Part No. 02-GAQ-01 Rev. 3.0 041405
WWW.GALAXYPWR.COM
GAQW5V020 1
Galaxy Power Inc. 155 Flanders Road Westborough, MA 01581 Telephone: 508-870-9775 Fax: 508-870-9796 e-mail: info@galaxypwr.com
The Aquarius Series is the
highest power eighth-brick DC/DC
converter in the industry.
Industry Standard Pinout and Footprint
No Heat Sink Required
Very Low Common-mode Noise for a
Commercial DC/DC Converter
Two-stage Input Filter
Constant Switching Frequency
Remote Sense
Single Board Design
Very Low Parts Count
Two Year Warranty
Control Functions
Uses Patented Power Supply Control
and Architecture
Microprocessor Controlled
Primary-side Enable, Choice of Logic
Protection Features
Over Temperature Protection
Over Voltage Protection
Over Current Protection
Over/Under Input Voltage Protection
Typical Characteristics
Output Setpoint Accuracy: 1%
Load Regulation: 0.2%
Line Regulation: 0.2%
Regulation over Line, Load, and
Temperature: 2%
Low Output Ripple
Output Trim
Aquarius
48V Input, 5.0VDC, 20A Output
The Aquarius Series of eighth-
brick DC/DC converters in
Galaxy's CoolConverterTM line
provides both exceptional
performance and high density.
GAQW5V020 Features:
48V Input
5.0VDC, 20A Output
High Efficiency:
89% at 5.0V, 20A
91% at 5.0V, 10A
ISO 9001 CERTIFIED ORGANISATION
Certified to ISO 9001:2000
Eighth-brick
Eighth-brick
Eighth-brick
Quarter-brick
Quarter-brick
Half-brick
Half-brick
SIP
SIP
3-Quarter-brick
3-Quarter-brick
GAQW5V020 2
WWW.GALAXYPWR.COM
Part No. 02-GAQ-01 Rev. 3.0 041405
Galaxy Power Inc. 155 Flanders Road Westborough, MA 01581 Telephone: 508-870-9775 Fax: 508-870-9796 e-mail: info@galaxypwr.com
General Specifications
V
IN
= 48V
DC
, T
A
@25 C, 300 LFM Airflow, V
OUT
=5.0V
DC
, I
OUT
= Full Load unless otherwise noted.
Available output power depends on ambient temperature and good thermal management. (See application graphs for limits.)
Input Characteristics
Parameter
Min
Typ
Max
Units
Operating Input Voltage
36
48
75
V
DC
Input Current
4
A
Input Capacitance
3
F
Input Hysteresis, Low Line
2
V
DC
Output Characteristics
Regulation Over Line, Load & Temperature
4.90
5.10
V
Voltage Ripple
20
mV
RMS
Voltage Ripple, 20MHz BW
50
mV
PP
Current Range
0
20
A
Current Limit Inception
20.6
28
A
Short Circuit Current, Peak
1
40
A
Output Transient Response, 50% to 75% load change, 1A/sec
2
8
%V
OUT
Settling Time to 1%
200
S
Turn-on Time to 98%Vnom
35
mS
Output Overshoot at Turn-on
0
%V
OUT
Trim Range
70
110
%V
OUT
Overvoltage Protection, Latching
130
%V
OUT
Isolation
Isolation Test Voltage, Input/Output (Basic)
2250
V
DC
Isolation Resistance
10
M
Features
Overtemperature Protection, Thermal Sensor, Latching
3
110
C
Switching Frequency, Fixed
250
kHz
Notes:
1. During short circuit, converter will shut down and attempt to restart once per second. The average current during this condition will be very low
and the device can be safely left in this condition continuously.
2. Limited by output energy storage. For improved performance see Tuned (T) model information.
3. PCB less than 130 C
General Specifications
Operating Temperature
40 C to +100 C
Storage Temperature
55 C to +125 C
Relative Humidity
10% to 95% RH,
Non-condensing
Vibration
2 to 9Hz, 3mm disp.,
9 to 200Hz, 1g
Material Flammability
UL V-0
Weight
27 grams
MTBF
Telcordia (Bellcore)
2.2 million hours
Approvals and Standards
UL and c-UL Recognized Component, TUV**,
UL60950, CSA 22.2 No. 950, IEC/EN 60950
EMC Characteristics:
Designed to meet emission and immunity
requirements per EN55022, CISPR 22, Class B,
and CISPR 24.
** An external fuse shall be used to comply with the requirements.
Part No. 02-GAQ-01 Rev. 3.0 041405
WWW.GALAXYPWR.COM
GAQW5V020 3
Galaxy Power Inc. 155 Flanders Road Westborough, MA 01581 Telephone: 508-870-9775 Fax: 508-870-9796 e-mail: info@galaxypwr.com
C
ool
C
onverter
TM
Galaxy's proprietary CoolConverterTM provides:
Patented single-stage power conversion architecture,
control, and magnetic design allow unprecedented power
density and efficiency in an isolated power supply.
An advanced microcontroller reduces parts count while
adding features, performance, and flexibility in the design.
Low common-mode noise as a result of lower capacitance
in the transformer from balanced winding design.
Protection and Control
Valid Input Voltage Range:
The converter measures the input voltage and will
not allow operation outside of the input voltage
specification. As shown by the graphs, hysteresis is
added to both the high and low voltage to prevent
the converter from turning on and off repeatedly
when the voltage is held near either voltage extreme.
At low line this assures the maximum input current is
not exceeded; at high line this assures the semicon-
ductor devices in the converter are not damaged by
excessive voltage stress.
ON/OFF Logic Option:
The ON/OFF control logic can be either Negative
(standard) or Positive to enable the converter. For
Negative logic the ON/OFF pin is brought to below
1.0V with respect to the INPUT pin to enable the
converter. The pull down must be able to sink
100A. For Positive logic the ON/OFF pin is brought
to greater than 4.0V with respect to the INPUT pin
and be limited to less than 10V. To request the
Positive logic version, add the suffix (P) to the stan-
dard part number. The ON/OFF pin has a built-in pull
up resistor of approximately 100k to +5V.
Application Notes
Undervoltage Hysteresis
1.0
0
30
34
37
Input Voltage (V)
Output V
oltage
Normalized
36
32
33
35
31
Overvoltage Hysteresis
1.0
0
76.5
78.5
80.5
Input Voltage (V)
Output V
oltage
Normalized
79.5
77.5
78
80
79
77
GAQW5V020 4
WWW.GALAXYPWR.COM
Part No. 02-GAQ-01 Rev. 3.0 041405
Galaxy Power Inc. 155 Flanders Road Westborough, MA 01581 Telephone: 508-870-9775 Fax: 508-870-9796 e-mail: info@galaxypwr.com
R
TRIM-UP
=
5.0 (100+%)
(100+2%)
5.11k
1.225%
%
Output Over Voltage Protection:
The output voltage is constantly monitored by the
microprocessor with a redundant secondary-side
measurement circuit that both shuts down the duty
cycle and triggers the microprocessor to shut down.
If the output voltage exceeds the over-voltage specifi-
cation, the microprocessor will latch the converter off.
To turn the converter on requires either cycling the
ON/OFF pin or power to the converter. This ad-
vanced feature prevents the converter from damaging
the load if there is a converter failure or application
error. If non-latching is required, consult factory.
Thermal Shutdown:
The printed circuit board temperature is measured
using a semiconductor sensor. If the maximum rated
temperature is exceeded, the converter is latched off.
To re-enable the converter requires cycling the ON/
OFF pin or power to the converter. If non-latching is
required, consult factory.
Control Options:
As the behavior of the circuit is determined by
firmware in the microcontroller, specific customer
requirements such as
non-latching thermal protection
custom valid input voltage range
controlled delay from initiating an ON/OFF signal
for power sequencing
can be accomplished with no change to hardware.
The standard behavior was chosen based on system
design experience but we understand that customers
often have their own requirements.
Please consult Galaxy Power for your special needs.
Remote Sense:
The output voltage is regulated at the point where
the sense pins connect to the power output pins.
Total sense compensation should not exceed 0.4V or
10% of Vout, whichever is greater.
Safety:
An external input fuse must always be used to meet
these safety requirements.
External Output Trimming
Application Notes
+Sense
Trim
Sense
Trim
Up
Trim
Down
10K
Trimpot
R
TRIM-DOWN
=
100
2
5.11k
%
{ }
Trim-up
Trim-down
{ }
Trim:
To trim the output voltage higher, connect the
required trim resistor from the Trim pin to the
+Sense pin. To trim the output voltage lower, con-
nect the required trim resistor from the Trim pin to
the Sense pin.
Decrease in Output Voltage (%)
1000
100
10
0
1
2
3
4
5
6
7
8
9
10
T
rim Resistance (k
)
Trim-down
Increase in Output Voltage (%)
10000
1000
100
0
1
2
3
4
5
6
7
8
9
10
T
rim Resistance (k
)
5.0V Trim-up
Part No. 02-GAQ-01 Rev. 3.0 041405
WWW.GALAXYPWR.COM
GAQW5V020 5
Galaxy Power Inc. 155 Flanders Road Westborough, MA 01581 Telephone: 508-870-9775 Fax: 508-870-9796 e-mail: info@galaxypwr.com
GAQW5V020 Operation
Efficiency
93
91
89
87
85
83
81
79
77
75
0
20
Output Current (A)
Ef
ficiency (%)
36V Vin
48V Vin
75V Vin
10
15
5
Power Dissipation
14
12
10
8
6
4
2
0
0
20
Output Current (A)
Power Dissipation (W)
36V Vin
48V Vin
75V Vin
10
5
15
Start Up
1) Vout 2V 4mS/div
2) Iout 10A/div
3) Enable 5V/div
CH3
CH1
CH2
Voltage Ripple
1) Vout 20mV/div 2S/div
10F ext cap 20MHz BW
Transient Response
1) Vout 200mV/div 200S/div
2) Iout 10A/div
CH2
CH1
Line/Load Regulation
5.04
5.02
5.00
4.98
0
10
Output Current (A)
Output V
oltage (V)
36V Vin
48V Vin
75V Vin
15
5
20
Setpoint Accuracy 0.1120%
Line Regulation 0.0180%
Load Regulation 0.0090%
Line & Load Regulation 0.0260%
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