15A/27W

Technical Specification
Quarter
Brick
48Vin 1.8Vout 15A
15 Amp, No Heatsink, Isolated DC/DC Converter
The PQ60018QML15 PowerQor™ Mega quarterbrick converter is a next-generation, board-mountable,
isolated, fixed switching frequency DC/DC converter
that uses synchronous rectification to achieve very 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 high-yield surface
mount technology, yielding an extremely reliable product that is less than 8.5mm in height. The Mega series
offer significant useable output current in an economical standard “quarter-brick” module.
Operational Features
• High efficiency, 80% at full rated load current
• Delivers up to 15 amps of output current with minimal derating - no heatsink required
• Wide input voltage range: 35V – 75V, with 100V
100ms input voltage transient protection
• Fixed frequency switching provides predictable EMI
performance
• No minimum load requirement means no preload
resistors required
Mechanical Features
• Industry standard quarter-brick pin-out configuration
• Industry standard size: 1.45” x 2.3”
• Total height only 8.5mm (0.335”), permits better airflow and smaller card pitch, meets NTT reqs.
• Total weight: 34 grams (1.2 oz.), lower mass greatly reduces vibration and shock problems
Control Features
• On/Off control referenced to input side (positive
and negative logic options are available)
• Remote sense for the output voltage compensates
for output distribution drops
• Output voltage trim permits custom voltages and
voltage margining
Product # PQ60018QML15
Phone 1-888-567-9596
PQ60018QML15 Module
Protection Features
• Input under-voltage lockout disables converter at
low input voltage conditions
• Output current limit and short circuit protection
protects converter from excessive load current or
short circuits
• Output over-voltage protection protects load from
damaging voltages
• Thermal shutdown protects converter from abnormal environmental conditions
Safety Features
• 2000V, 10 MΩ input-to-output isolation provides
input/output ground separation
• UL/cUL 60950 recognized (US & Canada), basic
insulation rating
• TUV certified to EN60950
• Meets 72/23/EEC and 93/68/EEC directives
which facilitates CE Marking in user’s end product
• Board and plastic components meet UL94V-0 flammability requirements
Doc.# 005-2QM618E Rev. A
8/16/02
Page 1
Technical Specification
Quarter
48Vin 1.8Vout 15A
Brick
MECHANICAL
DIAGRAM
2.30
(58.4)
0.300
(7.62)
2.00
(50.8)
0.450
0.150
(11.43)
(3.81)
0.14
(3.6)
0.600
(15.24)
0.300
(7.62)
0.43
(10.8)
Top View
1.45
(36.8)
0.600
(15.24)
Pin Farside
Typical
Bottom side
Clearance
Side View
See Note 9
0.019+/-0.013
(0.48+/-0.33)
Lowest
Component
0.32 (0.33 max)
(8.1, 8.5 max)
Load Board
0.145
(3.68)
See Note 3
NOTES
PIN CONNECTIONS
1) Pins 1-3, 5-7 are 0.040” (1.02mm) diameter with
0.080” (2.03 mm) diameter standoff shoulders.
2) Pins 4 and 8 are 0.062” (1.57 mm) diameter with
0.100” (2.54 mm) diameter standoff shoulders.
3) Other pin extension lengths available. Recommended pin
length is 0.03” (0.76mm) greater than the PCB thickness.
4) All Pins: Material - Copper Alloy
Finish - Tin/Lead 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: 1.2 oz. (34 g) typical
8) Workmanship: Meets or exceeds IPC-A-610C Class II
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.
Product # PQ60018QML15
Phone 1-888-567-9596
Pin No.
Name
Function
1
Vin(+)
Positive input voltage
2
ON/OFF
TTL input to turn converter
on and off, referenced to
Vin(-), with internal pull up.
3
Vin(-)
Negative input voltage
4
Vout(-)
Negative output voltage
5
SENSE(-)
Negative remote sense1
6
TRIM
Output voltage trim2
7
SENSE(+)
Positive remote sense3
8
Vout(+)
Positive output voltage
Notes:
1. Pin 5 must be connected to Vout(-).
2. Leave Pin 6 open for nominal output voltage.
3. Pin 7 must be connected to Vout(+).
Doc.# 005-2QM618E Rev. A
8/16/02
Page 2
Technical Specification
Quarter
48Vin 1.8Vout 15A
Brick
PQ60018QML15 ELECTRICAL CHARACTERISTICS
TA=25°C, airflow rate=300 LFM, Vin=48Vdc unless otherwise noted; full operating temperature range is -40°C to +100°C ambient
temperature with appropriate power derating. Specifications subject to change without notice.
Parameter
Min.
Typ.
Max.
Units
100
80
100
2000
100
125
18
V
V
V
V
°C
°C
V
Notes & Conditions
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
-40
-55
-2
INPUT CHARACTERISTICS
Operating Input Voltage Range
Input Under-Voltage Lockout
Turn-On Voltage Threshold
Turn-Off Voltage Threshold
Lockout Hysteresis Voltage
Maximum Input Current
No-Load Input Current
Disabled Input Current
Inrush Current Transient Rating
Response to Input Transient
Input Reflected-Ripple Current
Recommended Input Fuse
Input Filter Component Values (C\L)
Recommended External Input Capacitance
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
35
48
75
V
32
28.5
2.5
33
29.5
3.5
34
30.5
4.5
1.2
60
4
V
V
V
A
mA
mA
A 2s
mV
mA
A
µF\µH
µF
30
1.9
0.01
150
5
33
1.782
1.75
0
16
0.5
0
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
Output Voltage Overshoot
180
EFFICIENCY
100% Load
50% Load
1.64\4.7
47
1.800
1.818
V
+0.1 \ 2
+0.1 \ 2
+9
+0.15 \ 5
+0.15 \ 5
+27
1.85
%\mV
%\mV
mV
V
50
10
100
20
15
20
mV
mV
A
A
V
A
mA
µF
18
0.72
1.0
10
2.0
50
30,000
over sample, line, load, temperature & life
20MHz bandwidth; Fig. 13 & 16
Full Load, see Figures 13 & 16
Full Load, see Figures 13 & 16
Output Voltage 10% Low; Fig. 17
Max negative current drawn from output
Max negative current drawn from output
1.8Vout at 15A Resistive Load
80
160
400
mV
mV
µs
50% to 75% to 50% Iout max; Figure 11
50% to 75% to 50% Iout max; Figure 12
to within 1% Vout nom
ms
ms
%
Full load, Vout=90% nom.; Figs. 9 & 10
-40°C to +125°C; Figure F
10,000 µF load capacitance, Iout = 0A
%
%
Figures 1 - 4
Figures 1 - 4
°C
°C
°C
Package rated to 150°C
UL rated max operating temp 130°C
See Figures 5 - 8 for derating curves
4
200
0
8
215
125
125
125
2000
10
470
Phone 1-888-567-9596
internal values, see Figure E
see Figure 13
120 Hz; Fig. 20
Semiconductor Junction Temperature
Board Temperature
Transformer Temperature
Isolation Voltage
Isolation Resistance
Isolation Capacitance
1000V/ms input transient
P-P thru 10µH inductor; Figs. 13 & 15
fast blow external fuse recommended
dB
80
82
ISOLATION CHARACTERISTICS
100% Load, 35 Vin
80
TEMPERATURE LIMITS FOR POWER DERATING CURVES
Product # PQ60018QML15
20
continuous
continuous
100ms transient
Basic level, Pollution Degree 2
V
MΩ
pF
Doc.# 005-2QM618E Rev. A
8/16/02
Page 3
Technical Specification
Quarter
48Vin 1.8Vout 15A
Brick
ELECTRICAL CHARACTERISTICS (Continued)
Parameter P
FEATURE CHARACTERISTICS
Switching Frequency
ON/OFF Control (Option P)
Off-State Voltage
On-State Voltage
ON/OFF Control (Option N)
Off-State Voltage
On-State Voltage
ON/OFF Control (Either Option)
Pull-Up Voltage
Pull-Up Resistance
Output Voltage Trim Range
Output Voltage Remote Sense Range
Output Over-Voltage Protection
Over-Temperature Shutdown
Over-Temperature Shutdown Restart Hysteresis
Min.
Typ.
Max.
Units
230
260
290
kHz
-2
2.4
0.8
18
V
V
2.4
-2
18
0.8
V
V
9.2
V
kΩ
%
%
%
°C
°C
-20
Vin/6.5
40
117
RELIABILITY CHARACTERISTICS
Calculated MTBF
Calculated MTBF
Demonstrated MTBF
+10
+10
127
122
125
10
Notes & Conditions
Figures A, B
Measured across Pins 8 & 4; Figure C
Measured across Pins 8 & 4
Over full temp range; % of nominal Vout
Average PCB Temperature
106 Hrs. Telcordia TR-NWT-000332; 80% load,300LFM, 40oC Ta
106 Hrs. MIL-HDBK-217F; 80% load, 300LFM, 40oC Ta
106 Hrs. Field demonstrated MTBF
2.1
1.75
TBD
STANDARDS COMPLIANCE
Parameter P
Notes
STANDARDS COMPLIANCE
UL/cUL 60950
EN60950
72/23/EEC
93/68/EEC
Needle Flame Test (IEC 695-2-2)
IEC 61000-4-2
GR-1089-CORE
Telcordia (Bellcore) GR-513
File # E194341, Basic insulation & pollution degree 2
Certified by TUV
test on entire assembly; board & plastic components UL94V-0 compliant
ESD test, 8kV - NP, 15kV air - NP
Section 7 - electrical safety, Section 9 - bonding/grounding
• An external input fuse must always be used to meet these safety requirements
QUALIFICATION TESTING
Parameter P
QUALIFICATION TESTING
Life Test
Vibration
Mechanical Shock
Temperature Cycling
Power/Thermal Cycling
Design Marginality
Humidity
Solderability
# Units
32
5
5
10
5
5
5
15 pins
Test Conditions
95% rated Vin and load, units at derating point, 1000 hours
10-55Hz sweep, 0.060” total excursion,1 min./sweep, 120 sweeps for 3 axis
100g minimum, 2 drops in x and y axis, 1 drop in 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, 2 minutes on and 6 hours off
MIL-STD-883, method 2003
• Extensive characterization testing of all SynQor products and manufacturing processes is performed to ensure that we supply
robust, reliable product. Contact factory for more information about Proof of Design and Proof of Manufacturing processes.
OPTIONS
PATENTS
SynQor provides various options for Logic Sense, Pin Length and
Feature Set for this family of DC/DC converters. Please consult the
last page of this specification sheet for information on available
options.
SynQor is protected under various patents, including but not limited to U.S. Patent # 5,999,417.
Product # PQ60018QML15
Phone 1-888-567-9596
Doc.# 005-2QM618E Rev. A
8/16/02
Page 4
Performance Curves
Quarter
48Vin 1.8Vout 15A
Brick
90
84
83
85
Efficiency (%)
Efficiency (%)
82
80
75
70
35 Vin
48 Vin
75 Vin
65
2
3
5
6
8
9
11
12
14
80
79
78
25 C
77
40 C
55 C
76
60
0
81
0
15
100
Figure 1: Efficiency at nominal output voltage vs. load current for minimum, nominal, and maximum input voltage at 25°C.
300
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).
6.0
8
7
5.0
Power Dissipation (W)
Power Dissipation (W)
200
Air Flow (LFM)
Load Current (A)
6
5
4
3
2
35 Vin
1
48 Vin
4.0
3.0
2.0
25 C
40 C
1.0
55 C
75 Vin
0
0
2
3
5
6
8
9
11
12
14
15
Load Current (A)
0.0
0
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).
16
14
12
Iout (A)
10
8
6
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
4
200 LFM (1.0 m/s)
2
100 LFM (0.5 m/s)
0 LFM (0 m/s)
0
0
25
40
55
70
85
Ambient Air Temperature (oC)
Figure 5: Maximum output power derating curves vs. ambient air temperature for airflow rates of 0 LFM through 400 LFM with air flowing
across the converter from output to input (nominal input voltage).
Product # PQ60018QML15
Phone 1-888-567-9596
Semiconductor junction temperature is
within 1°C of surface temperature
Figure 6: Thermal plot of converter at 15 amp load current with 55°C
air flowing at the rate of 200 LFM. Air is flowing across the converter
sideways from output to input (nominal input voltage).
Doc.# 005-2QM618E Rev. A
8/16/02
Page 5
Performance Curves
Quarter
Brick
48Vin 1.8Vout 15A
16
14
12
Iout (A)
10
8
6
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
4
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
2
0 LFM (0 m/s)
0
0
25
40
55
70
85
Semiconductor junction temperature is
within 1°C of surface temperature
Ambient Air Temperature (oC)
Figure 7: Maximum output power derating curves vs. ambient air temperature for airflow rates of 0 LFM through 400 LFM with air flowing
from pin 3 to pin 1 (nominal input voltage).
Figure 8: Thermal plot of converter at 15 amp 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 (resistive load) (2.5 ms/div)
Ch1: Vout (1V/div)
Ch2: ON/OFF input (5V/div)
Figure 10: Turn-on transient at zero load (2.5 ms/div).
Ch1: Vout (1V/div)
Ch2: 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: 15µF, 450 mΩ ESR tantalum capacitor
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
capacitor and 1µF ceramic cap. Ch1: Vout (200mV/div), Ch2: Iout (5A/div).
and 1µF ceramic capacitor. Ch1: Vout (100mV/div), Ch2: Iout (5A/div).
Product # PQ60018QML15
Phone 1-888-567-9596
Doc.# 005-2QM618E Rev. A
8/16/02
Page 6
Performance Curves
Quarter
Brick
Figure 15
10 µH
Figure 14
source
impedance
Figure 16
iS
VSOURCE
48Vin 1.8Vout 15A
iC
DC/DC
Converter
VOUT
1 µF
47 µF,
<1Ω ESR
15 µF,
ceramic 100mΩ ESR
capacitor
tantalum
capacitor
electrolytic
capacitor
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 (100 mA/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 (5 mA/div).
See Figure 13.
Figure 16: Output voltage ripple at nominal input voltage and rated
load current (20 mV/div). Load capacitance: 1µF ceramic capacitor
and 15µF tantalum capacitor. Bandwidth: 20 MHz. See Figure 13.
Output Voltage (V)
3.0
2.0
1.0
35 V
48 V
75 V
0.0
0
5
10
15
20
Load Current (A)
Figure 17: Output voltage vs. load current showing typical current limit
curves and converter shutdown points.
Product # PQ60018QML15
Phone 1-888-567-9596
Figure 18: Load current (5A/div) as a function of time when the converter attempts to turn on into a 1 mΩ short circuit. Top trace
(2ms/div) is an expansion of the on-time portion of the bottom trace.
Doc.# 005-2QM618E Rev. A
8/16/02
Page 7
Performance Curves
Quarter
48Vin 1.8Vout 15A
Brick
0.1
0
-10
0.01
35 Vin
48 Vin
75 Vin
0.001
Forward Transmission (dB)
Output Impedance (Ω )
-20
-30
-40
35 Vin
-50
48 Vin
-60
75 Vin
-70
-80
-90
-100
0.0001
-110
10
100
1,000
10,000
100,000
10
100
Hz
1,000
10,000
100,000
Hz
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.
1000
0
100
-20
35 Vin
48 Vin
75 Vin
-30
-40
Input Impedance (Ω )
Reverse Transmission (dB)
-10
35 Vin
48 Vin
75 Vin
10
1
-50
-60
10
100
1,000
10,000
100,000
0.1
10
Hz
1,000
10,000
100,000
Hz
Figure 21: Magnitude of incremental reverse transmission (RT =
iin/iout) for minimum, nominal, and maximum input voltage at full rated
power.
Product # PQ60018QML15
100
Phone 1-888-567-9596
Figure 22: Magnitude of incremental input impedance (Zin = vin/iin)
for minimum, nominal, and maximum input voltage at full rated
power.
Doc.# 005-2QM618E Rev. A
8/16/02
Page 8
Technical Specification
Quarter
Brick
48Vin 1.8Vout 15A
BASIC OPERATION AND FEATURES
CONTROL FEATURES
The PowerQor series converter uses a two-stage power circuit
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 onstate 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 and quarter-brick converters
uses the industry standard footprint and pin-out configuration.
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 5 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(-)] – [SENSE(+) - SENSE(-)] <
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 lower than its
specified value.
ON/OFF
ON/OFF
ON/OFF
Vin(_)
Vin(_)
Vin(_)
Remote Enable Circuit
Negative Logic
(Permanently Enabled)
ON/OFF
Positive Logic
(Permanently Enabled)
5V
Vin(+)
5V
274k
ON/OFF
50k
TTL
TTL/
CMOS
ON/OFF
Vin(_)
Vin(_)
Open Collector Enable Circuit
Vin(_)
Direct Logic Drive
Figure A: Various circuits for driving the ON/OFF pin.
Product # PQ60018QML15
100pF
50k
Phone 1-888-567-9596
Figure B: Internal ON/OFF pin circuitry
Doc.# 005-2QM618E Rev. A
8/16/02
Page 9
Technical Specification
Quarter
Brick
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.
OUTPUT VOLTAGE TRIM (Pin 6): The 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 5 (SENSE(-) input). For a desired
decrease of the nominal output voltage, the value of the resistor should be
Rtrim-down =
- 10.22
(511
∆%)
(kΩ)
where
∆% =
– Vdesired
(Vnominal
) x 100%
Vnominal
To increase the output voltage, the user should connect a resistor between Pin 6 and Pin 7 (SENSE(+) input). For a desired
increase of the nominal output voltage, the value of the resistor
should be
Rtrim-up =
(
5.11VOUT(100+∆%) _ 511 _
1.225∆%
∆%
10.22
)
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 over-voltage 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.
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.
PROTECTION FEATURES
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 Turn-On 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 CurrentLimit Shutdown Voltage, the converter turns off.
(kΩ)
where
VOUT = Nominal Output Voltage
Figure C graphs the relationship between the trim resistor value
and Rtrim-up and Rtrim-down, showing the total range the output voltage can be trimmed up or down.
10,000
Trim Resistance (kOhms)
48Vin 1.8Vout 15A
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.
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.
1,000
100
10
0
2
4
6
8
10
% increase Vout
12
14
16
18
% decrease Vout
Figure C: Trim Graph for 1.8Vout module
Product # PQ60018QML15
Phone 1-888-567-9596
20
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
Doc.# 005-2QM618E Rev. A
8/16/02
Page 10
Technical Specification
Quarter
48Vin 1.8Vout 15A
Brick
More detailed information is available in the application note
titled “EMI Characteristics” on the SynQor website.
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.
APPLICATION CONSIDERATIONS
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.
Input Filtering and External 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 Characterisitcs” section.
Electrolytic
Capacitor
33µF
ESR ≅1Ω
External
Input
Filter
Vin
Vin(+)
Vout(+)
Vsense(+)
ON/OFF
Trim
Vsense(_)
Vin(_)
Rtrim-up
or
Cload
Rtrim-down
Iload
Vout(_)
Figure D: Typical application circuit (negative logic unit, permanently enabled).
L
Vin(+)
C
Vin(_)
Figure E: Internal Input Filter Diagram (component values listed on page 3).
Product # PQ60018QML15
Phone 1-888-567-9596
Doc.# 005-2QM618E Rev. A
8/16/02
Page 11
Technical Specification
Quarter
48Vin 1.8Vout 15A
Brick
Startup Inhibit Period: The Startup Inhibit Period ensures
that the converter will remain off for at least 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.
• Input Under-Voltage Lockout
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.
• Input Over-Voltage Shutdown (not present in Quarter-brick)
• Output Over-Voltage Protection
• Over Temperature Shutdown
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.
• 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
4ms (typical
Vout
turn on time)
200ms
(typical start-up
inhibit period)
t0
200ms
200ms
t1
t
t2
Figure F: Startup Inhibit Period (turn-on time not to scale)
Product # PQ60018QML15
Phone 1-888-567-9596
Doc.# 005-2QM618E Rev. A
8/16/02
Page 12
Technical Specification
Quarter
Brick
48Vin 1.8Vout 15A
PART NUMBERING SYSTEM
ORDERING INFORMATION
The part numbering system for SynQor’s PowerQor 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 3 characters
for options.
PQ 48 033 H T A 50 N K S
Options (see
Ordering Information)
Output Current
Thermal Design
Performance Level
Package Size
Output Voltage
Input Voltage
Product Family
Model Number
Input Voltage
PQ60012QML15xyz
PQ60015QML15xyz
PQ60018QML15xyz
PQ60025QML15xyz
PQ60033QML15xyz
PQ60050QML15xyz
35 - 75 V
35 - 75 V
35 - 75 V
35 - 75 V
35 - 75 V
35 - 75 V
Output Max Output
Voltage Current
1.2 V
15 A
1.5 V
15 A
1.8 V
15 A
2.5 V
15 A
3.3 V
15 A
5.0 V
15 A
The following option choices must be included in place of
the x y z spaces in the model numbers listed above.
The first 12 characters comprise the base part number and
the last 3 characters indicate available options. Although
there are no default values for enable logic and pin length,
the most common options are negative logic and 0.145”
pins. These part numbers are more likely to be readily available in stock for evaluation and prototype quantities.
Options Description: x y z
Enable
Logic
Pin
Length
Feature
Set
K - 0.110"
P - Positive N - 0.145"
S - Standard
N - Negative R - 0.180"
Y - 0.250"
Application Notes
A variety of application notes and technical white papers
can be downloaded in pdf format at www.synqor.com.
Contact SynQor for further information:
Phone:
Toll Free:
Fax:
E-mail:
Web:
Address:
Product # PQ60018QML15
508-485-8434
888-567-9596
508-485-8414
[email protected]
www.synqor.com
188 Central Street
Hudson, MA 01749
Phone 1-888-567-9596
Warranty
SynQor offers a three (3) year limited warranty. Complete warranty
information is listed on our web site 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.
Doc.# 005-2QM618E Rev. A
8/16/02
Page 13
Similar pages