3A
90% @ 1.65A / 89% @ 3.3A
Continuous Input
Transient Input
Output
Output
Efficiency
F ull P oweR o PeRation : -55ºC
to
+125ºC
The MilQor® series of high-reliability DC-DC converters
brings SynQor’s field proven high-efficiency synchronous
rectifier technology to the Military/Aerospace industry.
SynQor’s innovative QorSeal® packaging approach ensures
survivability in the most hostile environments. Compatible
2
ENA
with the industry standard format, these converters operate
RE
SHA
at a fixed frequency, have no opto-isolators, and follow
conservative component derating guidelines.
-ES
S-Y
-28
-28V tEr
+VIN
They are
N
IN RT
ILITY
STAB
designed and manufactured to comply with a wide range of
1
ENA
VEr
FL
MQ DC Con [email protected]
E
AG
DC8Vo
1C
in 2
5-30
320
28V
D/C
T
C OU
SYN
C IN
SYN
military standards.
+SNS
-SNS
RTN
OUT
T
+VOU
X10
1W
0
000
000
S/n
Meets all -704 and -1275D under-voltage transients
Design Process
MQFL series converters are:
• Designed for reliability per NAVSO-P3641-A guidelines
• Designed with components derated per:
— MIL-HDBK-1547A
— NAVSO P-3641A
Qualification Process
MQFL series converters are qualified to:
• MIL-STD-810F
— consistent with RTCA/D0-160E
• SynQor’s First Article Qualification
— consistent with MIL-STD-883F
• SynQor’s Long-Term Storage Survivability Qualification
• SynQor’s on-going life test
In-Line Manufacturing Process
• AS9100 and ISO 9001 certified facility
• Full component traceability
• Temperature cycling
• Constant acceleration
• 24, 96, 160 hour burn-in
• Three level temperature screening
Product# MQFL-28V-28S
Phone 1-888-567-9596
DesigneD & ManufactureD in the usa
featuring Qorseal® hi-rel asseMbly
Features
•
•
•
•
•
•
•
•
Fixed switching frequency
No opto-isolators
Parallel operation with current share
Remote sense
Clock synchronization
Primary and secondary referenced enable
Continuous short circuit and overload protection
Input under-voltage and over-voltage shutdown
Specification Compliance
MQFL series converters (with MQME filter) are designed to meet:
• MIL-HDBK-704-8 (A through F)
• RTCA/DO-160 Section 16, 17, 18
• MIL-STD-1275 (B, D)
• DEF-STAN 61-5 (part 6)/(5, 6)
• MIL-STD-461 (C, D, E, F)
• RTCA/DO-160(E, F, G) Section 22
www.SynQor.com
Doc.# 005-0005081 Rev. G
05/27/15
Page 1
MQFL-28V-28S
Output: 28V
Current: 3.3A
Technical Specification
BLOCK DIAGRAM
1
INPUT
RETURN
2
REGULATION STAGE
BOOST
CONVERTER
SWITCHES AND
CONTROL
CURRENT
SENSE
CASE
STABILITY
GATE DRIVERS
3
CURRENT
LIMIT
UVLO
ENABLE 1
4
SYNC OUT
5
SYNC IN
6
ISOLATION STAGE
ISOLATION BARRIER
+Vin
+Vout
8
OUTPUT
RETURN
GATE DRIVERS
MAGNETIC
PRIMARY
CONTROL
7
SECONDARY
CONTROL
DATA COUPLING
12
ENABLE 2
11
SHARE
10
+ SENSE
9
− SENSE
BIAS POWER
CONTROL
POWER
TRANSFORMER
TYPICAL CONNECTION DIAGRAM
External bulk capacitor
28 Vdc
+
_
RSTABILITY
CSTABILITY
Product# MQFL-28V-28S
open
means
on
Phone 1-888-567-9596
1
+VIN
2
IN RTN
3
STABILITY
4
ENA 1
5
SYNC OUT
6
SYNC IN
ENA 2 12
SHARE 11
MQFL
www.SynQor.com
+SNS 10
-SNS 9
open
means
on
+
Load
OUT RTN 8
+VOUT 7
Doc.# 005-0005081 Rev. G
05/27/15
_
Page 2
MQFL-28V-28S
Output: 28V
Current: 3.3A
Technical Specification
Under-Voltage Transient Profile
Boost-Converter is armed (or re-armed)
when Vin exceeds this value
20
VARM (~18V)
Boost-Converter Operational Area
15
dV ≤ 0.1V
μs
dt
VIN10
12.5V
5.5V
5
0
0
1.5
9
27
Time (s)
Under-Voltage Transient Profile showing when the boost-converter is guaranteed to be operational. Before the boost
converter will operate, it must first be armed (or re-armed) by making VIN greater than VARM.
Note:
This Under-Voltage Transient Profile is designed to comply (with appropriate margins) with all initial-engagement surges,
starting or cranking voltage transients and under-voltage surges specified in:
• MIL-STD-704-8 (A through F)
• RTCA/DO-160
• MIL-STD-1275
• DEF-STAN 61-5 (part 6)/5 (operational portions)
Product# MQFL-28V-28S
Phone 1-888-567-9596
www.SynQor.com
Doc.# 005-0005081 Rev. G
05/27/15
Page 3
MQFL-28V-28S
Output: 28V
Current: 3.3A
Technical Specification
MQFL-28V-28S ELECTRICAL CHARACTERISTICS
Parameter
Min. Typ. Max. Units Notes & Conditions
Vin=28V dc ±5%, Iout=3.3A, CL=0µF, free running (see Note 10) boostconverter non-operational unless otherwise specified
Specifications subject to change without notice
ABSOLUTE MAXIMUM RATINGS
Input Voltage
Non-Operating
Operating
Reverse Bias (Tcase = 125ºC)
Reverse Bias (Tcase = -55ºC)
Isolation Voltage (I/O to case, I to O)
Continuous
Transient (≤100µs)
Operating Case Temperature
Storage Case Temperature
Lead Temperature (20s)
Voltage at ENA1, ENA2
INPUT CHARACTERISTICS
Operating Input Voltage Range
“
Input Under-Voltage Lockout
Turn-On Voltage Threshold
Turn-Off Voltage Threshold
Lockout Voltage Hysteresis
Input Over-Voltage Shutdown
Turn-Off Voltage Threshold
Turn-On Voltage Threshold
Shutdown Voltage Hysteresis
Maximum Input Current
No Load Input Current (operating)
Disabled Input Current (ENA1)
Disabled Input Current (ENA2)
Input Terminal Current Ripple (pk-pk)
OUTPUT CHARACTERISTICS
Output Voltage Set Point (Tcase = 25ºC)
Ouptut Voltage Set Point Over Temperature
Output Voltage Line Regulation
Output Voltage Load Regulation
Total Output Voltage Range
Output Voltage Ripple and Noise Peak to Peak
Operating Output Current Range
Operating Output Power Range
Output DC Current-Limit Inception
Short Circuit Output Current
Back-Drive Current Limit while Enabled
Back-Drive Current Limit while Disabled
Maximum Output Capacitance
DYNAMIC CHARACTERISTICS
Output Voltage Deviation Load Transient
For a Pos. Step Change in Load Current
For a Neg. Step Change in Load Current
Settling Time (either case)
Output Voltage Deviation Line Transient
For a Pos. Step Change in Line Voltage
For a Neg. Step Change in Line Voltage
Settling Time (either case)
Turn-On Transient
Output Voltage Rise Time
Output Voltage Overshoot
Turn-On Delay, Rising Vin
Turn-On Delay, Rising ENA1
Turn-On Delay, Rising ENA2
EFFICIENCY
Iout = 3.3A (16Vin)
Iout = 1.65A (16Vin)
Iout = 3.3A (28Vin)
Iout = 1.65A (28Vin)
Iout = 3.3A (40Vin)
Iout = 1.65A (40Vin)
Load Fault Power Dissipation
Short Circuit Power Dissipation
Product# MQFL-28V-28S
-500
-800
-55
-65
-1.2
60
60
-0.8
-1.2
V
V
V
V
500
800
125
135
300
50
V
V
°C
°C
°C
V
16
5.5
28
28
40
50
V
V
14.75
13.80
0.50
15.50
14.40
1.10
16.00
15.00
1.80
V
V
V
54.0
50.0
2.0
56.8
51.4
5.3
60.0
54.0
8.0
7
160
5
50
120
V
V
V
A
mA
mA
mA
mA
28.28
28.40
20
150
28.56
100
3.3
92.4
5.0
5.6
50
3,000
V
V
mV
mV
V
mV
A
W
A
A
A
mA
µF
-400
400
50
1200
200
mV
mV
µs
250
800
800
500
mV
mV
µs
6
0
5.5
3.0
1.5
10
2
8.0
6.0
3.0
ms
%
ms
ms
ms
24
24
%
%
%
%
%
%
W
W
110
2
25
80
27.72
27.60
-20
120
27.44
0
0
3.4
3.7
-1200
-800
-800
28.00
28.00
0
135
28.00
30
3.8
4.1
1
10
84
88
84
86
83
85
Phone 1-888-567-9596
89
91
89
90
88
89
14
16
Group A
Subgroup
(see Note 13)
See Note 1
HB Grade Products, See Notes 2 & 15
Continuous
Transient, 1s; see Under-Voltage Transient Profile
See Note 3
1, 2, 3
1, 2, 3
1, 2, 3
See Note 3
Vin = 16V; Iout = 3.3A
See Note 5
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
Bandwidth = 100kHz – 10MHz; see Figure 14
Vout at sense leads
“
“
“ ; Vout @ (Iout=0 A) - Vout @ (Iout=3.3A)
“
Bandwidth = 10 MHz; CL=11µF
1
2, 3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
See Note 5
1, 2, 3
1, 2, 3
See Note 5
See Note 4
Vout ≤ 1.2V
See Note 6
Total Iout step = 1.65A‹-›3.3A, 0.33A‹-›1.65A; CL=11µF
“
See Note 7
Vin step = 16V‹-›50V; CL=11µF; see Note 8
4, 5, 6
4, 5, 6
See Note 7
Vout = 2.8V-›25.2V
4, 5, 6
See Note 5
4, 5, 6
4, 5, 6
4, 5, 6
ENA1, ENA2 = 5V; see Notes 9 & 12
ENA2 = 5V; see Note 12
ENA1 = 5V; see Note 12
1, 2, 3
Iout at current limit inception point; See Note 4
Vout ≤ 1.2V
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Doc.# 005-0005081 Rev. G
1
1
05/27/15
Page 4
MQFL-28V-28S
Output: 28V
Current: 3.3A
Technical Specification
MQFL-28V-28S ELECTRICAL CHARACTERISTICS (Continued)
Parameter
Min. Typ. Max. Units Notes & Conditions
Vin=28V dc ±5%, Iout=3.3A, CL=0µF, free running (see Note 10) boostconverter non-operational unless otherwise specified
Specifications subject to change without notice
ISOLATION CHARACTERISTICS
Isolation Voltage
Input RTN to Output RTN
Any Input Pin to Case
Any Output Pin to Case
Isolation Resistance (in rtn to out rtn)
Isolation Resistance (any pin to case)
Isolation Capacitance (in rtn to out rtn)
FEATURE CHARACTERISTICS
Switching Frequency (free running)
Synchronization Input
Frequency Range
Logic Level High
Logic Level Low
Duty Cycle
Synchronization Output
Pull Down Current
Duty Cycle
Enable Control (ENA1 and ENA2)
Off-State Voltage
Module Off Pulldown Current
On-State Voltage
Module On Pin Leakage Current
Pull-Up Voltage
BOOST-CONVERTER OPERATION
Input Voltage Arming Value
Switching Frequency
Input Terminal Current Ripple (RMS)
Total Converter Efficiency
Iout = 1.65A (10Vin)
Iout = 1.65A (16Vin)
Iout = 3.3A (16Vin)
RELIABILITY CHARACTERISTICS
Calculated MTBF (MIL-STD-217F2)
GB @ Tcase = 70ºC
AIF @ Tcase = 70ºC
WEIGHT CHARACTERISTICS
Device Weight
Group A
Subgroup
(see Note 13)
Dielectric strength
500
500
500
100
100
V
V
V
MΩ
MΩ
nF
1
1
1
1
1
1
600
kHz
1, 2, 3
500
2.0
-0.5
20
600
10
0.8
80
kHz
V
V
%
1, 2, 3
1, 2, 3
1, 2, 3
See Note 5
20
25
75
mA
%
44
500
550
0.8
80
2
3.2
4.0
17.5
600
18.0
670
1
20
4.5
18.8
740
V
µA
V
µA
V
V
kHz
A
86
88
87
%
%
%
2200
390
103 Hrs.
103 Hrs.
79
g
VSYNC OUT = 0.8V
Output connected to SYNC IN of other MQFL unit
Current drain required to ensure module is off
Imax draw from pin allowed with module still on
See Figure A
See Note 5
See Note 5
1, 2, 3
See Note 5
1, 2, 3
See Note 5
1, 2, 3
1, 2, 3
1
Vin = 16V; Iout = 3.3A
1
1
Electrical Characteristics Notes
1. Converter will undergo input over-voltage shutdown.
2. Derate output power to 50% of rated power at Tcase = 135ºC (see Figure 5). 135ºC is above specified operating range.
3. High or low state of input voltage must persist for about 200µs to be acted on by the lockout or shutdown circuitry.
4. Current limit inception is defined as the point where the output voltage has dropped to 90% of its nominal value.
5. Parameter not tested but guaranteed to the limit specified.
6. Load current transition time ≥ 10µs.
7. Settling time measured from start of transient to the point where the output voltage has returned to ±1% of its final value.
8. Line voltage transition time ≥ 100µs.
9. Input voltage rise time ≤ 250µs.
10. Operating the converter at a synchronization frequency above the free running frequency will cause the converter’s efficiency to be slightly reduced and it
may also cause a slight reduction in the maximum output current/power available. For more information consult the factory.
11. SHARE pin outputs a power failure warning pulse during a fault condition. See Current Share section of the Control Features description.
12. After a disable or fault event, module is inhibited from restarting for 300ms. See Shut Down section of the Control Features description.
13. Only the ES and HB grade products are tested at three temperatures. The C- grade products are tested at one temperature. Please refer to the
Construction and Environmental Stress Screening Options table for details.
14. These derating curves apply for the ES and HB grade products. The C- grade product has a maximum case temperature of 70ºC and a maximum junction
temperature rise of 20ºC above Tcase.
15. The specified operating case temperature for ES grade products is -45ºC to 100ºC. The specified operating case temperature for C- grade
products is 0ºC to 70ºC.
Product# MQFL-28V-28S
Phone 1-888-567-9596
www.SynQor.com
Doc.# 005-0005081 Rev. G
05/27/15
Page 5
MQFL-28V-28S
Output: 28V
Current: 3.3A
100
100
95
95
90
90
85
85
Efficiency (%)
Efficiency (%)
Technical Figures
80
75
70
80
75
70
16 Vin
28 Vin
65
0.6
0.9
1.2
1.5
1.8
2.1
2.4
2.7
3.0
40 Vin
60
-55ºC
60
0.3
28 Vin
65
40 Vin
0.0
16 Vin
3.3
25ºC
Load Current (A)
Figure 2: Efficiency at nominal output voltage and 60% rated power vs.
case temperature for input voltage of 16V, 28V, and 40V.
20
20
18
18
16
16
Power Dissipation (W)
Power Dissipation (W)
Figure 1: Efficiency at nominal output voltage vs. load current for
minimum, nominal, and maximum input voltage at Tcase=25°C.
14
12
10
8
6
16 Vin
4
14
12
10
8
6
2
0.6
0.9
1.2
1.5
1.8
2.1
2.4
2.7
28 Vin
40 Vin
2
3.0
0
-55ºC
0
0.3
16 Vin
4
28 Vin
0.0
3.3
40 Vin
25ºC
Load Current (A)
35
3.5
98
30
3.0
84
2.5
70
2.0
56
1.5
42
Tjmax = 105º C
Tjmax = 125º C
0.0
Tjmax = 145º C
25
45
65
85
105
125
145
Output Voltage (V)
112
Pout (W)
Iout (A)
Figure 4: Power dissipation at nominal output voltage and 60% rated
power vs. case temperature for input voltage of 16V, 28V, and 40V.
4.0
0.5
25
20
15
28
10
14
5
0
0
0.0
Case Temperature (ºC)
Figure 5: Output Current / Output Power derating curve as a function of
Tcase and the Maximum desired power MOSFET junction temperature at
Vin = 28V (see Note 14).
Product# MQFL-28V-28S
125ºC
Case Temperature (ºC)
Figure 3: Power dissipation at nominal output voltage vs. load current
for minimum, nominal, and maximum input voltage at Tcase=25°C.
1.0
125ºC
Case Temperature (ºC)
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0.5
1.0
1.5
2.0
2.5
Load Current (A)
3.0
3.5
4.0
4.5
Figure 6: Output voltage vs. load current showing typical current limit
curves at Vin = 28V.
www.SynQor.com
Doc.# 005-0005081 Rev. G
05/27/15
Page 6
MQFL-28V-28S
Output: 28V
Current: 3.3A
Technical Figures
Figure 7: Turn-on transient at full resistive load and zero output
capacitance initiated by ENA1. Input voltage pre-applied. Ch 1: Vout
(5V/div). Ch 2: ENA1 (5V/div).
Figure 8: Turn-on transient at full resistive load and 3mF output
capacitance initiated by ENA1. Input voltage pre-applied. Ch 1: Vout
(5V/div). Ch 2: ENA1 (5V/div).
Figure 9: Turn-on transient at full resistive load and zero output
capacitance initiated by ENA2. Input voltage pre-applied. Ch 1: Vout
(5V/div). Ch 2: ENA2 (5V/div).
Figure 10: Turn-on transient at full resistive load and zero output
capacitance initiated by Vin. ENA1 and ENA2 both previously high. Ch
1: Vout (5V/div). Ch 2: Vin (10V/div).
Figure 11: Output voltage response to step-change in load current 50%100%-50% of Iout (max). Load cap: 1µF ceramic cap and 10µF, 100mΩ
ESR tantalum cap. Ch 1: Vout (500mV/div). Ch 2: Iout (2A/div).
Figure 12: Output voltage response to step-change in load current 0%50%-0% of Iout (max). Load cap: 1µF ceramic cap and 10µF, 100mΩ
ESR tantalum cap. Ch 1: Vout (500mV/div). Ch 2: Iout (2A/div).
Product# MQFL-28V-28S
Phone 1-888-567-9596
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Doc.# 005-0005081 Rev. G
05/27/15
Page 7
MQFL-28V-28S
Output: 28V
Current: 3.3A
Technical Figures
Figure 13: Output voltage response to step-change in input voltage (16V 50V - 16V). Load cap: 10µF, 100mΩ ESR tantalum cap and 1µF ceramic
cap. Ch 1: Vout (500mV/div). Ch 2: Vin (20V/div).
Figure 14: Test set-up diagram showing measurement points for Input
Terminal Ripple Current (Figure 15) and Output Voltage Ripple (Figure
16).
Figure 15: Input terminal current ripple, ic, at full rated output current
and nominal input voltage with SynQor MQ filter module (50mA/div).
Bandwidth: 20MHz. See Figure 14.
Figure 16: Output voltage ripple, Vout, at nominal input voltage and
rated load current (20mV/div). Load capacitance: 1μF ceramic capacitor
and 10μF tantalum capacitor. Bandwidth: 10MHz. See Figure 14.
Figure 17: Rise of output voltage after the removal of a short circuit
across the output terminals. Ch 1: Vout (5V/div). Ch 2: Iout (2A/div).
Figure 18: SYNC OUT vs. time, driving SYNC IN of a second SynQor
MQFL converter. Ch1: SYNC OUT: (1V/div).
Product# MQFL-28V-28S
Phone 1-888-567-9596
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Doc.# 005-0005081 Rev. G
05/27/15
Page 8
MQFL-28V-28S
Output: 28V
Current: 3.3A
Technical Figures
1
0
Forward Transmission (dB)
Output Impedance (ohms)
-10
0.1
0.01
16Vin
28Vin
40Vin
-20
-30
-40
-50
-60
-70
16Vin
28Vin
-80
40Vin
-90
0.001
10
100
1,000
Hz
10,000
10
100,000
Figure 19: Magnitude of incremental output impedance (Zout = vout/iout)
for minimum, nominal, and maximum input voltage at full rated power.
100
1,000
Hz
10,000
100,000
Figure 20: Magnitude of incremental forward transmission (FT = vout/
vin) for minimum, nominal, and maximum input voltage at full rated
power.
100
10
Input Impedance (ohms)
Reverse Transmission (dB)
0
-10
-20
-30
16Vin
-40
10
1
16Vin
28Vin
40Vin
28Vin
40Vin
-50
10
100
1,000
10,000
100,000
0.1
10
Hz
100
1,000
Hz
10,000
100,000
Figure 21: Magnitude of incremental reverse transmission (RT = iin/iout)
for minimum, nominal, and maximum input voltage at full rated power.
Figure 22: Magnitude of incremental input impedance (Zin = vin/iin) for
minimum, nominal, and maximum input voltage at full rated power.
Figure 23: High frequency conducted emissions of standalone MQFL28-05S, 5Vout module at 120W output, as measured with Method CE102.
Limit line shown is the ‘Basic Curve’ for all applications with a 28V
source.
Figure 24: High frequency conducted emissions of MQFL-28-05S, 5Vout
module at 120W output with MQME-28-P filter, as measured with Method
CE102. Limit line shown is the ‘Basic Curve’ for all applications with a
28V source.
Product# MQFL-28V-28S
Phone 1-888-567-9596
www.SynQor.com
Doc.# 005-0005081 Rev. G
05/27/15
Page 9
MQFL-28V-28S
Output: 28V
Current: 3.3A
Application Section
BASIC OPERATION AND FEATURES
The MQFL DC/DC converter uses a two-stage power conversion
topology. The first, or regulation, stage is a buck-converter that
keeps the output voltage constant over variations in line, load,
and temperature. The second, or isolation, stage uses transformers to provide the functions of input/output isolation and
voltage transformation to achieve the output voltage required.
In the MQFL-28V series of converters the regulation stage is
preceeded by a boost-converter that permits these converters
to operate through various Military and Aircraft under-voltage
transients. Further discussion of this feature can be found later
in these notes.
Both the regulation and the isolation stages switch at a fixed
frequency for predictable EMI performance. The isolation stage
switches at one half the frequency of the regulation stage, but
due to the push-pull nature of this stage it creates a ripple at
double its switching frequency. As a result, both the input and
the output of the converter have a fundamental ripple frequency
of about 550 kHz in the free-running mode.
Rectification of the isolation stage’s output is accomplished with
synchronous rectifiers. These devices, which are MOSFETs
with a very low resistance, dissipate far less energy than would
Schottky diodes. This is the primary reason why the MQFL
converters have such high efficiency, particularly at low output
voltages.
Besides improving efficiency, the synchronous rectifiers permit
operation down to zero load current. There is no longer a need
for a minimum load, as is typical for converters that use diodes
for rectification. The synchronous rectifiers actually permit a
negative load current to flow back into the converter’s output
terminals if the load is a source of short or long term energy.
The MQFL converters employ a “back-drive current limit” to
keep this negative output terminal current small.
There is a control circuit on both the input and output sides
of the MQFL converter that determines the conduction state
of the power switches. These circuits communicate with each
other across the isolation barrier through a magnetically coupled
device. No opto-isolators are used.
A separate bias supply provides power to both the input and
output control circuits. Among other things, this bias supply
permits the converter to operate indefinitely into a short circuit
and to avoid a hiccup mode, even under a tough start-up condition.
An input under-voltage lockout feature with hysteresis is provided, as well as an input over-voltage shutdown. There is also
an output current limit that is nearly constant as the load impedance decreases to a short circuit (i.e., there is not fold-back
or fold-forward characteristic to the output current under this
Product# MQFL-28V-28S
Phone 1-888-567-9596
condition). When a load fault is removed, the output voltage
rises exponentially to its nominal value without an overshoot.
The MQFL converter’s control circuit does not implement an output over-voltage limit or an over-temperature shutdown.
The following sections describe the use and operation of additional control features provided by the MQFL converter.
UNDER-VOLTAGE TRANSIENTS
The MQFL-28V series of DC/DC converters incorporate a special
“boost-converter” stage that permits the converters to deliver
full power through transients where its input voltage falls to as
low as 5.5V. Normally, the boost-converter is non-operational,
and the converter’s input voltage is passed directly to its preregulation stage (see the Block Diagram). When an under-voltage transient occurs, the boost-converter becomes operational,
and it steps-up the input voltage to a value greater than 16V so
that the nominal output voltage can be sustained.
It is important to note that the boost-converter stage must first
become “armed” before it can become operational. This “arming” occurs when the converter’s input voltage exceeds approximately 18V. The boost-converter then becomes operational
whenever the input voltage drops below the arming voltage, and
it will remain operational as long as the input voltage remains
within the region shown in the Under-Voltage Transient Profile
Page. If the input voltage drops below this transient profile, the
boost- converter stage is not guaranteed to continue operating
(it may, but it will protect itself from excessive stresses). Once
the boost- converter stops operating, the converter’s input voltage will be reconnected directly to the input of the pre-regulator
stage. The output voltage will therefore collapse unless the
input voltage is 16V, or greater.
Note: the boost-converter will not become re-armed for the next
transient unless the input voltage once again exceeds approximately 18V.
The transient profile shown on the Under-Voltage Transient
Profile page is designed to comply (with appropriate margins)
with all initial-engagement surges, starting or cranking voltage
transients, and under-voltage surges specified in:
•MIL-STD-704-8(AthroughF)
•RTCA/DO-160
•MIL-STD-1275
•DEF-STAN61-5(Part6)/5(operationalportions)
Any input voltage transient that fits within the Under-Voltage
Transient Profile can be repeated after a delay that is at least
four times longer than the duration of the previous transient.
During the time when the boost-converter stage is operational,
the converter’s efficiency is reduced and the input ripple cur-
www.SynQor.com
Doc.# 005-0005081 Rev. G
05/27/15
Page 10
MQFL-28V-28S
Output: 28V
Current: 3.3A
Application Section
rent is increased. The lower the input voltage, the more these
parameters are affected.
mits the converter to be inhibited from either the input or the
output side.
Usually the converter has an EMI filter upstream of it, and the
source voltage is connected to the input of this EMI filter. When,
during compliance testing, the source voltage goes low during
an under-voltage transient, the input to the converter will go
even lower. This is because the inductance of the EMI filter (as
well as the parasitic source inductance) will cause an oscillatory ring with the bulk capacitor. With the bulk capacitor that
is present in an MQME-28 filter, the peak of this under-voltage
ring may be approximately 2 volts if the source voltage drops
to 6V (it will be smaller than this at a higher transient source
voltage due to the lower current drawn by the converter). As
a result, it is necessary to add extra bulk capacitor across the
converter’s input pins if the source voltage is going to drop
to 6V, as it does for MIL-STD-704(A) or MIL-STD-1275D. It is
recommendedthata100μF/0.25WESRcapacitorbeconnected
across the input pins of the converter be used as a starting
point. For MIL-STD-704(B-F), where the source voltage drops
toonly7V,a47μFhold-upcapacitorwouldbeagoodstarting
point. The exact amount of capacitance required depends on
the application (source induc- tance, load power, rate of fall of
the source voltage, etc). Please consult the factory if further
assistance is required.
Regardless of which pin is used to inhibit the converter, the
regulation and the isolation stages are turned off. However,
when the converter is inhibited through the ENA1 pin, the bias
supply is also turned off, whereas this supply remains on when
the converter is inhibited through the ENA2 pin. A higher input
standby current therefore results in the latter case.
Because input system stability is harder to maintain as the
input voltage gets lower, the MQFL-28V series converters are
designed to give external access to the voltage node between
the boost-con- verter and the pre-regulator stages. This access,
at the “STABILITY” pin (pin 3), permits the user to add a stabilizing bulk capacitor with series resistance to this node. Since the
voltage at this node stays above 16V, the amount of capacitance
required is much less than would be required on the converter’s
input pins where the voltage might drop as low as 5.5V. It is
recommendedthata22μFcapacitorwithanESRofabout1W be
connected between the STABILITY pin and the INPUT RETURN
pin (pin 2). Without this special connection to the internal node
oftheconverter,a300μFstabilizingbulkcapacitorwouldhave
been required across the converter’s input pins.
Another advantage of the STABILITY pin is that it provides a
volt- age source that stays above 16V when the under-voltage
transient occurs. This voltage source might be useful for other
circuitry in the system.
CONTROL FEATURES
ENABLE: The MQFL converter has two enable pins. Both must
have a logic high level for the converter to be enabled. A logic
low on either pin will inhibit the converter.
TheENA1pin(pin4)isreferencedwithrespecttotheconverter’s input return (pin 2). The ENA2 pin (pin 12) is referenced
with respect to the converter’s output return (pin 8). This perProduct# MQFL-28V-28S
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5.6V
PIN 4
(OR PIN 12)
1N4148
82K
TO ENABLE
CIRCUITRY
ENABLE
250K
2N3904
125K
PIN 2
(OR PIN 8)
IN RTN
Figure A: Circuit diagram shown for reference only, actual circuit
components may differ from values shown for equivalent circuit.
Both enable pins are internally pulled high so that an open connection on both pins will enable the converter. Figure A shows
the equivalent circuit looking into either enable pins. It is TTL
compatible.
SHUT DOWN: The MQFL converter will shut down in response
to only four conditions: ENA1 input low, ENA2 input low, VIN
input below under-voltage lockout threshold, or VIN input above
over-voltage shutdown threshold. Following a shutdown event,
there is a startup inhibit delay which will prevent the converter
from restarting for approximately 300ms. After the 300ms delay
elapses, if the enable inputs are high and the input voltage is
within the operating range, the converter will restart. If the VIN
input is brought down to nearly 0V and back into the operating
range, there is no startup inhibit, and the output voltage will
rise according to the “Turn-On Delay, Rising Vin” specification.
REMOTE SENSE: The purpose of the remote sense pins is
to correct for the voltage drop along the conductors that connect the converter’s output to the load. To achieve this goal, a
separate conductor should be used to connect the +SENSE pin
(pin 10) directly to the positive terminal of the load, as shown
in the connection diagram on Page 2. Similarly, the –SENSE
pin (pin 9) should be connected through a separate conductor
to the return terminal of the load.
NOTE: Even if remote sensing of the load voltage is not desired,
the +SENSE and the -SENSE pins must be connected to +Vout
(pin7)andOUTPUTRETURN(pin8),respectively,togetproper
www.SynQor.com
Doc.# 005-0005081 Rev. G
05/27/15
Page 11
MQFL-28V-28S
Output: 28V
Current: 3.3A
Application Section
regulation of the converter’s output. If they are left open, the
converter will have an output voltage that is approximately
200mV higher than its specified value. If only the +SENSE pin
is left open, the output voltage will be approximately 25mV too
high.
Inside the converter, +SENSE is connected to +Vout with a
resistor value from 100W to 301W, depending on output voltage, and –SENSE is connected to OUTPUT RETURN with a 10W
resistor.
It is also important to note that when remote sense is used, the
voltage across the converter’s output terminals (pins 7 and 8)
will be higher than the converter’s nominal output voltage due
to resistive drops along the connecting wires. This higher voltage at the terminals produces a greater voltage stress on the
converter’s internal components and may cause the converter
to fail to deliver the desired output voltage at the low end of
the input voltage range at the higher end of the load current
and temperature range. Please consult the factory for details.
SYNCHRONIZATION: The MQFL converter’s regulation and
isolation stage switching frequencies can be synchronized to
an external frequency source that is in the 500 kHz to 600 kHz
range.Theboost-converterstageisfree-runningatabout670
kHz while it is operational, and is not affected by synchronization signals. A pulse train at the desired frequency should be
applied to the SYNC IN pin (pin 6) with respect to the INPUT
RETURN (pin 2). This pulse train should have a duty cycle in the
20% to 80% range. Its low value should be below 0.8V to be
guaranteed to be interpreted as a logic low, and its high value
should be above 2.0V to be guaranteed to be interpreted as a
logic high. The transition time between the two states should
be less than 300ns.
If the MQFL converter is not to be synchronized, the SYNC IN
pin should be left open circuit. The converter will then operate in
its free-running mode at a frequency of approximately 550 kHz.
If, due to a fault, the SYNC IN pin is held in either a logic low
or logic high state continuously, the MQFL converter will revert
to its free-running frequency.
The MQFL converter also has a SYNC OUT pin (pin 5). This
output can be used to drive the SYNC IN pins of as many as ten
(10) other MQFL converters. The pulse train coming out of SYNC
OUT has a duty cycle of 50% and a frequency that matches the
switching frequency of the converter with which it is associated.
This frequency is either the free-running frequency if there is no
synchronization signal at the SYNC IN pin, or the synchronization frequency if there is.
The SYNC OUT signal is available only when the voltage at the
STABILITY pin (pin 3) is above approximately 12V and when
the converter is not inhibited through the ENA1 pin. An inhibit
through the ENA2 pin will not turn the SYNC OUT signal off.
Product# MQFL-28V-28S
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NOTE: An MQFL converter that has its SYNC IN pin driven by
the SYNC OUT pin of a second MQFL converter will have its start
of its switching cycle delayed approximately 180 degrees relative to that of the second converter.
Figure B shows the equivalent circuit looking into the SYNC IN
pin. Figure C shows the equivalent circuit looking into the
SYNC OUT pin.
5V
5K
PIN 6
PIN 2
SYNC IN
TO SYNC
CIRCUITRY
5K
IN RTN
Figure B: Equivalent circuit looking into the SYNC IN pin with
respect to the IN RTN (input return) pin.
5V
5K
SYNC OUT
FROM SYNC
CIRCUITRY
IN RTN
OPEN COLLECTOR
OUTPUT
PIN 5
PIN 2
Figure C: Equivalent circuit looking into SYNC OUT pin with
respect to the IN RTN (input return) pin.
CURRENT SHARE: When several MQFL converters are placed
in parallel to achieve either a higher total load power or N+1
redundancy, their SHARE pins (pin 11) should be connected
together. The voltage on this common SHARE node represents
the average current delivered by all of the paralleled converters.
Each converter monitors this average value and adjusts itself so
that its output current closely matches that of the average.
Since the SHARE pin is monitored with respect to the OUTPUT
RETURN (pin 8) by each converter, it is important to connect
all of the converters’ OUTPUT RETURN pins together through a
low DC and AC impedance. When this is done correctly, the
converters will deliver their appropriate fraction of the total load
current to within +/- 10% at full rated load.
www.SynQor.com
Doc.# 005-0005081 Rev. G
05/27/15
Page 12
MQFL-28V-28S
Output: 28V
Current: 3.3A
Application Section
100,000
NOTE: Converters operating from separate input filters with
reverse polarity protection (such as the MQME-28-T filter) with
their outputs connected in parallel may exhibit hiccup operation
at light loads. Consult factory for details.
OUTPUT VOLTAGE TRIM: If desired, it is possible to increase
the MQFL converter’s output voltage above its nominal value.
To do this, use the +SENSE pin (pin 10) for this trim function
instead of for its normal remote sense function, as shown in
Figure D. In this case, a resistor connects the +SENSE pin to
the –SENSE pin (which should still be connected to the output
return, either remotely or locally). The value of the trim resistor
should be chosen according to the following equation or from
Figure E:
Vnom
Rtrim = 100 x
Vout - Vnom - 0.025
where:
Vnom = the converter’s nominal output voltage,
Vout = the desired output voltage (greater than Vnom), and
Rtrim is in Ohms.
As the output voltage is trimmed up, it produces a greater
voltage stress on the converter’s internal components and may
cause the converter to fail to deliver the desired output voltage
External bulk capacitor
28 Vdc
+
_
RSTABILITY
CSTABILITY
open
means
on
1
+VIN
2
IN RTN
3
STABILITY
4
ENA 1
5
SYNC OUT
6
SYNC IN
Trim Resistance (ohms)
Whether or not converters are paralleled, the voltage at the
SHARE pin could be used to monitor the approximate average current delivered by the converter(s). A nominal voltage
of 1.0V represents zero current and a nominal voltage of 2.2V
represents the maximum rated current, with a linear relationship
in between. The internal source resistance of a converter’s
SHARE pin signal is 2.5 kW. During an input voltage fault or
primary disable event, the SHARE pin outputs a power failure
warning pulse. The SHARE pin will go to 3V for approximately
14msastheoutputvoltagefalls.
10,000
1,000
100
0
0.5
1
1.5
2
2.5
3
Increase in Vout (V)
Figure E: Output Voltage Trim Graph
at the low end of the input voltage range at the higher end of
the load current and temperature range. Please consult the
factory for details.
INPUT UNDER-VOLTAGE LOCKOUT: The MQFL converter
has an under-voltage lockout feature that ensures the converter will be off if the input voltage is too low. This lockout
only appears when the boost-converter is not operating. The
threshold of input voltage at which the converter will turn on is
higher that the threshold at which it will turn off. In addition, the
MQFL converter will not respond to a state of the input voltage
unlessithasremainedinthatstateformorethanabout200μs.
This hysteresis and the delay ensure proper operation when the
source impedance is high or in a noisy environment.
INPUT OVER-VOLTAGE SHUTDOWN: The MQFL converter
also has an over-voltage feature that ensures the converter will
be off if the input voltage is too high. It also has a hysteresis
and time delay to ensure proper operation.
ENA 2 12
SHARE 11
MQFL
+SNS 10
-SNS 9
RTRIM
_
OUT RTN 8
+VOUT 7
Load
+
Figure D: Typical connection for output voltage trimming.
Product# MQFL-28V-28S
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Doc.# 005-0005081 Rev. G
05/27/15
Page 13
MQFL-28V-28S
Output: 28V
Current: 3.3A
Application Section
BACK-DRIVE CURRENT LIMIT: Converters that use MOSFETs
as synchronous rectifiers are capable of drawing a negative current from the load if the load is a source of short- or long-term
energy. This negative current is referred to as a “back-drive
current”.
Conditions where back-drive current might occur include paralleled converters that do not employ current sharing, or where
the current share feature does not adequately ensure sharing
during the startup or shutdown transitions. It can also occur
when converters having different output voltages are connected
together through either explicit or parasitic diodes that, while
normally off, become conductive during startup or shutdown.
Finally, some loads, such as motors, can return energy to their
power rail. Even a load capacitor is a source of back-drive
energy for some period of time during a shutdown transient.
To avoid any problems that might arise due to back-drive current, the MQFL converters limit the negative current that the
converter can draw from its output terminals. The threshold
for this back-drive current limit is placed sufficiently below zero
so that the converter may operate properly down to zero load,
but its absolute value (see the Electrical Characteristics page) is
small compared to the converter’s rated output current.
When the converter is mounted on a metal plate, the plate will
help to make the converter’s case bottom a uniform temperature. How well it does so depends on the thickness of the plate
and on the thermal conductance of the interface layer (e.g. thermal grease, thermal pad, etc.) between the case and the plate.
Unless this is done very well, it is important not to mistake the
plate’s temperature for the maximum case temperature. It is
easy for them to be as much as 5-10ºC different at full power
and at high temperatures. It is suggested that a thermocouple
be attached directly to the converter’s case through a small hole
in the plate when investigating how hot the converter is getting.
Care must also be made to ensure that there is not a large
thermal resistance between the thermocouple and the case due
to whatever adhesive might be used to hold the thermocouple
in place.
INPUT SYSTEM INSTABILITY: This condition can occur
because any DC/DC converter appears incrementally as a
negative resistance load. A detailed application note titled
“Input System Instability” is available on the SynQor website
which provides an understanding of why this instability arises,
and shows the preferred solution for correcting it.
THERMAL CONSIDERATIONS: Figure 5 shows the
suggested Power Derating Curves for this converter as
a function of the case temperature and the maximum
desired power MOSFET junction temperature. All other
components within the converter are cooler than its hottest
MOSFET, which at full power is no more than 20ºC higher
than the case temperature directly below this MOSFET.
The Mil-HDBK-1547A component derating guideline calls
for a maximum component temperature of 105ºC. Figure 5
therefore has one power derating curve that ensures this limit
is maintained. It has been SynQor’s extensive experience that
reliable long-term converter operation can be achieved with
a maximum component temperature of 125ºC. In extreme
cases,amaximumtemperatureof145ºCispermissible,butnot
recommended for long-term operation where high reliability is
required. Derating curves for these higher temperature limits
are also included in Figure 5. The maximum case temperature
at which the converter should be operated is 135ºC.
Product# MQFL-28V-28S
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Doc.# 005-0005081 Rev. G
05/27/15
Page 14
MQFL-28V-28S
Output: 28V
Current: 3.3A
Stress Screening
CONSTRUCTION AND ENVIRONMENTAL STRESS SCREENING OPTIONS
Consistent with
MIL-STD-883F
Screening
C-Grade
ES-Grade
from
( specified
0 °C to +70 °C )
Element Evaluation
HB-Grade
from
from
( -45specified
( -55specified
°C to +100 °C )
°C to +125 °C )
No
Yes
Yes
Yes
Yes
Internal Visual
*
Yes
Temperature Cycle
Method 1010
No
Constant Acceleration
Method 2001
(Y1 Direction)
No
500g
Condition A
(5000g)
Burn-in
Method 1015
24 Hrs @ +125 °C
96 Hrs @ +125 °C
160 Hrs @ +125 °C
Final Electrical Test
Method 5005 (Group A)
+25 °C
-45, +25, +100 °C
-55, +25, +125 °C
Full QorSeal
Full QorSeal
Full QorSeal
*
Yes
Yes
QorSeal
QorSeal
QorSeal
Mechanical Seal,
Thermal, and
Coating Process
External Visual
2009
Construction Process
Condition B
Condition C
(-55 °C to +125 °C) (-65 °C to +150 °C)
* Per IPC-A-610 Class 3
MilQor converters and filters are offered in three variations of environmental stress screening options. All MilQor converters use SynQor’s
proprietary QorSeal® Hi-Rel assembly process that includes a Parylene-C coating of the circuit, a high performance thermal compound filler, and a
nickel barrier gold plated aluminum case. Each successively higher grade has more stringent mechanical and electrical testing, as well as a longer
burn-in cycle. The ES- and HB-Grades are also constructed of components that have been procured through an element evaluation process that prequalifies each new batch of devices.
Product# MQFL-28V-28S
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Doc.# 005-0005081 Rev. G
05/27/15
Page 15
MQFL-28V-28S
Output: 28V
Current: 3.3A
Technical Specifications
MIL-STD-810F Qualification Testing
MIL-STD-810F Test
Fungus
Method
Description
508.5
Table 508.5-I
500.4 - Procedure I
Storage: 70,000ft. / 2 Hr. duration
500.4 - Procedure II
Operating; 70,000ft. / 2 Hr. duration; Ambient Temperature
Rapid Decompression
500.4 - Procedure III
Storage: 8,000ft. to 40,000ft.
Acceleration
513.5 - Procedure II
Operating - 15g’s
Salt Fog
509.4
Storage
501.4 - Procedure I
Storage: 135°C / 3 hrs
501.4 - Procedure II
Operating: 100°C / 3 hrs
502.4 - Procedure I
Storage: -65°C / 4 hrs
502.4 - Procedure II
Operating: -55°C / 3 hrs
Altitude
High Temperature
Low Temperature
Temperature Shock
503.4 - Procedure I - C Storage: -65°C to 135°C; 12 cycles
Rain
506.4 - Procedure I
Wind Blown Rain
Immersion
512.4 - Procedure I
Non-Operating
Humidity
507.4 - Procedure II
Random Vibration
514.5 - Procedure I
10-2000 Hz, PSD level of 1.5 g2/Hz(54.6grms), duration = 1 hr/axis
516.5 - Procedure I
20g’s peak, 11ms, Functional Shock (Operating no load) (saw tooth)
516.5 - Procedure VI
Bench Handling Shock
Shock
Sinusoidal vibration
Sand and Dust
Product# MQFL-28V-28S
514.5 - Category 14
Aggravated cycle @ 95% RH (Figure 507.5-7 aggravated temp humidity cycle, 15 cycles)
Rotary wing aircraft - helicopter, 4hrs/axis, 20g’s (sine sweep from 10 500HZ)
510.4 - Procedure I
Blowing Dust
510.4 - Procedure II
Blowing Sand
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Doc.# 005-0005081 Rev. G
05/27/15
Page 16
MQFL-28V-28S
Output: 28V
Current: 3.3A
Technical Specifications
First Article Testing consistent with MIL-STD-883F
MIL-STD-883F Test
Method
Description
Electrical Tests
5005
Physical Dimensions test
2016
Resistance to Solvents test
2015.13
Solderability test
2003.8
Lead Integrity test
2004.5
Salt Atmosphere test
1009.8
Adhesion of Lead Finish test
2025.4
Altitude Operation test
1001
Condition “C”
ESD Sensitivity
3015.7
Class 2
Stabilization Bake test
1008.2
Condition “C”
Vibration Fatigue test
2005.2
Condition “A”
Random Vibration test
2026
Condition “II K”
Condition “A”
Sequential Test Group #1
Life Test – Steady State test
1005.8
Life Test – Intermittent Duty test
1006
Sequential Test Group #2
Temperature Cycle test
1010.8
Condition “C”
Constant Acceleration test
2001.2
Condition “A”
Thermal Shock test
1011.9
Condition “B”
Temperature Cycle test
1010.8
Condition “C”
Moisture Resistance test
1004.7
With Sub cycle
Mechanical Shock test
2002.4
Condition “B”
Variable Frequency Vibration test
2007.3
Condition “A”
Sequential Test Group #3
Sequential Test Group #4
Product# MQFL-28V-28S
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Doc.# 005-0005081 Rev. G
05/27/15
Page 17
MQFL-28V-28S
Output: 28V
Current: 3.3A
Mechanical Diagrams
1
2
3
4
5
6
SEE NOTE 7
+VIN
IN RTN
SHARE
STABILITY
MQFL-28V-28S-X-ES
+SNS
DC-DC ConVErtEr
28Vin 28Vout @ 3.3A
ENA 1
-SNS
SYNC OUT
SYNC IN
12
11
10
9
8
7
ENA 2
MADE IN USA
OUT RTN
S/N 0000000 D/C 3205-301 CAGE 1WX10
+VOUT
0.250 [6.35]
1.50 [38.1]
0.040 [1.02]
PIN
2.50 [63.50]
2.760 [70.10]
3.00 [76.2]
0.22 [5.6]
0.228 [5.79]
0.390 [9.91]
SEE NOTE 7
6
+VIN
ENA 2
IN RTN
STABILITY
SHARE
MQFL-28V-28S-U-ES
+SNS
DC-DC ConVErtEr
28Vin 28Vout @ 3.3A
ENA 1
SYNC OUT
SYNC IN
0.050 [1.27]
0.128 [3.25]
2.96 [75.2]
1
2
3
4
5
0.200 [5.08]
TYP. NON-CUM.
1.260
[32.00]
-SNS
MADE IN USA
S/N 0000000 D/C 3211-301 CAGE 1WX10
OUT RTN
+VOUT
12
11
10
9
8
7
2.50 [63.5]
2.760 [70.10]
3.00 [76.2]
Case X
0.250 [6.35]
0.200 [5.08]
TYP.
NON-CUM.
1.50 [38.1]
1.260
[32.00]
0.040
[1.02]
PIN
0.050 [1.27]
0.42
[10.7]
0.128 [3.25]
0.22 [5.6]
2.80 [71.1]
0.390 [9.91]
PIN DESIGNATIONS
NOTES
1)
2)
3)
4)
5)
6)
7)
8)
Pins 0.040’’ (1.02mm) diameter
Pin Material: Copper Alloy
Finish: Gold over Nickel plating, followed by Sn/Pb solder dip
All dimensions in inches (mm) Tolerances: x.xx +/-0.02 in. (x.x +/-0.5mm)
x.xxx +/-0.010 in. (x.xx +/-0.25mm)
Weight: 2.8 oz (78.5 g) typical
Workmanship: Meets or exceeds IPC-A-610 Class III
Print Labeling on Top Surface per Product Label Format Drawing
Pin 1 identification hole, not intended for mounting (case X and U)
Baseplate flatness tolerance is 0.004” (.10mm) TIR for surface.
Product# MQFL-28V-28S
Case U
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Pin # Function
1
2
3
4
5
6
Pin # Function
Positive input
Input return
Stability
Enable 1
Sync output
Sync input
Doc.# 005-0005081 Rev. G
7
8
9
10
11
12
Positive output
Output return
- Sense
+ Sense
Share
Enable 2
05/27/15
Page 18
MQFL-28V-28S
Output: 28V
Current: 3.3A
Mechanical Diagrams
0.300 [7.62]
0.140 [3.56]
1.150 [29.21]
0.250 [6.35]
TYP
1
2
3
4
5
6
+VIN
ENA 2
IN RTN
SHARE
MQFL-28V-28S-Y-ES
STABILITY
ENA 1
-SNS
SYNC OUT
SYNC IN
+SNS
DC-DC ConVErtEr
28Vin 28Vout @ 3.3A
MADE IN USA
S/N 0000000 D/C 3211-301 CAGE 1WX10
OUT RTN
+VOUT
1.750 [44.45]
12
2.000
11
[50.80]
10
1.50
9 [38.1]
8
1.750
7
[44.45]
0.250 [6.35]
0.200 [5.08]
TYP. NON-CUM.
0.040 [1.02]
PIN
0.050 [1.27]
0.22 [5.6]
0.375 [9.52]
2.50 [63.5]
2.96 [75.2]
0.228 [5.79]
0.390 [9.91]
Case Y
Case Z
(variant of Y)
0.250 [6.35]
Case W
(variant of Y)
0.250 [6.35]
0.200 [5.08]
TYP. NON-CUM.
0.200 [5.08]
TYP. NON-CUM.
0.040 [1.02]
PIN
0.040 [1.02]
PIN
0.22 [5.6]
0.050 [1.27]
0.42 [10.7]
0.36 [9.14]
0.050 [1.27]
0.22 [5.6]
2.80 [71.1]
0.525 [13.33]
0.390
[9.91]
0.525 [13.33]
0.390
[9.91]
2.80 [71.1]
PIN DESIGNATIONS
NOTES
1)
2)
3)
4)
5)
6)
7)
8)
Pins 0.040’’ (1.02mm) diameter
Pin Material: Copper Alloy
Finish: Gold over Nickel plating, followed by Sn/Pb solder dip
All dimensions in inches (mm) Tolerances: x.xx +/-0.02 in. (x.x +/-0.5mm)
x.xxx +/-0.010 in. (x.xx +/-0.25mm)
Weight: 2.8 oz (78.5 g) typical
Workmanship: Meets or exceeds IPC-A-610 Class III
Print Labeling on Top Surface per Product Label Format Drawing
Pin 1 identification hole, not intended for mounting (case X and U)
Baseplate flatness tolerance is 0.004” (.10mm) TIR for surface.
Product# MQFL-28V-28S
Phone 1-888-567-9596
www.SynQor.com
Pin # Function
1
2
3
4
5
6
Pin # Function
Positive input
Input return
Stability
Enable 1
Sync output
Sync input
Doc.# 005-0005081 Rev. G
7
8
9
10
11
12
Positive output
Output return
- Sense
+ Sense
Share
Enable 2
05/27/15
Page 19
MQFL-28V-28S
Output: 28V
Current: 3.3A
Ordering Information
MilQor Converter FAMILY MATRIX
The tables below show the array of MilQor converters available. When ordering SynQor converters, please ensure that
you use the complete part number according to the table in the last page. Contact the factory for other requirements.
Single Output
Full Size
MQFL-28
16-40Vin Cont.
16-50Vin 1s Trans.*
Dual Output †
1.5V
(1R5S)
1.8V
(1R8S)
2.5V
(2R5S)
3.3V
(3R3S)
5V
(05S)
6V
(06S)
7.5V
(7R5S)
9V
(09S)
12V
(12S)
15V
(15S)
28V
(28S)
5V
(05D)
12V
(12D)
15V
(15D)
40A
40A
40A
30A
24A
20A
16A
13A
10A
8A
4A
24A
Total
10A
Total
8A
Total
40A
40A
40A
30A
24A
20A
16A
13A
10A
8A
4A
24A
Total
10A
Total
8A
Total
40A
40A
40A
30A
20A
17A
13A
11A
8A
6.5A
3.3A
40A
40A
40A
30A
20A
17A
13A
11A
8A
6.5A
3.3A
40A
40A
40A
30A
24A
20A
16A
13A
10A
8A
4A
24A
Total
10A
Total
8A
Total
40A
40A
30A
22A
15A
12A
10A
8A
6A
5A
2.7A
15A
Total
6A
Total
5A
Total
1.5V
(1R5S)
1.8V
(1R8S)
2.5V
(2R5S)
3.3V
(3R3S)
5V
(05S)
6V
(06S)
7.5V
(7R5S)
9V
(09S)
12V
(12S)
15V
(15S)
28V
(28S)
5V
(05D)
12V
(12D)
15V
(15D)
20A
20A
20A
15A
10A
8A
6.6A
5.5A
4A
3.3A
1.8A
10A
Total
4A
Total
3.3A
Total
20A
20A
20A
15A
10A
8A
6.6A
5.5A
4A
3.3A
1.8A
10A
Total
4A
Total
3.3A
Total
10A
10A
10A
7.5A
5A
4A
3.3A
2.75A
2A
1.65A
0.9A
5A
Total
2A
Total
1.65A
Total
10A
10A
10A
7.5A
5A
4A
3.3A
2.75A
2A
1.65A
0.9A
5A
Total
2A
Total
1.65A
Total
Absolute Max Vin = 60V
MQFL-28E
16-70Vin Cont.
16-80Vin 1s Trans.*
Absolute Max Vin =100V
MQFL-28V
16-40Vin Cont.
5.5-50Vin 1s Trans.*
Absolute Max Vin = 60V
MQFL-28VE
16-70Vin Cont.
5.5-80Vin 1s Trans.*
Absolute Max Vin = 100V
MQFL-270
155-400Vin Cont.
155-475Vin 1s Trans.*
Absolute Max Vin = 550V
MQFL-270L
65-350Vin Cont.
65-475Vin 1s Trans.*
Absolute Max Vin = 550V
Single Output
Half Size
MQHL-28
16-40Vin Cont.
16-50Vin 1s Trans.*
Dual Output †
Absolute Max Vin = 60V
MQHL-28E
16-70Vin Cont.
16-80Vin 1s Trans.*
Absolute Max Vin =100V
MQHR-28
16-40Vin Cont.
16-50Vin 1s Trans.*
Absolute Max Vin = 60V
MQHR-28E
16-70Vin Cont.
16-80Vin 1s Trans.*
Absolute Max Vin = 100V
Check with factory for availability.
†80% of total output current available on any one output.
*Converters may be operated at the highest transient input voltage, but some component electrical and thermal stresses would be beyond MILHDBK-1547A guidelines.
Product# MQFL-28V-28S
Phone 1-888-567-9596
www.SynQor.com
Doc.# 005-0005081 Rev. G
05/27/15
Page 20
MQFL-28V-28S
Output: 28V
Current: 3.3A
Ordering Information
PART NUMBERING SYSTEM
The part numbering system for SynQor’s MilQor DC-DC converters follows the format shown in the table below.
Not all combinations make valid part numbers, please contact SynQor for availability. See the Product Summary web page for more options.
Example:
Input
Voltage
Range
Model
Name
28
28E
28V
28VE
MQFL
MQHL
MQHR
270
270L
MQFL-28V-28S-Y-ES
Output Voltage(s)
Single
Output
Dual
Output
1R5S
1R8S
2R5S
3R3S
05S
06S
7R5S
09S
12S
15S
28S
05D
12D
15D
Package Outline/
Pin Configuration
Screening
Grade
U
X
Y
W
Z
C
ES
HB
APPLICATION NOTES
A variety of application notes and technical white papers can be downloaded in pdf format from the SynQor website.
Contact SynQor for further information and to order:
Phone:
Toll Free:
Fax:
E-mail:
Web:
Address:
Product# MQFL-28V-28S
978-849-0600
1-888-567-9596
978-849-0602
[email protected]
www.synqor.com
155 Swanson Road
Boxborough, MA 01719
USA
Phone 1-888-567-9596
PATENTS
SynQor holds numerous U.S. patents, one or more of which apply to most of its power converter
products. Any that apply to the product(s) listed in this document are identified by markings on
the product(s) or on internal components of the product(s) in accordance with U.S. patent laws.
SynQor’s patents include the following:
5,999,417
6,222,742
6,545,890
6,594,159 6,731,520
6,894,468
6,896,526
6,927,987
7,050,309
7,072,190
7,085,146
7,119,524
7,269,034
7,272,021
7,272,023
7,558,083
7,564,702
7,765,687
7,787,261
8,023,290
8,149,597
8,493,751 8,644,027
Warranty
SynQor offers a two (2) year limited warranty. Complete warranty information
is listed on our website or is available upon request from SynQor.
www.SynQor.com
Doc.# 005-0005081 Rev. G
05/27/15
Page 21