SYNQOR MQFL-28E-2R5S

MQFL-28E-2R5S
Single Output
H IGH R ELIABILITY DC-DC C ONVERTER
16-80V
2.5V
40A
88% @ 20A / 87% @ 40A
Continuous Input
Transient Input
Output
Output
Efficiency
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16-70V
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 QorSealTM packaging approach ensures
survivability in the most hostile environments. Compatible
with the industry standard format, these converters operate
B
Y-H
5S-
at a fixed frequency, have no opto-isolators, and follow
2R
8E-
2
ter
ver 0A
on t @ 4
C
u
C
o
D
/
V
DC in 2.5
28V
FL-
MQ
conservative component derating guidelines. They are
designed and manufactured to comply with a wide range of
military standards.
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
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 lockout/over-voltage shutdown
Specification Compliance
In-Line Manufacturing Process
•
•
•
•
•
•
AS9100 and ISO 9001:2000 certified facility
Full component traceability
Temperature cycling
Constant acceleration
24, 96, 160 hour burn-in
Three level temperature screening
Product # MQFL-28E-2R5S
Phone 1-888-567-9596
MQFL series converters (with MQME filter) are designed to meet:
• MIL-HDBK-704-8 (A through F)
• RTCA/DO-160E Section 16
• MIL-STD-1275B
• DEF-STAN 61-5 (part 6)/5
• MIL-STD-461 (C, D, E)
• RTCA/DO-160E Section 22
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Doc.# 005-0005142 Rev. 2
04/30/09
Page 1
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
Technical Specification
BLOCK DIAGRAM
7
ISOLATION STAGE
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REGULATION STAGE
CURRENT
SENSE
1
POSITIVE
INPUT
T1
T2
T1
POSITIVE
OUTPUT
T2
2
8
INPUT
RETURN
ISOLATION BARRIER
OUTPUT
RETURN
3
CASE
GATE DRIVERS
UVLO
OVSD
CURRENT
LIMIT
4
GATE DRIVERS
12
ENABLE 2
11
MAGnEtIC
ENABLE 1
PRIMARY
CONTROL
5
SECONDARY
CONTROL
SHARE
10
DAtA COUPLInG
SYNC OUTPUT
+ SENSE
6
9
SYNC INPUT
- SENSE
BIAS POWER
CONTROL
POWER
tRAnSFORMER
TYPICAL CONNECTION DIAGRAM
1
2
3
28 Vdc
4
+
–
5
open
means
on
Product # MQFL-28E-2R5S
6
+VIN
ENA 2
IN RTN
SHARE
CASE
+ SNS
ENA 1
MQFL
SYNC OUT
OUT RTN
SYNC IN
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– SNS
+VOUT
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12
11
open
means
on
10
9
+
Load
8
–
7
Doc.# 005-0005142 Rev. 2
04/30/09
Page 2
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
Technical Specification
MQFL-28E-2R5S ELECTRICAL CHARACTERISTICS
Parameter
Min. Typ. Max. Units Notes & Conditions
Group A
Subgroup
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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)
Output 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 = 40A (16Vin)
Iout = 20A (16Vin)
Iout = 40A (28Vin)
Iout = 20A (28Vin)
Iout = 40A (40Vin)
Iout = 20A (40Vin)
Iout = 40A (70Vin)
Load Fault Power Dissipation
Short Circuit Power Dissipation
Vin=28V dc ±5%, Iout=40A, CL=0µF, free running (see Note 10)
unless otherwise specified
Product # MQFL-28E-2R5S
-500
-800
-55
-65
-1.2
100
100
-0.8
-1.2
V
V
V
V
500
800
135
135
300
50
V
V
°C
°C
°C
V
16
16
28
28
70
80
V
V
14.75
13.80
0.50
15.50
14.40
1.10
16.00
15.00
1.80
V
V
V
90
82
3
95
86
9
100
90
15
8
160
5
50
60
V
V
V
A
mA
mA
mA
mA
2.53
2.54
20
17
2.55
60
40
100
52
53
50
10,000
V
V
mV
mV
V
mV
A
W
A
A
A
mA
µF
-300
300
200
450
350
mV
mV
µs
250
250
250
500
mV
mV
µs
10
2
8.0
6.0
3.0
ms
%
ms
ms
ms
34
34
%
%
%
%
%
%
%
W
W
110
2
25
40
2.47
2.46
-20
7
2.45
0
0
41
41
-450
-250
-250
2.50
2.50
0
12
2.50
15
46
47
13
10
6
5.5
3.0
1.5
TBD
TBD
TBD
TBD
TBD
TBD
TBD
Phone 1-888-567-9596
87
89
87
88
85
87
82
19
20
www.synqor.com
See Note 1
See Note 2
Continuous
Transient, 1 s
See Note 3
1, 2, 3
4, 5, 6
1, 2, 3
1, 2, 3
1, 2, 3
See Note 15
Vin = 16V; Iout = 40A
Vin = 16V, 28V, 70V
Vin = 16V, 28V, 70V
Bandwidth = 100kHz – 10MHz; see Figure 14
Vout at sense leads
"
" ; Vin = 16V, 28V, 70V; Iout=40A
" ; Vout @ (Iout=0A) - Vout @ (Iout=40A)
"
Bandwidth = 10MHz; CL=11µF
See Note 4
Vout ≤ 1.2V
See Note 6
Total Iout step = 20A‹-›40A, 4A‹-›20A; CL=11µF
"
See Note 7
Vin step = 16V‹-›50V; CL=11µF; see Note 8
"
"
See Note 7
Vout = 0.25V-›2.25V
1
2, 3
1, 2, 3
1, 2, 3
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
4, 5, 6
4, 5, 6
4, 5, 6
4, 5, 6
4, 5, 6
See Note 5
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
Iout at current limit inception point; See Note 4
Vout ≤ 1.2V
Doc.# 005-0005142 Rev. 2
1,3
1,3
1,3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
04/30/09
1,
1,
1,
1,
1,
1,
1,
1,
1,
2,
2,
2,
2,
2,
2,
2,
2,
2,
3
3
3
3
3
3
3
3
3
Page 3
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
Technical Specification
MQFL-28E-2R5S ELECTRICAL CHARACTERISTICS (Continued)
Parameter
Min. Typ. Max. Units Notes & Conditions
Vin=28V dc ±5%, Iout=40A, CL=0µF, free running (see Note 10) unless
otherwise specified
Group A
Subgroup
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ISOLATION CHARACTERISTICS
Isolation Voltage
Dielectric strength
Input RTN to Output RTN
500
V
1
Any Input Pin to Case
500
V
1
Any Output Pin to Case
500
V
1
Isolation Resistance (in rtn to out rtn)
100
MΩ
1
Isolation Resistance (any pin to case)
100
MΩ
1
Isolation Capacitance (in rtn to out rtn)
44
nF
1
FEATURE CHARACTERISTICS
Switching Frequency (free running)
500
550
600
kHz
1, 2, 3
Synchronization Input
Frequency Range
500
700
kHz
1, 2, 3
Logic Level High
2.0
10
V
1, 2, 3
Logic Level Low
-0.5
0.8
V
1, 2, 3
Duty Cycle
20
80
%
See Note
Synchronization Output
Pull Down Current
20
mA
VSYNC OUT = 0.8V
See Note
Duty Cycle
25
75
%
Output connected to SYNC IN of other MQFL unit
See Note
Enable Control (ENA1 and ENA2)
Off-State Voltage
0.8
V
1, 2, 3
Module Off Pulldown Current
80
µA
Current drain required to ensure module is off
See Note
On-State Voltage
2
V
1, 2, 3
Module On Pin Leakage Current
20
µA
Imax drawn from pin allowed, module on
See Note
Pull-Up Voltage
3.2
4.0
4.5
V
See Figure A
1, 2, 3
RELIABILITY CHARACTERISTICS
Calculated MTBF (MIL-STD-217F2)
GB @ Tcase = 70ºC
2800
103 Hrs.
AIF @ Tcase = 70ºC
440
103 Hrs.
Demonstrated MTBF
TBD
103 Hrs.
WEIGHT CHARACTERISTICS
Device Weight
79
g
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).
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 ±50mV 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 100ºC.
15. Input Over Voltage Shutdown test is run at no load, full load is beyond derating condition and could cause damage at 125ºC.
Product # MQFL-28E-2R5S
Phone 1-888-567-9596
www.synqor.com
Doc.# 005-0005142 Rev. 2
04/30/09
5
5
5
5
5
Page 4
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
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Technical Specification
TBD
TBD
Figure 1: Efficiency at nominal output voltage vs. load current for
minimum, nominal, and maximum input voltage at Tcase=25°C.
Figure 2: Efficiency at nominal output voltage and 60% rated power vs.
case temperature for input voltage of 16V, 28V, 40V ,and 70V.
TBD
TBD
Figure 3: Power dissipation at nominal output voltage vs. load current
for minimum, nominal, and maximum input voltage at Tcase=25°C.
Figure 4: Power dissipation at nominal output voltage and 60% rated
power vs. case temperature for input voltage of 16V, 28V, 40V ,and 70V.
TBD
TBD
Figure 5: Output Current / Output Power derating curve as a
function of Tcase and the Maximum desired power MOSFET junction
temperature (see Note 14).
Product # MQFL-28E-2R5S
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Figure 6: Output voltage vs. load current showing typical current
limit curves.
www.synqor.com
Doc.# 005-0005142 Rev. 2
04/30/09
Page 5
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
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Technical Specification
TBD
TBD
Figure 7: Turn-on transient at full resistive load and zero output
capacitance initiated by ENA1. Input voltage pre-applied. Ch 1:
Vout (500mV/div). Ch 2: ENA1 (5V/div).
Figure 8: Turn-on transient at full resistive load and 10mF output
capacitance initiated by ENA1. Input voltage pre-applied. Ch 1:
Vout (500mV/div). Ch 2: ENA1 (5V/div).
TBD
TBD
Figure 9: Turn-on transient at full resistive load and zero output
capacitance initiated by ENA2. Input voltage pre-applied. Ch 1:
Vout (500mV/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 (500mV/div). Ch 2: Vin (10V/div).
TBD
TBD
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 (200mV/div). Ch 2: Iout
(20A/div).
Product # MQFL-28E-2R5S
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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 (200mV/div). Ch 2: Iout (20A/div).
www.synqor.com
Doc.# 005-0005142 Rev. 2
04/30/09
Page 6
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
Technical Specification
See Fig. 16
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See Fig. 15
MQME
Filter
TBD
iC
MQFL
Converter
VSOURCE
VOUT
1µF
ceramic
capacitor
10µF,
100mW
ESR
capacitor
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 (200mV/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).
TBD
TBD
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: 1μ F ceramic capacitor
and 10μF tantalum capacitor. Bandwidth: 10MHz. See Figure 14.
TBD
TBD
Figure 17: Rise of output voltage after the removal of a short
circuit across the output terminals. Ch 1: Vout (500mV/div). Ch 2:
Iout (20A/div).
Product # MQFL-28E-2R5S
Phone 1-888-567-9596
Figure 18: SYNC OUT vs. time, driving SYNC IN of a second SynQor
MQFL converter. Ch1: SYNC OUT: (1V/div).
www.synqor.com
Doc.# 005-0005142 Rev. 2
04/30/09
Page 7
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
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Technical Specification
TBD
TBD
Figure 19: Magnitude of incremental output impedance (Zout =
vout/iout) for minimum, nominal, and maximum input voltage at full
rated power.
Figure 20: Magnitude of incremental forward transmission (FT =
vout/vin) for minimum, nominal, and maximum input voltage at full
rated power.
TBD
TBD
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.
TBD
TBD
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.
Product # MQFL-28E-2R5S
Phone 1-888-567-9596
Figure 24: High frequency conducted emissions of MQFL-28-05S,
5Vout module at 120W output with MQFL-28-P filter, as measured
with Method CE102. Limit line shown is the ‘Basic Curve’ for all
applications with a 28V source.
www.synqor.com
Doc.# 005-0005142 Rev. 2
04/30/09
Page 8
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
Technical Specification
BASIC OPERATION AND 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.
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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.
CONTROL FEATURES
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 foldforward characteristic to the output current under this 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 ENA1 pin (pin 4) is referenced with respect to the converter’s
input return (pin 2). The ENA2 pin (pin 12) is referenced with
respect to the converter’s output return (pin 8). This permits the
converter to be inhibited from either the input or the output side.
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.
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.
5.6V
82K
1N4148
PIN 4
(or PIN 12)
ENABLE
TO ENABLE
CIRCUITRY
250K
2N3904
125K
PIN 2
(or PIN 8)
IN RTN
Figure A: Equivalent circuit looking into either the ENA1 or ENA2
pins with respect to its corresponding return pin.
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.
The following sections describe the use and operation of additional control features provided by the MQFL converter.
Product # MQFL-28E-2R5S
Phone 1-888-567-9596
www.synqor.com
Doc.# 005-0005142 Rev. 2
04/30/09
Page 9
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
Technical Specification
synchronization signal at the SYNC IN pin, or the synchronization frequency if there is.
The SYNC OUT signal is available only when the DC input voltage 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.
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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 (pin
7) and OUTPUT RETURN (pin 8), respectively, to get proper 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.
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
Inside the converter, +SENSE is connected to +Vout with a resistor value from 100W to 274W, 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 switching frequency can be synchronized to an external frequency source
that is in the 500 kHz to 700 kHz range. 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
Product # MQFL-28E-2R5S
Phone 1-888-567-9596
5K
TO SYNC
CIRCUITRY
PIN 6
SYNC IN
PIN 2
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.
www.synqor.com
Doc.# 005-0005142 Rev. 2
04/30/09
Page 10
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
Technical Specification
trim Resistance (ohms)
100,000
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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.
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 14ms as the output
voltage falls.
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:
Rtrim =
407.5
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.
1
2
3
28 Vdc
4
+
–
5
open
means
on
6
10,000
1,000
100
0.00
0.05
0.10
0.15
0.20
0.25
0.30
Increase in vout (v)
Figure E: Output Voltage Trim Graph
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 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. Factory trimmed converters are available by request.
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. 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 unless
it has remained in that state for more than about 200µs. 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.
+VIN
ENA 2
IN RTN
SHARE
CASE
+ SNS
ENA 1
– SNS
SYNC OUT
SYNC IN
OUT RTN
+VOUT
12
11
10
9
Rtrim
–
8
7
Load
+
Figure D: Typical connection for output voltage trimming.
Product # MQFL-28E-2R5S
Phone 1-888-567-9596
www.synqor.com
Doc.# 005-0005142 Rev. 2
04/30/09
Page 11
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
Technical Specification
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, a maximum
temperature of 145ºC is permissible, but not 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.
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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 backdrive 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.
THERMAL CONSIDERATIONS: Figure 5 shows the suggested
Power Derating Curves for this converter as a function of the
case temperature, input voltage and the maximum desired power
MOSFET junction temperature. All other components within the
converter are cooler than the hottest MOSFET.
.
Product # MQFL-28E-2R5S
Phone 1-888-567-9596
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.
www.synqor.com
Doc.# 005-0005142 Rev. 2
04/30/09
Page 12
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
Technical Specification
CONSTRUCTION AND ENVIRONMENTAL STRESS SCREENING OPTIONS
Consistent with
MIL-StD-883F
C-Grade
(-40 ºC to +100 ºC)
ES-Grade
(-55 ºC to +125 ºC)
(Element Evaluation)
HB-Grade
(-55 ºC to +125 ºC)
(Element Evaluation)
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Screening
Internal visual
*
Yes
Yes
Yes
temperature Cycle
Method 1010
no
Condition B
(-55 ºC to +125 ºC)
Condition C
(-65 ºC to +150 ºC)
Constant
Acceleration
Method 2001
(Y1 Direction)
no
500g
Condition A
(5000g)
Burn-in
Method 1015
Load Cycled
• 10s period
• 2s @ 100% Load
• 8s @ 0% Load
24 Hrs @ +125 ºC
96 Hrs @ +125 ºC
160 Hrs @ +125 ºC
Final Electrical test
Method 5005
(Group A)
+25 ºC
-45, +25, +100 ºC
-55, +25, +125 ºC
Full QorSeal
Full QorSeal
Full QorSeal
*
Yes
Yes
QorSeal
QorSeal
QorSeal
Mechanical Seal,
thermal, and Coating
Process
External visual
2009
Construction Process
* Per IPC-A-610 (Rev. D) Class 3
MilQor converters and filters are offered in four variations of construction technique and environmental stress screening options. The
three highest grades, C, ES, and HB, all 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 pre-qualifies each new batch of devices.
Product # MQFL-28E-2R5S
Phone 1-888-567-9596
www.synqor.com
Doc.# 005-0005142 Rev. 2
04/30/09
Page 13
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
Technical Specification
0.093
[2.36]
+VIN
ENA 2
12
11
10
9
8
7
0.250 [6.35]
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1
2
3
4
5
6
IN RTN
CASE
ENA 1
SYNC OUT
SYNC IN
SHARE
+SNS
MQFL-28E-2R5S-X-HB
DC/DC CONVERTER
28Vin 2.5Vout @ 40A
-SNS
MADE IN USA
S/N 0000000 D/C 3205-301 CAGE 1WX10
OUT RTN
+VOUT
1.50 [38.10]
1.260
[32.00]
0.200 [5.08]
TYP. NON-CUM.
0.040 [1.02]
PIN
2.50 [63.50]
2.76 [70.10]
3.00 [76.20]
0.050 [1.27]
0.128 [3.25]
0.220 [5.59]
2.96 [75.2]
0.228 [5.79]
0.390 [9.91]
Case X
0.093
[2.36]
1
2
3
4
5
6
+VIN
ENA 2
IN RTN
CASE
ENA 1
SHARE
MQFL-28E-2R5S-U-HB
SYNC OUT
SYNC IN
+SNS
DC/DC CONVERTER
28Vin 2.5Vout @ 40A
-SNS
MADE IN USA
S/N 0000000 D/C 3205-301 CAGE 1WX10
OUT RTN
+VOUT
2.50 [63.50]
2.76 [70.10]
3.00 [76.20]
12
11
10
9
8
7
0.250 [6.35]
0.200 [5.08]
TYP. NON-CUM.
1.50 [38.10]
1.260
[32.00]
0.040 [1.02]
PIN
0.42
[10.7]
0.128 [3.25]
0.050 [1.27]
0.220 [5.59]
2.80 [71.1]
Case U
0.390 [9.91]
NOTES
PIN DESIGNATIONS
1)
Pins 0.040” (1.02mm) diameter
2)
Pins Material: Copper
Finish: Gold over Nickel plate
1
Positive input
7
Positive output
3)
All dimensions in inches (mm) Tolerances: x.xx +/-0.02 in. (x.x +/-0.5mm)
x.xxx +/-0.010 in. (x.xx +/-0.25mm)
2
Input return
8
Output return
Weight: 2.8 oz (78.5 g) typical
3
CASE
9
- Sense
4)
5)
Workmanship: Meets or exceeds IPC-A-610C Class III
4
Enable 1
10 + Sense
6)
Print Labeling on Top Surface per Product Label Format Drawing
5
Sync output
11 Share
6
Sync input
12 Enable 2
Product # MQFL-28E-2R5S
Phone 1-888-567-9596
Pin Function
www.synqor.com
Doc.# 005-0005142 Rev. 2
Pin Function
04/30/09
Page 14
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
Technical Specification
+VIN
ENA 2
0.250 [6.35]
12
2.00
11
[50.80]
10
1.50
9 [38.10]
8
1.750
7
[44.45]
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1
2
3
4
5
6
0.300 [7.62]
0.140 [3.56]
1.15 [29.21]
0.250 [6.35]
TYP
IN RTN
SHARE
CASE
ENA 1
+SNS
MQFL-28E-2R5S-Y-HB
DC/DC CONVERTER
28Vin 2.5Vout @ 40A
-SNS
SYNC OUT
SYNC IN
MADE IN USA
S/N 0000000 D/C 3205-301 CAGE 1WX10
OUT RTN
+VOUT
1.750 [44.45]
0.200 [5.08]
TYP.
NON-CUM.
0.040
[1.02]
PIN
0.050 [1.27]
0.375 [9.52]
2.50 [63.50]
0.220 [5.59]
2.96 [75.2]
0.228 [5.79]
Case Y
0.390 [9.91]
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
0.220 [5.59]
0.050 [1.27]
0.420 [10.7]
0.050 [1.27]
0.220 [5.59]
0.36 [9.2]
2.80 [71.1]
0.525 [13.33]
0.390
[9.91]
0.390
[9.91]
0.525 [13.33]
2.80 [71.1]
PIN DESIGNATIONS
NOTES
1)
2)
3)
4)
5)
6)
Pins 0.040” (1.02mm) diameter
Pins Material: Copper
Finish: Gold over Nickel plate
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-610C Class III
Print Labeling on Top Surface per Product Label Format Drawing
Product # MQFL-28E-2R5S
Phone 1-888-567-9596
www.synqor.com
Pin Function
1
2
3
4
5
6
Positive input
Input return
CASE
Enable 1
Sync output
Sync input
Doc.# 005-0005142 Rev. 2
Pin Function
7
8
9
10
11
12
Positive output
Output return
- Sense
+ Sense
Share
Enable 2
04/30/09
Page 15
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
Technical Specification
MilQor Converter FAMILY MATRIX
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The tables below show the array of MQFL 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.
Dual Output †
Single Output
Full Size
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
20A
Total
8A
Total
6.5A
Total
40A
40A
40A
30A
20A
17A
13A
11A
8A
6.5A
3.3A
20A
Total
8A
Total
6.5A
Total
40A
40A
40A
30A
24A
20A
16A
13A
10A
8A
4A
24A
Total
10A
Total
8A
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
MQFL-28
16-40Vin Cont.
16-50Vin 1s Trans.*
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 0.1s Trans.*
Absolute Max Vin = 550V
Dual Output †
Single Output
Half Size
MQHL-28 (50W)
16-40Vin Cont.
16-50Vin 1s Trans.*
Absolute Max Vin = 60V
MQHL-28E (50W)
16-70Vin Cont.
16-80Vin 1s Trans.*
Absolute Max Vin =100V
MQHR-28 (25W)
16-40Vin Cont.
16-50Vin 1s Trans.*
Absolute Max Vin = 60V
MQHR-28E (25W)
16-70Vin Cont.
16-80Vin 1s Trans.*
Absolute Max Vin =100V
Check with factory for availability.
Product # MQFL-28E-2R5S
Phone 1-888-567-9596
www.synqor.com
Doc.# 005-0005142 Rev. 2
04/30/09
Page 16
MQFL-28E-2R5S
Output: 2.5V
Current: 40A
Technical Specification
PART NUMBERING SYSTEM
The part numbering system for SynQor’s MilQor DC-DC converters follows the format shown in the table below.
Output voltage(s)
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Model
name
MQFL
MQHL
MQHR
Input
voltage
Range
28
28E
28v
28vE
270
Single
Output
Dual
Output
1R5S
1R8S
2R5S
3R3S
05S
06S
7R5S
09S
12S
15S
28S
05D
12D
15D
Example:
Package Outline/
Pin Configuration
U
X
Y
W
Z
Screening
Grade
C
ES
HB
MQFL-28E-2R5S–Y–ES
APPLICATION NOTES
A variety of application notes and technical white papers can be downloaded in pdf format from the SynQor website.
PATENTS
SynQor holds the following patents, one or more of which might apply to this product:
5,999,417
6,927,987
6,222,742
7,050,309
6,545,890
7,072,190
6,577,109
7,085,146
6,594,159
7,119,524
6,731,520
7,269,034
6,894,468
7,272,021
6,896,526
7,272,023
Contact SynQor for further information:
Phone:
Toll Free:
Fax:
E-mail:
Web:
Address:
Product # MQFL-28E-2R5S
978-849-0600
888-567-9596
978-849-0602
[email protected]
www.synqor.com
155 Swanson Road
Boxborough, MA 01719
USA
Phone 1-888-567-9596
Warranty
SynQor offers a two (2) year limited warranty. Complete warranty
information is listed on our website or is available upon request from
SynQor.
Information furnished by SynQor is believed to be accurate and reliable.
However, no responsibility is assumed by SynQor for its use, nor for any
infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any
patent or patent rights of SynQor.
www.synqor.com
Doc.# 005-0005142 Rev. 2
04/30/09
Page 17