Product # PQ48120HGA12 Phone 1-888-567-9596 Doc.# 005-2HG412C Rev. B 9/8/04 Page 1
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Technical Specification
48Vin 12Vout 12.5A
150 Watt, No Heatsink, Isolated DC/DC Converter
Mechanical Features
• Industry standard pin-out configuration
• Industry standard size: 2.3” x 2.4” (58.4x61.0mm)
• Total height only 0.40” (10.2mm), permits better air-
flow and smaller card pitch
• Total weight: 2.1 oz. (59 grams)
Safety Features
• 2000V, 30 MΩinput-to-output isolation
• UL/cUL 60950 recognized (US & Canada), basic
insulation rating
• TUV certified to EN60950
• Meets 72/23/EEC and 93/68/EEC directives
• Meets UL94V-0 flammability requirements
Operational Features
• Ultra-high efficiency, >90% at full rated load current
• Delivers up to 150 watts of output power with mini-
mal derating - no heatsink required
• Wide input voltage range: 35V – 75V meets or
exceeds all 48V bus standards
• Fixed frequency switching provides predictable EMI
performance
Protection Features
• Input under-voltage lockout and over-voltage
shutdown protects against abnormal input voltages
• Output current limit and short circuit protection
• Output over-voltage protection
• Thermal shutdown
• Active back bias limit prevents damage to convert-
er from external load induced pre-bias
The PQ48120HGA12 PowerQor
™
Giga 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.
The Giga series converters offer enhanced useable
output current in a standard “half-brick” module.
The Giga units also feature active current sharing
for N+1 and parallel applications.
PQ48120HGA12 Module
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
Optional Features (Full-Feature modules)
• Active current share for N+1 and parallel applications
• External Clock Synchronization pin for better EMI
characteristics
• Startup Synchronization pin for more consistent start-
up sequence
• ORing FET drive supply for efficient ORing protection
Product # PQ48120HGA12 Phone 1-888-567-9596 Doc.# 005-2HG412C Rev. B 9/8/04 Page 2
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Technical Specification
48Vin 12Vout 12.5A
0.19
(4.8)
1.90
(48.3)
2.30
(58.4)
0.50
(12.7)
0.400
(10.16)
0.300 (7.62)
0.200 (5.08)
0.200 (5.08)
Load Board
Bottom side
Clearance
See Note 10
Max. Height
Lowest
Component
1.400
(35.56)
1.000
(25.40)
2.40
(61.0)
0.400
(10.16)
1.000
(25.40)
1.400
(35.56)
0.700
(17.78)
0.40
(10.2)
0.034+/-0.026
(0.86+/-0.66)
Top View
Side View
Pins in Italics Shaded text are Optional
0.145
(3.68)
See Note 4
NOTES
1) Pins 1-4, 6-8, A-C are 0.040” (1.02mm) diameter. with
0.080” (2.03mm) diameter standoff shoulders.
2) Pins 5 and 9 are 0.080” (2.03 mm) diameter with
0.125” (3.18mm) diameter standoff shoulders.
3) Pins 3, A, B & C only included in Full-Feature models.
4) Other pin extension lengths available. Recommended pin
length is 0.03” (0.76mm) greater than the PCB thickness.
5) All Pins: Material - Copper Alloy
Finish - Tin/Lead over Nickel plate
6) Undimensioned components are shown for visual
reference only.
7) All dimensions in inches (mm)
Tolerances: x.xx +/-0.02 in. (x.x +/-0.5mm)
x.xxx +/-0.010 in. (x.xx +/-0.25mm)
8) Weight: 2.1 oz. (59 g) typical
9) Workmanship: Meets or exceeds IPC-A-610C Class II
10)
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 consid-
ered part of the input/primary circuit.
MECHANICAL
DIAGRAM
PIN DESIGNATIONS
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 I share Single wire parallel signal
4 Vin(-) Negative input voltage
5 Vout(-) Negative output voltage
6 SENSE(-) Return remote sense
7 TRIM Output voltage trim
8 SENSE(+) Positive remote sense
9 Vout(+) Positive output voltage
A Clock Sync Clock synchronization
B Start Sync Startup synchronization
C OR Drive External OR-FET drive
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Technical Specification
48Vin 12Vout 12.5A
Parameter
Min. Typ. Max. Units Notes & Conditions
ABSOLUTE MAXIMUM RATINGS
Input Voltage
Non-Operating 100 V continuous
Operating 80 V continuous
Operating Transient Protection
100 V
<10
µs
Isolation Voltage (input to output) 2000 V Basic insulation level, Pollution degree 2
Operating Temperature -40 100
°C
Storage Temperature -55 125
°C
Voltage at ON/OFF input pin -2 18 V
Voltage at Clock Sync pin -15 18 V applies to Full Feature option only
INPUT CHARACTERISTICS
Operating Input Voltage Range 35 48 75 V
Input Under-Voltage Lockout
Turn-On Voltage Threshold 31.5 33.3 34.4 V
Turn-Off Voltage Threshold 29.5 31.0 32.4 V
Lockout Voltage Hysteresis 2.2 2.3 2.4 V
Input Over-Voltage Shutdown 76.7 78.3 79.5 V
Maximum Input Current 4.8 A 100% Load, 35 Vin
No-Load Input Current 75 95 mA
Disabled Input Current 2 5 mA
Inrush Current Transient Rating 0.03 A2s
Input Reflected Ripple Current 4 mA RMS thru 10
µH inductor; Figs. 13 & 15
Input Terminal Ripple Current 70 mA RMS
; Figs. 13 & 14
Recommended Input Fuse 20 A fast blow external fuse recommended
Input Filter Component Values (C1\L\C2) 1.6\4\3.3
µF\µH\µF internal values, see Figure E
Recommended External Input Capacitance 47
µF Typical ESR 0.1-0.2
Ω
, see Figure 13
OUTPUT CHARACTERISTICS
Output Voltage Set Point 11.780 12.000 12.200 V Factory pre-set with Sense(+), Sense(-) open
Output Voltage Regulation
Over Line +0.05 \ 6 +0.1 \ 12 %\mV
Over Load +0.1 \ 12 +0.2 \ 24 %\mV
Over Temperature +15 +30 mV
Total Output Voltage Range 11.714 12.266 V over sample, line, load, temperature & life
Output Voltage Ripple and Noise120MHz bandwidth; Fig. 13 & 16
Peak-to-Peak 50 100 mV Full Load, see Figures 13 & 16
RMS 10 20 mV Full Load, see Figures 13 & 16
Operating Output Current Range 0 12.5 A Subject to thermal derating; Figs. 5-8
Output DC Current-Limit Inception 15 A Output Voltage 10% Low; Fig. 17
Output DC Current-Limit Shutdown Voltage 10 V
Current Share Accuracy (2 units paralleled) +2+5 % % of rated output current
Back-Drive Current Limit while Enabled 0.45 A Negative current drawn from output
Back-Drive Current Limit while Disabled 0 10 50 mA Negative current drawn from output
Maximum Output Capacitance 12,000
µF
12Vout at 12.5A Resistive Load
DYNAMIC CHARACTERISTICS
Input Voltage Ripple Rejection 75 dB 120 Hz; Fig. 20
Output Voltage During Load Current Transient
For a Step Change in Output Current (0.1A/µs) 400 mV 50% to 75% to 50% Iout max; Figure 11
For a Step Change in Output Current (5A/µs) 300 mV 50% to 75% to 50% Iout max; Figure 12
Settling Time 300 µs to within 1% Vout nom
Turn-On Transient
Turn-On Time 20 30 ms Full load, Vout=90% nom.; Figs. 9 & 10
Start-Up Inhibit Time 180 200 240 ms
-40°C to +125°C; Figure A
Output Voltage Overshoot 0 % 10,000 µF load capacitance, Iout = 0A
EFFICIENCY
100% Load 90.7 % Figures 1 - 4
50% Load 91.7 % Figures 1 - 4
TEMPERATURE LIMITS FOR POWER DERATING CURVES
Semiconductor Junction Temperature 125 °C Package rated to 150°C
Board Temperature 125 °C UL rated max operating temp 130°C
Transformer Temperature 125 °C See Figures 5 - 8 for derating curves
ISOLATION CHARACTERISTICS
Isolation Voltage (dielectric strength) 2000 V
Isolation Resistance 30 M
Ω
Isolation Capacitance
2
3300 pF
PQ48120HGA12 ELECTRICAL CHARACTERISTICS
T
A
=25°C, airflow rate=300 LFM, V
in
=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.
Note 1: For applications requiring reduced output voltage ripple and noise, consult SynQor applications support (e-mail: support@synqor.com)
Note 2: Higher values of isolation capacitance can be added external to the module.
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Technical Specification
48Vin 12Vout 12.5A
Parameter
PMin. Typ. Max. Units Notes & Conditions
FEATURE CHARACTERISTICS
Switching Frequency 205 230 255 kHz Regulation stage and isolation stage
ON/OFF Control (Option P)
Off-State Voltage -2 0.8 V
On-State Voltage 2.7 18 V
ON/OFF Control (Option N)
Off-State Voltage 2.7 18 V
On-State Voltage -2 0.8 V
ON/OFF Control (Either Option) Figures A, B
Pull-Up Voltage Vin/6 15 V
Pull-Up Resistance 42 k
Ω
Output Voltage Trim Range -10 +7 % Measured across Pins 9 & 5; Figure C
Output Voltage Remote Sense Range +7 % Measured across Pins 9 & 5
Output Over-Voltage Protection 108 115 121 % Over full temp range; % of nominal Vout
Over-Temperature Shutdown 120 °C Average PCB Temperature
Over-Temperature Shutdown Restart Hysteresis 10 °C
Load Current Scale Factor 400 See App Note: Output Load Current Calc.
RELIABILITY CHARACTERISTICS
Calculated MTBF (Telcordia) 2.3 106Hrs. TR-NWT-000332; 80% load,300LFM, 40oC Ta
Calculated MTBF (MIL-217) 1.5 106Hrs. MIL-HDBK-217F; 80% load, 300LFM, 40oC Ta
Field Demonstrated MTBF 106Hrs. See website for latest values
STANDARDS COMPLIANCE
Parameter
PNotes
STANDARDS COMPLIANCE
UL/cUL 60950 File # E194341, Basic insulation & pollution degree 2
EN60950 Certified by TUV
72/23/EEC
93/68/EEC
Needle Flame Test (IEC 695-2-2) test on entire assembly; board & plastic components UL94V-0 compliant
IEC 61000-4-2 ESD test, 8kV - NP, 15kV air - NP (Normal Performance)
GR-1089-CORE Section 7 - electrical safety, Section 9 - bonding/grounding
•
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.
QUALIFICATION TESTING
Parameter
P# Units Test Conditions
QUALIFICATION TESTING
Life Test 32 95% rated Vin and load, units at derating point, 1000 hours
Vibration 5 10-55Hz sweep, 0.060” total excursion,1 min./sweep, 120 sweeps for 3 axis
Mechanical Shock 5 100g minimum, 2 drops in x and y axis, 1 drop in z axis
Temperature Cycling 10 -40°C to 100°C, unit temp. ramp 15°C/min., 500 cycles
Power/Thermal Cycling 5 Toperating = min to max, Vin = min to max, full load, 100 cycles
Design Marginality 5 Tmin-10°C to Tmax+10°C, 5°C steps, Vin = min to max, 0-105% load
Humidity 5 85°C, 85% RH, 1000 hours, 2 minutes on and 6 hours off
Solderability 15 pins 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 official product family qualification document.
ELECTRICAL CHARACTERISTICS (Continued)
OPTIONS
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.
PATENTS
SynQor is protected under various patents, including but not lim-
ited to U.S. Patent #s 5,999,417; 6,222,742 B1; 6,594,159
B2; 6,545,890 B2.
60
65
70
75
80
85
90
95
100
01245678101112
Load Current (A)
Efficiency (%)
36 Vin
48 Vin
75 Vin
Product # PQ48120HGA12 Phone 1-888-567-9596 Doc.# 005-2HG412C Rev. B 9/8/04 Page 5
88
89
90
91
92
93
94
0 100 200 300 400 500
Air Flow (LFM)
Efficiency (%)
25 C
40 C
55 C
0
2
4
6
8
10
12
14
16
18
01245678101112
Load Current (A)
Power Dissipation (W)
36 Vin
48 Vin
75 Vin
4.0
5.0
6.0
7.0
8.0
9.0
10.0
11.0
12.0
0 100 200 300 400 500
Air Flow (LFM)
Power Dissipation (W)
25 C
40 C
55 C
0
1
2
3
4
5
6
7
8
9
10
11
12
0 2540557085
Ambient Air Temperature (oC)
Iout (A)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
0 LFM (0 m/s)
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Performance Curves
48Vin 12Vout 12.5A
Figure 1: Efficiency at nominal output voltage vs. load current for min-
imum, nominal, and maximum input voltage at 25
°
C.
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).
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).
Figure 5: Maximum output power derating curves vs. ambient air tem-
perature for airflow rates of 0 LFM through 400 LFM with air flowing
from output to input (nominal input voltage).
Figure 6: Thermal plot of converter at 11.4 amp load current (137W)
with 55
°
C air flowing at the rate of 200 LFM. Air is flowing across the
converter from output to input (nominal input voltage).
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Performance Curves
48Vin 12Vout 12.5A
0
1
2
3
4
5
6
7
8
9
10
11
12
0 2540557085
Ambient Air Temperature (oC)
Iout (A)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
0 LFM (0 m/s)
Figure 7: Maximum output power derating curves vs. ambient air tem-
perature for airflow rates of 0 LFM through 400 LFM with air flowing
from input to output (nominal input voltage).
Figure 8: Thermal plot of converter at 10 amp load current (120W)
with 55
°
C air flowing at the rate of 200 LFM. Air is flowing across the
converter from input to output (nominal input voltage).
Figure 9: Turn-on transient at full load (resistive load) (10 ms/div).
Input voltage pre-applied. Top Trace: Vout (5V/div). Bottom Trace:
ON/OFF input (5V/div)
Figure 10: Turn-on transient at zero load (10 ms/div).
Top Trace: Vout (5V/div)
Bottom Trace: 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/
µ
s). Load cap: 15
µ
F, 450 m
Ω
ESR tantalum capacitor
and 1
µ
F ceramic capacitor. Top trace: Vout (500mV/div), Bottom trace: Iout (5A/div).
Figure 12: Output voltage response to step-change in load current (50%-75%-50%
of Iout(max): dI/dt = 5A/
µ
s). Load cap: 480
µ
F, 15 m
Ω
ESR tantalum capacitor and
1
µ
F ceramic capacitor. Top trace: Vout (500mV/div), Bottom trace: Iout (5A/div).
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Performance Curves
48Vin 12Vout 12.5A
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 cur-
rent and nominal input voltage with 10
µ
H source impedance and 47
µ
F
electrolytic capacitor (100 mA/div). (See Figure 13)
Figure 15: Input reflected ripple current, is, through a 10
µ
H 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: 1
µ
F ceramic capacitor
and 10
µ
F tantalum capacitor. Bandwidth: 20 MHz. (See Figure 13)
Figure 17: Output voltage vs. load current showing typical current limit
curves and converter shutdown points.
Figure 18: Load current (10A/div) as a function of time when the con-
verter attempts to turn on into a 1 m
Ω
short circuit. Top trace
(2.5ms/div) is an expansion of the on-time portion of the bottom trace.
10
µ
H
source
impedance
DC/DC
Converter
See Fig. 15
See Fig. 14
See Fig. 16
1
µ
F
ceramic
capacitor
15
µ
F,
450m
Ω
ESR
tantalum
capacitor
47
µ
F,
<1
Ω
ESR
electrolytic
capacitor
VSOURCE
iSiCVOUT
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Performance Curves
48Vin 12Vout 12.5A
0.0001
0.001
0.01
0.1
1
10 100 1,000 10,000 100,000
Hz
Output Impedance (
ΩΩ
)
35 Vin
48 Vin
75 Vin
Figure 19: Magnitude of incremental output impedance (Zout =
vout/iout) for minimum, nominal, and maximum input voltage at full
rated power.
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
10 100 1,000 10,000 100,000
Hz
Forward Transmission (dB)
35 Vin
48 Vin
75 Vin
Figure 20: Magnitude of incremental forward transmission (FT =
vout/vin) for minimum, nominal, and maximum input voltage at full
rated power.
-60
-50
-40
-30
-20
-10
0
10
10 100 1,000 10,000 100,000
Hz
Reverse Transmission (dB)
35 Vin
48 Vin
75 Vin
Figure 21: Magnitude of incremental reverse transmission (RT =
iin/iout) for minimum, nominal, and maximum input voltage at full rated
power.
0.1
1
10
100
10 100 1,000 10,000 100,000
Hz
Input Impedance (
ΩΩ
)
35 Vin
48 Vin
75 Vin
Figure 22: Magnitude of incremental input impedance (Zin = vin/iin)
for minimum, nominal, and maximum input
voltage at full rated power.
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Technical Specification
48Vin 12Vout 12.5A
BASIC OPERATION AND FEATURES
The
Power
Qor series converter uses a two-stage power conver-
sion topology. The first stage is a buck-converter that keeps the
output voltage constant over variations in line, load, and tem-
perature. 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.
Both the first stage and the second stage switch at a fixed fre-
quency for predictable EMI performance. Rectification of the
transformer’s output is accomplished with synchronous recti-
fiers. 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
Power
Qor 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
Power
Qor converter does not need a metal base-
plate or potting material to help conduct the dissipated energy
to the heatsink. The
Power
Qor converter can thus be built more
simply and reliably using high yield surface mount techniques
on a PCB substrate.
The
Power
Qor series of half-brick and quarter-brick converters
uses the industry standard footprint and pin-out configuration.
CONTROL FEATURES
REMOTE ON/OFF (Pin 2): The ON/OFF input, Pin 2, per-
mits 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.
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 cir-
cuits for driving the ON/OFF pin. Figure B is a detailed look of
the internal ON/OFF circuitry.
REMOTE SENSE(+) (Pins 8 and 6): The SENSE(+) inputs
correct for voltage drops along the conductors that connect the
converter’s output pins to the load.
Pin 8 should be connected to Vout(+) and Pin 6 should be con-
nected to Vout(-) at the point on the board where regulation is
desired. A remote connection at the load can adjust for a volt-
age drop only as large as that specified in this datasheet, that
is
[Vout(+) - Vout(-)]– [Vsense(+) - Vsense(-)]<
Sense Range % x Vout
Pins 8 and 6 must be connected for proper regulation of the out-
put voltage. If these connections are not made, the converter
will deliver an output voltage that is slightly lower than its spec-
ified value.
Open Collector Enable Circuit
Figure A: Various circuits for driving the ON/OFF pin. Figure B: Internal ON/OFF pin circuitry
Remote Enable Circuit
Direct Logic Drive
Negative Logic
(Permanently Enabled)
Positive Logic
(Permanently Enabled)
ON/OFF
Vin(_)
ON/OFF
ON/OFF
Vin(_)
ON/OFF
5V
TTL/
CMOS
Vin(_)
ON/OFF
Vin(_)
Vin(_)
TTL
5V
50k
274k
Vin(+)
ON/OFF
Vin(_)
50k
100pF
Note: the output over-voltage protection circuit senses the volt-
age across the output (pins 9 and 5) to determine when it
should trigger, not the voltage across the converter’s sense
leads (pins 8 and 6). 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 7): 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 resis-
tor between Pin 7 and Pin 6 (SENSE(-) input). For a desired
decrease of the nominal output voltage, the value of the resis-
tor should be
Rtrim-down =
(
100%
)
- 2 (kΩ)
∆
where
∆% =Vnominal – Vdesired x100%
Vnominal
To increase the output voltage, the user should connect a resis-
tor between Pin 7 and Pin 8 (SENSE(+) input). For a desired
increase of the nominal output voltage, the value of the resistor
should be
Figure C graphs the relationship between the trim resistor value
and Rtrim-up and Rtrim-down, showing the total range the out-
put voltage can be trimmed up or down.
Figure C: Trim Graph for 12Vout 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 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 cir-
cuitry is a comparator with DC hysteresis. When the input volt-
age 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 volt-
age must fall below the typical Turn-Off Voltage Threshold value
before the converter will turn off.
Input Over-Voltage Shutdown: Available on PQ48 mod-
els only. The converter turns off when the input voltage is too
high, allowing the converter to withstand an input voltage as
high as 100V without destruction. The shutdown circuitry is a
comparator with DC hysteresis. When the input voltage
exceeds the typical Input Over-Voltage Shutdown value, the
converter will turn off. Once the converter is off, it will turn back
on when the input voltage falls below the minimum Input Over-
Voltage Shutdown value.
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.
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 dam-
age to the load circuit due to 1) excessive series resistance in
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48Vin 12Vout 12.5A
1
10
100
1,000
10,000
012345678910
Trim Resistance (kOhms)
% Increase in Vout % Decrease in Vout
(kΩ)
Rtrim-up =
(
Vnominal – 2
)
xVDES + VNOM
1.225
VDES - VNOM
output current path from converter output pins to sense point, 2)
a release of a short-circuit condition, or 3) a release of a cur-
rent 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.
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 cir-
cuit diagram which details the input filtering and voltage trim-
ming.
Input Filtering and External Capacitance: Figure E
below provides a diagram showing the internal input filter
components. This filter dramatically reduces input terminal rip-
ple current, which otherwise could exceed the rating of an
external electrolytic input capacitor. The recommended exter-
nal input capacitance is specified in the “Input Characterisitcs”
section. More detailed information is available in the applica-
tion note titled “EMI Characteristics” on the SynQor website.
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48Vin 12Vout 12.5A
Vin External
Input
Filter
Trim
Vin(+)
Iload
Cload
C1
L
C2
Vout(+)
Rtrim-up
or
Rtrim-down
Vsense(+)
ON/OFF
Vin(_)
Vin(+)
Vin(_)
Vout(_)
Vsense(_)
Electrolytic
Capacitor
47µF
Figure D: Typical application circuit (negative logic unit, permanently enabled).
Figure E: Internal Input Filter Diagram (component values listed on page 3).
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 con-
verter from overheating. In all, there are seven ways that the
converter can be shut down, initiating a Startup Inhibit Period:
• 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:
Before time t0, when the input voltage is below the UVL thresh-
old, the unit is disabled by the Input Under-Voltage Lockout fea-
ture. 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 can-
not 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.
FULL FEATURE APPLICATION NOTES
This section provides some basic application information for the
full-feature version of the
Power
Qor series converter. The pin-out
configuration for these optional feature pins is shown on page
2, and the part numbering format is shown on the last page of
this specification sheet.
All units in this product family include back-drive protection to
simplify the use of multiple converters in a parallel or sequenc-
ing application. However, any voltage applied to the output of
the converter should be kept below 120% of the rated output
voltage of the converter.
In addition to back-drive protection, these units include the fol-
lowing features (pins):
Current Share (pin 3): The active current share feature
allows for N+1 and parallel applications. To achieve load shar-
ing, directly connect the I share pins of multiple units. The load
current will share equally among the multiple units (±5% at full
rated current). It is important that the Vin(-) pins of the sharing
units be directly connected and NOT placed outside of an EMI
filter or other impedance path. The voltage at the I Share pin
will range from 0 to 5 volts (at full rated current), referenced to
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48Vin 12Vout 12.5A
Under-Voltage
Lockout Turn-On
Threshold
ON/OFF
(pos logic)
Figure F: Startup Inhibit Period (turn-on time not to scale)
Vout
Vin
200ms 200ms
200ms
(typical start-up
inhibit period)
t0t1t2t
20ms (typical
turn on time)
ON ON ON
OFF OFF
the primary-side ground, Vin(-).
Start Sync (pin B): The Start Synchronization pin will allow
a more consistent start-up sequence. To operate this feature,
connect together the Start-Sync pins of multiple current-sharing
units. This will permit immediate start-up with loads greater than
the current limit of a single unit. Without this connection, any
set of converters attempting to asynchronously start (or re-start)
with a load greater than the current limit of a single unit will
"hiccup". This “hiccup” mode will continue until one converter
attempts a start at the same time as the minimum number of
additional units necessary to sustain the load condition. For
example, three 50 amp units starting into a 90 amp load would
require two units to simultaneously attempt a start. The Start
Sync connection synchronizes these starting attempts and pro-
vides a more consistent and reliable start-up sequence. For
details about the "hiccup mode" or repeated startup attempts,
please see the "Startup Inhibit Period" note in this Technical
Specification.
Clock Sync (pin A): The External Clock Synchronization pin
provides the ability for the user to control the EMI signature and
synchronize sensitive circuitry to quiet periods in the converter
operation. With this option, the converter can be synchronized
to an external clock signal whose frequency is greater than that
of the free-running internal clock. However, substantially raising
the converter’s frequency will reduce its efficiency. Therefore,
the recommended frequency range for the external clock syn-
chronization signal applied to this pin would be the lowest
value possible without dropping below the minimum frequen-
cies listed below:
275 KHz for the 1.5V and 3.3V units
225 KHz for the 1.8V and 2.0V units
255 KHz for the 2.5V, 5V, 12V and 15V units
The following requirements should also be met:
• The external clock signal should be referenced to the
negative input voltage, Vin(-).
• The high level of the signal should be between 3.5V
and 5.0V.
• The low level should be between -0.5V and +1.2V.
• Do not apply a clock signal lower than the specified
frequency.
OR Drive (pin C): This pin provides a signal which can be
used to drive an OR-ing FET and/or an auxiliary external con-
trol circuitry. This pin may also be used as a basic "Power-
Good" signal. This pin is referenced to the secondary-side
ground, Vsense(-). The voltage at this pin tracks the output volt-
age but has a value several times higher. For example, during
normal operation the OR Drive voltage is at least high enough
to fully gate on a standard MOSFET, whose source voltage is
equal to the output voltage of the converter. With nominal out-
put voltage, the OR Drive signals are listed in the table below
for each output voltage. An internal 2.7 KΩsource resistance
will limit the current drawn from this pin. However, the user is
responsible for the overvoltage protection of the MOSFET or
other external circuitry driven by this voltage. It is recom-
mended that the user include a zener diode between the gate
and source of the external MOSFET(s) driven by the OR Drive
pin. For more information, refer to the Full Feature Application
Note found on the SynQor web site (www.synqor.com).
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48Vin 12Vout 12.5A
OR-Drive Voltages
Vout No Load Full Load
1.2 TBD TBD
1.5 912
1.8 11 14
2.0 11 16
2.5 13 21
3.3 13 16
5.0 19 20
12 24 26
15 26 28
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48Vin 12Vout 12.5A
PART NUMBERING SYSTEM
The part numbering system for SynQor’s
Power
Qor DC/DC
converters follows the format shown in the example below.
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 avail-
able in stock for evaluation and prototype quantities.
Application Notes
A variety of application notes and technical white papers
can be downloaded in pdf format at www.synqor.com.
ORDERING INFORMATION
The tables below show the valid model numbers and order-
ing 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.
The following option choices must be included in place of
the
x y z
spaces in the model numbers listed above.
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.
Contact SynQor for further information:
Phone: 978-849-0600
Toll Free: 888-567-9596
Fax: 978-849-0602
E-mail: sales@synqor.com
Web: www.synqor.com
Address: 155 Swanson Road
Boxborough, MA 01719
Output Max Output
Voltage Current
PQ48015HGA40xyz 35 - 75 V 1.5 V 40 A
PQ48018HGA40xyz 35 - 75 V 1.8 V 40 A
PQ48020HGA40xyz 35 - 75 V 2.0 V 40 A
PQ48025HGA40xyz 35 - 75 V 2.5 V 40 A
PQ48033HGA40xyz 35 - 75 V 3.3 V 40 A
PQ48050HGA30xyz 35 - 75 V 5.0 V 30 A
PQ48120HGA12xyz 35 - 75 V 12 V 12.5 A
PQ48150HGA10xyz 35 - 75 V 15 V 10 A
Model Number
Input Voltage
Enable Pin Feature
Logic Length Set
P - Positive
N - Negative
K - 0.110"
N - 0.145"
R - 0.180"
Y - 0.250"
S - Standard
F - Full Feature
Options Description: x y z
PQ 48 120 H G A 12 N K S
Product Family
Package Size
Performance Level
Thermal Design
Output Current
Options (see
Ordering Information)
Input Voltage
Output Voltage
