25A/62.5W

Technical
Specification
PQ60025EGL25
35-75V
100V
2.5V
25A
2000V dc
Eighth-brick
Input
Transient Input
Output
Current
Isolation
DC-DC Converter
The PQ60025EGL25 PowerQor Giga eighth-brick
converter is a next-generation, board-mountable,
isolated, fixed switching frequency DC/DC converter
that uses synchronous rectification to achieve extremely
high conversion efficiency. The power dissipated by
the converter is so low that a heatsink is not required,
which saves cost, weight, height, and application
effort. All of the power and control components are
mounted to the multi-layer PCB substrate with highyield surface mount technology. Since the PowerQor
converter has no explicit thermal connections, it is
extremely reliable.
Protection Features
•
•
•
•
•
Input under-voltage lockout disables converter at low Vin conditions
Output current limit
Short circuit protection
Protection from permanent damage and hazardous conditions
Thermal shutdown protects converter from abnormal conditions
PQ60025EGL25 Model
Operational Features
•
•
•
•
•
•
Mechanical Features
•
•
•
•
Industry standard eighth-brick pin-out configuration
Industry standard size: 0.90” x 2.3”
Total height less than 0.335” (8.5mm)
Total weight: 0.68 oz. (19g)
High efficiency, 89% half load, 85% at full load
Delivers 25A full power with minimal derating - no heatsink required
Operating input voltage range: 35-75V
Input voltage transient capability: 100V, 100ms
Fixed frequency switching provides predictable EMI
No minimum load requirement
Control Features
• On/Off control referenced to input side
• Positive and negative logic options are available
• Remote sense for Vout compensates for output distribution drops
Contents
Safety Features
•
•
•
•
Page No.
UL 60950-1:2007
EN60950-1/A11:2009/A1:2010
CAN/CSA-C22.2 No. 60950-1:2007
IEC 61000-4-2
Product # PQ60025EGL25
Phone 1-888-567-9596
Mechanical Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Standards & Qualifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Technical Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Applications Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
www.synqor.com
Doc.# 005-2EG625B Rev. B
02/11/11
Page 1
Technical
Specification
PQ60025EGL25
Open Frame Mechanical Diagram
Top View
0.600 (15.24)
0.450 (11.43)
Side View
0.90 (22.86)
EGA
0.410 (10.41)
max height
See Note 9
0.300 (7.62)
0.150 (3.81)
.340 ±.014
(8.64 ±0.35)
0.110
(2.79)
8 7 6 5 4
2.30
(58.42)
2.00
(50.8)
See Note 3
0.14
(3.56)
1
2
EGA
Bottom side
Clearance
0.089 (2.26)
min clearance
See Note 9
3
0.150
(3.81)
0.300 (7.62)
0.600 (15.24)
PIN FAR SIDE
TYPICAL
SEE NOTES
1, 2, AND 3
NOTES
.019 ±.013
(0.48 ±0.33)
BOTTOMSIDE
CLEARANCE
PIN DESIGNATIONS
Pin
Name
1
Vin(+)
Function
1)
Pins 1-3, 5-7 are 0.040” (1.02mm) diameter with 0.080” (2.03mm)
diameter standoff shoulders.
2)
Pins 4 and 8 are 0.062” (1.57 mm) diameter with 0.100” (2.54 mm)
diameter standoff shoulders.
2
ON/OFF
3)
Other pin extension lengths available. Recommended pin length is
0.03” (0.76mm) greater than the PCB thickness.
3
Vin(–)
4)
All Pins: Material - Copper Alloy- Finish - Matte Tin over Nickel plate
5)
Undimensioned components are shown for visual reference only.
6)
All dimensions in inches (mm)
Tolerances: x.xx +/-0.02 in. (x.x +/- 0.5mm)
x.xxx +/-0.010 in. (x.xx +/-0.25mm)
7)
Weight: 0.68 oz. (19g) typical
8)
Workmanship: Meets or exceeds IPC-A-610C Class II
1) Pin 5 must be connected to Vout(-).
9)
UL/TUV standards require a clearance greater than 0.04” (1.02mm)
between input and output for Basic insulation. This issue should be
considered if any copper traces are on the top side of the user’s board.
Note that the ferrite cores are considered part of the input/primary
circuit
2) Leave Pin 6 open for nominal output voltage.
Product # PQ60025EGL25
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4
Vout(–)
5
Sense (-)
6
Trim
7
Sense (+)
8
Vout(+)
Positive input voltage
TTL input to turn converter on and off,
referenced to Vin(–), with internal pull up.
Negative input voltage
Negative output voltage
Negative remote sense (see note 1)
Output voltage trim (see note 2)
Positive remote sense (see note 3)
Positive output voltage
Notes:
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3) Pin 7 must be connected to Vout(+).
Doc.# 005-2EG625B Rev. B
02/11/11
Page 2
Input: 35-75V
Output: 2.5V
Current: 25A
Package: Eighth-brick
Technical Specification
PQ60025EGL25 Electrical Characteristics
Ta = 25 °C, airflow rate = 300 LFM, Vin = 48V dc unless otherwise noted; full operating temperature range is -40 °C to +100 °C baseplate temperature
with appropriate power derating. Specifications subject to change without notice.
Parameter
Min.
ABSOLUTE MAXIMUM RATINGS
Input Voltage
Non-Operating
Operating
Operating Transient Protection
Isolation Voltage (Input to Output)
Operating Temperature
Storage Temperature
Voltage at ON/OFF input pin
INPUT CHARACTERISTICS
Operating Input Voltage Range
Input Under-Voltage Lockout
Turn-On Voltage Threshold
Turn-Off Voltage Threshold
Lockout Voltage Hysteresis
Maximum Input Current
No-Load Input Current
Disabled Input Current
Inrush Current Transient Rating
Response to Input Transient
Input Reflected Ripple Current
Input Terminal Ripple Current
Recommended Input Fuse
Recommended External Input Capacitance
Input Filter Component Values (L\C)
OUTPUT CHARACTERISTICS
Output Voltage Set Point
Output Voltage Regulation
Over Line
Over Load
Over Temperature
Total Output Voltage Range
Output Voltage Ripple and Noise
Peak-to-Peak
RMS
Operating Output Current Range
Output DC Current-Limit Inception
Output DC Current-Limit Shutdown Voltage
Back-Drive Current Limit while Enabled
Back-Drive Current Limit while Disabled
Maximum Output Capacitance Electrolytic
EFFICIENCY
100% Load
50% Load
Product # PQ60025EGL25
Typ.
-40
-55
-2
Max.
Units Notes & Conditions
100
80
100
2000
100
125
18
V
V
V
V
°C
°C
V
35
48
52
V
31.5
29.5
2.4
33.3
31.5
2.8
34.4
32.4
3.2
2.4
V
V
V
A
mA
mA
A²s
mV
mA
mA
A
µF
µH\µF
32
2
4
0.01
150
4.2
220
20
33
47
2.2\3.3
2.475
2.50
2.525
V
±0.1 \ 2.5
±0.1 \ 2.5
±13
±0.2 \ 5
±0.2 \ 5
±38
2.57
%\mV
%\mV
Mv
V
130
30
25
30.0
mV
mV
A
A
V
A
mA
µF
2.43
70
17
0
26.0
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27.5
1.2
0.55
10
50
16,000
85
89
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%
%
Continuous
Continuous
100ms transient
Basic level, Pollution Degree 2
100% Load, 35V Vin
1000V/ms input transient
RMS thru10μH inductor
RMS
Fast acting external fuse recommended
Typical ESR 0.1-0.2Ω; Figure 13
Internal values
Over sample, line, load, temperature & life
20MHz bandwidth
Full load
Full load
Subject to thermal derating
Output Voltage 10% Low
See note 3
Negative current drawn from output
Negative current drawn from output
2.5Vout at 25A Resistive Load
Figures 1 - 2
Figures 1 - 2
Doc.# 005-2EG625B Rev. B
02/11/11
Page 3
Input: 35-75V
Output: 2.5V
Current: 25A
Package: Eighth-brick
Technical Specification
PQ60025EGL25 Electrical Characteristics (continued)
Ta = 25 °C, airflow rate = 300 LFM, Vin = 48V dc unless otherwise noted; full operating temperature range is -40 °C to +100 °C baseplate temperature
with appropriate power derating. Specifications subject to change without notice.
Parameter
Min.
Typ.
DYNAMIC CHARACTERISTICS
Input Voltage Ripple Rejection
Output Voltage during Load Current Transient
Step Change in Output Current (0.1A/µs)
Step Change in Output Current (5A/µs)
Settling time
Turn-On Transient
Turn-On Time
Start-Up Inhibit Time
200
Output Voltage Overshoot
ISOLATION CHARACTERISTICS
Isolation Voltage (dielectric strength)
Isolation Resistance
Isolation Capacitance (input to output)
TEMPERATURE LIMITS FOR POWER DERATING CURVES
Semiconductor Junction Temperature
Board Temperature
Transformer Temperature
FEATURE CHARACTERISTICS
Switching Frequency
245
ON/OFF Control (Option P)
Off-State Voltage
-2.0
On-State Voltage
2.4
ON/OFF Control (Option N)
Off-State Voltage
2.4
On-State Voltage
-2.0
ON/OFF Control (Either Option)
Pull-Up Voltage
Pull-Up Resistance
Output Voltage Trim Range
-20
Output Voltage Remote Sense Range
Output Over-Voltage Protection
120
Over-Temperature Shutdown
Over-Temperature Shutdown Restart Hysteresis
RELIABILITY CHARACTERISTICS
Calculated MTBF (Telcordia)
Calculated MTBF (MIL-217)
Field Demonstrated MTBF
Product # PQ60025EGL25
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Max.
Units Notes & Conditions
65
dB
120 Hz
120
180
200
mV
mV
µs
50% to 75% to 50% Iout max
50% to 75% to 50% Iout max
To within 1% Vout nom
29
220
ms
ms
%
Full load, Vout=90% nom; Figures 9 & 10
-40°C to +125°C
16,000 μF load capacitance, Iout = 0A
V
MΩ
pF
See Absolute Maximum Ratings
125
125
125
°C
°C
°C
Package rated to 150°C
UL rated max operating temp 130°C
285
kHz
0.8
18.0
V
18
0.8
V
15.00
V
kΩ
%
240
0
2000
30
470
260
See Note 4
Application notes; Figures A & B
Vin/6
40
125
125
10
+10
+10
123
2.5
1.1
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%
°C
°C
Measured across Pins 8 & 4; Figure C
Over Full Temperature Range; % of nominial Vout
Average PCB Temperature
106 Hrs. TR-NWT-000332; 80% load, 300LFM, 40°C Ta
106 Hrs. MIL-HDBK-217F; 80% load, 300LFM, 40°C Ta
106 Hrs. See our website for details
Doc.# 005-2EG625B Rev. B
02/11/11
Page 4
Input: 35-75V
Output: 2.5V
Current: 25A
Package: Eighth-brick
Technical Specification
Standards Compliance & Qualification Testing
Parameter
Notes & Conditions
STANDARDS COMPLIANCE
UL 60950-1:2007
Basic insulation
EN60950-1/A11:2009/A1:2010
CAN/CSA-C22.2 No. 60950-1:2007
IEC 61000-4-2
ESD test, 8 kV - NP, 15 kV air - NP (Normal Performance)
Note: An external input fuse must always be used to meet these safety requirements. Contact SynQor for official safety certificates on new
releases or download from the SynQor website.
Parameter
QUALIFICATION TESTING
Life Test
Vibration
Mechanical Shock
Temperature Cycling
Power/Thermal Cycling
Design Marginality
Humidity
Solderability
Product # PQ60025EGL25
# Units
32
5
5
10
5
5
5
15 pins
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Test Conditions
95% rated Vin and load, units at derating point, 1000 hours
10-55 Hz sweep, 0.060" total excursion, 1 min./sweep, 120 sweeps for 3 axis
100g minimum, 2 drops in x, y and z axis
-40 °C to 100 °C, unit temp. ramp 15 °C/min., 500 cycles
Toperating = min to max, Vin = min to max, full load, 100 cycles
Tmin-10 °C to Tmax+10 °C, 5 °C steps, Vin = min to max, 0-105% load
85 °C, 85% RH, 1000 hours, continuous Vin applied except 5 min/day
MIL-STD-883, method 2003
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Doc.# 005-2EG625B Rev. B
02/11/11
Page 5
Technical
Specification
PQ60025EGL25
Technical Figures
92
95
91
90
85
Efficiency (%)
Efficiency (%)
90
80
75
70
35 Vin
65
48 Vin
75 Vin
60
0
3
5
8
10
13
15
18
20
23
89
88
87
86
25 C
85
55 C
40 C
84
0
25
100
400
500
Figure 2: Efficiency at nominal output voltage and 60% rated power vs. airflow
rate for ambient air temperatures of 25°C, 40°C, and 55°C (nominal input
voltage).
8.0
12
11
10
9
8
7
6
5
4
3
2
1
0
7.0
Power Dissipation (W)
Power Dissipation (W)
300
Air Flow (LFM)
Load Current (A)
Figure 1: Efficiency at nominal output voltage vs. load current for minimum,
nominal, and maximum input voltage at 25°C.
200
35 Vin
48 Vin
3
5
8
10
13
15
18
20
23
5.0
4.0
3.0
2.0
25 C
40 C
1.0
75 Vin
0
6.0
55 C
0.0
25
0
Load Current (A)
100
200
300
400
500
Air Flow (LFM)
Figure 3: Power dissipation at nominal output voltage vs. load current for
minimum, nominal, and maximum input voltage at 25°C.
Figure 4: Power dissipation at nominal output voltage and 60% rated power
vs. airflow rate for ambient air temperatures of 25°C, 40°C, and 55°C (nominal
input voltage).
24
22
20
18
Iout (A)
16
14
12
10
400 LFM (2.0 m/s)
8
300 LFM (1.5 m/s)
6
200 LFM (1.0 m/s)
4
100 LFM (0.5 m/s)
2
50 LFM (0.25 m/s)
0
0
25
40
55
70
Semiconductor junction temperature is
within 1°C of surface temperature
85
o
Ambient Air Temperature ( C)
Figure 5: Maximum output power derating curves vs. ambient air temperature
for airflow rates of 50 LFM through 400 LFM with air flowing from input to
output (nominal input voltage).
Product # PQ60025EGL25
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Figure 6: Thermal plot of converter at 21A load current with 55°C air flowing at
the rate of 200 LFM. Air is flowing from input to output (nominal input voltage).
www.synqor.com
Doc.# 005-2EG625B Rev. B
02/11/11
Page 6
Technical
Specification
PQ60025EGL25
Technical Figures
24
22
20
18
Iout (A)
16
14
12
10
400 LFM (2.0 m/s)
8
300 LFM (1.5 m/s)
6
200 LFM (1.0 m/s)
4
100 LFM (0.5 m/s)
2
50 LFM (0.25 m/s)
0
0
25
40
55
70
85
Ambient Air Temperature (oC)
Figure 7: Maximum output power derating curves vs. ambient air temperature
for airflow rates of 50 LFM through 400 LFM with air flowing lenghtwise from
pin 3 to pin 1 (nominal input voltage).
Figure 8: Thermal plot of converter at 20A load current with 55°C air flowing
at the rate of 200 LFM. Air is flowing across the converter from pin 3 to pin 1
(nominal input voltage).
Figure 9: Turn-on transient at full load (10 ms/div).
Ch 1: Vout (1V/div)
Ch 2: ON/OFF input (5V/div)
Figure 10: Turn-on transient at zero load (10 ms/div).
Ch 1: Vout (1V/div)
Ch 2: ON/OFF input (5V/div)
Figure 11: Output voltage response to step-change in load current (50%-75%50% of Iout(max); dI/dt = 0.1A/µs). Load cap: 100µF100 mΩ ESR tantalum cap
and 1µF ceramic cap. Ch 1: Vout (100mV/div), Ch 2: Iout (10A/div).
Figure 12: Output voltage response to step-change in load current (50%-75%50% of Iout(max): dI/dt = 5A/µs). Load cap: 470µF 30 mΩ ESR tantalum cap
and 1µF ceramic cap. Ch 1: Vout (50mV/div), Ch 2: Iout (10A/div).
Product # PQ60025EGL25
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Doc.# 005-2EG625B Rev. B
02/11/11
Page 7
Technical
Specification
PQ60025EGL25
Technical Figures
Input
Reflected
Ripple
Current
10µH
source
impedance
Input
Terminal
Ripple
Current
iS
iC
Output
Voltage
Ripple
DC-DC
Converter
VOUT
VSOURCE
electrolytic
capacitor
47µF <1Ω
ceramic
capacitor
1µF
tantalum
capacitor
10µF 100mΩ ESR
Figure 13: Test set-up diagram showing measurement points for Input Terminal
Ripple Current (Figure 14), Input Reflected Ripple Current (Figure 15) and
Output Voltage Ripple (Figure 16).
Figure 14: Input Terminal Ripple Current, ic, at full rated output current and
nominal input voltage with 10µH source impedance and 47µF electrolytic
capacitor (200mA/div). (See Figure 13).
Figure 15: Input reflected ripple current, is, through a 10 µH source inductor at
nominal input voltage and rated load current (5mA/div). (See Figure 13).
Figure 16: Output voltage ripple at nominal input voltage and rated load current
(50mV/div). Load capacitance: one 1.0µF ceramic capacitor and one 100µF
electrolytic capacitor. Bandwidth: 20 MHz. (See Figure 13).
4.0
Output Voltage (V)
3.5
3.0
2.5
2.0
1.5
1.0
35 V
48 V
0.5
75 V
0.0
0
5
10
15
20
25
30
Load Current (A)
Figure 17: Load current (20A/div) as a function of time when the converter
attempts to turn on into a 10mΩ short circuit. Top trace (2.0ms/div) is an
expansion of the on-time portion of the bottom trace.
Product # PQ60025EGL25
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Figure 18: Output voltage vs. load current showing typical current limit curves
and converter shutdown points.
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Doc.# 005-2EG625B Rev. B
02/11/11
Page 8
Technical
Specification
PQ60025EGL25
Technical Figures
-30
0.1
Forward Transmission (dB)
-40
Output Impedance (ohms)
0.01
0.001
35 Vin
48 Vin
1,000
Hz
10,000
-70
-80
35 Vin
-90
75 Vin
-100
0.0001
100
-60
48 Vin
75 Vin
10
-50
-110
100,000
Figure 19: Magnitude of incremental output impedance (Zout = vout/iout) for
minimum, nominal, and maximum input voltage at full rated power.
10
100
Hz
1,000
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.
-10
100
Reverse Transmission (dB)
-15
Input Impedance (ohms)
-20
-25
-30
35 Vin
-35
1
35 Vin
48 Vin
48 Vin
75 Vin
75 Vin
-40
10
10
100
1,000
Hz
10,000
Figure 21: Magnitude of incremental reverse transmission (RT = iin/iout) for
minimum, nominal, and maximum input voltage at full rated power.
Product # PQ60025EGL25
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0.1
100,000
10
100
1,000
Hz
10,000
100,000
Figure 22: Magnitude of incremental input impedance (Zin = vin/iin) for
minimum, nominal, and maximum input voltage at full rated power.
www.synqor.com
Doc.# 005-2EG625B Rev. B
02/11/11
Page 9
Technical
Specification
PQ60025EGL25
Applications Section
BASIC OPERATION AND FEATURES
CONTROL FEATURES
The PowerQor series converter uses a two-stage power
conversion topology. The first stage is a buck-converter that
keeps the output voltage constant over variations in line,
load, and temperature. The second stage uses a transformer
to provide the functions of input/output isolation and voltage
step-down to achieve the low output voltage required.
REMOTE ON/OFF (Pin 2): The ON/OFF input, Pin 2,
permits the user to control when the converter is on or off.
This input is referenced to the return terminal of the input
bus,
Vin(-). There are two versions of the converter that
differ by the sense of the logic used for the ON/OFF input.
Both the first stage and the second stage switch at a fixed
frequency for predictable EMI performance. Rectification of
the transformer’s output is accomplished with synchronous
rectifiers. These devices, which are MOSFETs with a very low
on-state resistance, dissipate far less energy than Schottky
diodes. This is the primary reason that the PowerQor
converter has such high efficiency, even at very low output
voltages and very high output currents.
Dissipation throughout the converter is so low that it does
not require a heatsink for operation. Since a heatsink is not
required, the PowerQor converter does not need a metal
baseplate or potting material to help conduct the dissipated
energy to the heatsink. The PowerQor converter can thus
be built more simply and reliably using high yield surface
mount techniques on a PCB substrate.
The PowerQor series of half-brick, quarter-brick and eighthbrick converters uses the industry standard footprint and
pin-out configuration.
ON/OFF
ON/OFF
ON/OFF
In the positive logic version, the ON/OFF input is active high
(meaning that a high turns the converter on). In the negative
logic version, the ON/OFF signal is active low (meaning that
a low turns the converter on). Figure A details five possible
circuits for driving the ON/OFF pin. Figure B is a detailed
look of the internal ON/OFF circuitry.
REMOTE SENSE(+) (Pins 7 and 5): The SENSE(+)
inputs correct for voltage drops along the conductors that
connect the converter’s output pins to the load.
Pin 7 should be connected to Vout(+) and Pin 6 should
be connected to Vout(-) at the point on the board where
regulation is desired. A remote connection at the load can
adjust for a voltage drop only as large as that specified in
this datasheet, that is
[Vout(+) - Vout(-)] – [Vsense(+) - Vsense(-)] <
Sense Range % x Vout
Pins 7 and 5 must be connected for proper regulation of
the output voltage. If these connections are not made,
the converter will deliver an output voltage that is slightly
higher than its specified value.
Note: the output over-voltage protection circuit senses the
voltage across the output (pins 8 and 4) to determine when
it should trigger, not the voltage across the converter’s
sense leads (pins 7 and 5). Therefore, the resistive drop on
the board should be small enough so that output OVP does
not trigger, even during load transients.
5k
Vin(+)
Vin(_)
Vin(_)
Remote Enable Circuit
Negative Logic
(Permanently
Enabled)
5V
ON/OFF
Vin(_)
Positive Logic
(Permanently
Enabled)
TTL/
CMOS
Vin(_)
274k
ON/OFF
50k
TTL
100pF
ON/OFF
Vin(_)
50k
Vin(_)
Direct Logic Drive
Open Collector Enable Circuit
Figure A: Various circuits for driving the ON/OFF pin
Figure B: Internal ON/OFF pin circuitry
Product # PQ60025EGL25
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Doc.# 005-2EG625B Rev. B
02/11/11
Page 10
Technical
Specification
PQ60025EGL25
Applications Section
OUTPUT VOLTAGE TRIM (Pin 6): TThe TRIM input
permits the user to adjust the output voltage across
the sense leads up or down according to the trim range
specifications.
To decrease the output voltage, the user should connect
a resistor between Pin 6 and Pin 7 (SENSE(-) input). For a
desired decrease of the nominal output voltage, the value
of the resistor should be:
(
Rtrim-down =
) - 10.22(kΩ)
511%
Δ%
where
To decrease the output voltage, the user should connect
a resistor between Pin 6 and Pin 7 (SENSE(-) input). For a
desired decrease of the nominal output voltage, the value
of the resistor should be:
Rtrim-up =
( 5.11Vout
1.225Δ%
_ 511
Δ%
- 10.22
) kΩ
where
Trim Resistance (kOhms)
10,000
1,000
100
10
1
2
4
6
8
10
% increase Vout
12
Input Under-Voltage Lockout: The converter is designed
to turn off when the input voltage is too low, helping avoid
an input system instability problem, described in more detail
in the application note titled “Input System Instability”. The
lockout circuitry is a comparator with DC hysteresis. When
the input voltage is rising, it must exceed the typical TurnOn Voltage Threshold value (listed on the specification
page) before the converter will turn on. Once the converter
is on, the input voltage must fall below the typical Turn-Off
Voltage Threshold value before the converter will turn off.
Output Current Limit: The maximum current limit remains
constant as the output voltage drops. However, once the
impedance of the short across the output is small enough
to make the output voltage drop below the specified Output
DC Current-Limit Shutdown Voltage, the converter turns off.
The converter then enters a “hiccup mode” where it
repeatedly turns on and off at a 5 Hz (nominal) frequency
with a 5% duty cycle until the short circuit condition is
removed. This prevents excessive heating of the converter
or the load board.
Vout = Nominal Ouput Voltage
0
Protection Features
14
16
18
20
% decrease Vout
Figure C: Trim Graph 2.5V Module.
Note: The TRIM feature does not affect the voltage at
which the output over-voltage protection circuit is triggered.
Trimming the output voltage too high may cause the overvoltage protection circuit to engage, particularly during
transients.
It is not necessary for the user to add capacitance at the
Trim pin. The node is internally bypassed to eliminate noise.
Output Over-Voltage Limit: If the voltage across the
output pins exceeds the Output Over-Voltage Protection
threshold, the converter will immediately stop switching.
This prevents damage to the load circuit due to 1) excessive
series resistance in output current path from converter
output pins to sense point, 2) a release of a short-circuit
condition, or 3) a release of a current limit condition. Load
capacitance determines exactly how high the output voltage
will rise in response to these conditions. After 200 ms the
converter will automatically restart.
Over-Temperature Shutdown: A temperature sensor
on the converter senses the average temperature of the
module. The thermal shutdown circuit is designed to turn the
converter off when the temperature at the sensed location
reaches the Over-Temperature Shutdown value. It will allow
the converter to turn on again when the temperature of the
sensed location falls by the amount of the Over-Temperature
Shutdown Restart Hysteresis value.
Total DC Variation of Vout: For the converter to meet its
full specifications, the maximum variation of the DC value of
Vout, due to both trimming and remote load voltage drops,
should not be greater than that specified for the output
voltage trim range.
Product # PQ60025EGL25
Phone 1-888-567-9596
www.synqor.com
Doc.# 005-2EG625B Rev. B
02/11/11
Page 11
Technical
Specification
PQ60025EGL25
Applications Section
APPLICATION CONSIDERATIONS
Input Filtering and External Input Capacitance:
Figure E below provides a diagram showing the internal
input filter components. This filter dramatically reduces
input terminal ripple current, which otherwise could
exceed the rating of an external electrolytic input
capacitor. The recommended external input capacitance
is specified in the “Input Characteristics” section. More
detailed information is available in the application note
titled “EMI Characteristics” on the SynQor website.
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 web
site (www.synqor.com) which provides an understanding
of why this instability arises, and shows the preferred
solution for correcting it.
Application Circuits: Figure D below provides a typical
circuit diagram which details the input filtering and voltage
trimming.
Vout(+)
Vin(+)
Vin
Vsense(+)
Electrolytic
Capacitor
External
Input
Filter
47µF
Trim
ON/OFF
Vsense(_)
Vin(_)
Rtrim-up
or
Rtrim-down
Cload
Iload
Vout(_)
Figure D: Typical application circuit (negative logic unit, permanently enabled).
Lin
Vin(+)
C
Vin(_)
Figure E: Internal Input Filter Diagram (component values listed on page 3).
Product # PQ60025EGL25
Phone 1-888-567-9596
www.synqor.com
Doc.# 005-2EG625B Rev. B
02/11/11
Page 12
Technical
Specification
PQ60025EGL25
Applications Section
Startup Inhibit Period: The Startup Inhibit Period
ensures that the converter will remain off for approximately
200ms when it is shut down for any reason. When an
output short is present, this generates a 5Hz "hiccup
mode," which prevents the converter from overheating.
In all, there are seven ways that the converter can be shut
down, initiating a Startup Inhibit Period:
Before time t0, when the input voltage is below the UVL
threshold, the unit is disabled by the Input Under-Voltage
Lockout feature. When the input voltage rises above
the UVL threshold, the Input Under-Voltage Lockout is
released, and a Startup Inhibit Period is initiated. At the
end of this delay, the ON/OFF pin is evaluated, and since
it is active, the unit turns on.
•
•
•
•
•
•
•
At time t1, the unit is disabled by the ON/OFF pin, and it
cannot be enabled again until the Startup Inhibit Period
has elapsed.
When the ON/OFF pin goes high after t2, the Startup
Inhibit Period has elapsed, and the output turns on within
the typical Turn-On Time.
Input Under-Voltage Lockout.
Input Over-Voltage Shutdown (not present in Quarter-brick)
Output Over-Voltage Protection
Over Temperature Shutdown
Current Limit
Short Circuit Protection
Turned off by the ON/OFF input
Figure F shows three turn-on scenarios, where a Startup
Inhibit Period is initiated at t0, t1, and t2:
Vin
Under-Voltage
Lockout Turn-On
Threshold
ON/OFF
(pos logic)
ON
OFF
OFF ON
ON
9ms
Vout
(typical
turn on time)
200ms
200ms
200ms
(typical start-up
inhibit period)
t0
t1
t
t2
Figure F: Startup Inhibit Period (turn-on time not to scale)
Product # PQ60025EGL25
Phone 1-888-567-9596
www.synqor.com
Doc.# 005-2EG625B Rev. B
02/11/11
Page 13
Technical
Specification
PQ60025EGL25
Ordering Information
Part Numbering System
Ordering Information
The part numbering system for SynQor’s dc-dc converters follows the format
shown in the example below.
The tables below show the valid model numbers and ordering options for
converters in this product family. When ordering SynQor converters, please
ensure that you use the complete 15 character part number consisting of
the 12 character base part number and the additional characters for options.
Add “-G” to the model number for 6/6 RoHS compliance.
PQ 6 0 0 2 5 E G L 2 5 N R S - G
6/6 RoHS
Options
(see
Ordering Information)
Model Number
Input Voltage
PQ60025EGw25xyz-G
35-75V
Output
Voltage
2.5V
Max Output
Current
25A
Output Current
Thermal Design
The following options must be included in place of the w x y z spaces in the
model numbers listed above.
Performance Level
Package Size
Thermal Design
Output Voltage
A - Open Frame
L - Low Profile
Bottomside clearance:
0.019" EGL
0.089" EGA
Input Voltage
Product Family
The first 12 characters comprise the base part number and the last 3
characters indicate available options. The “-G” suffix indicates 6/6 RoHS
compliance.
Options Description: w x y z
Enable Logic
Pin Style
N - Negative
P - Positive
K - 0.110"
N - 0.145"
R - 0.180"
Y - 0.250"
Feature Set
S - Standard
Not all combinations make valid part numbers, please contact SynQor for
availability. See the Product Summary web page for more options.
Application Notes
A variety of application notes and technical white papers can be downloaded
in pdf format from our website.
RoHS Compliance: The EU led RoHS (Restriction of Hazardous
Substances) Directive bans the use of Lead, Cadmium, Hexavalent
Chromium, Mercury, Polybrominated Biphenyls (PBB), and Polybrominated
Diphenyl Ether (PBDE) in Electrical and Electronic Equipment. This SynQor
product is 6/6 RoHS compliant. For more information please refer to
SynQor’s RoHS addendum available at our RoHS Compliance / Lead Free
Initiative web page or e-mail us at [email protected]
PATENTS
SynQor holds the following U.S. patents, one or more of which apply to
each product listed in this document. Additional patent applications may
be pending or filed in the future.
Contact SynQor for further information:
Phone:
Toll Free:
Fax:
E-mail:
Web:
Address:
Product # PQ60025EGL25
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
5,999,417
6,222,742
6,545,890
6,577,109
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
Warranty
SynQor offers a three (3) 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.# 005-2EG625B Rev. B
02/11/11
Page 14
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