SQE48T20120 DC-DC Converter
36-75 VDC Input; 12VDC @ 20A Output
Features
•
•
•
•
•
•
•
•
•
•
•
•
•
Industry-standard quarter-brick pinout
Delivers 240W at 94.2% efficiency
Withstands 100V input transient for 100ms
Fixed-frequency operation
On-board input differential LC-filter
Start-up into pre-biased load
No minimum load required
Meets Basic Insulation requirements
Fully protected (OTP, OCP, OVP, UVLO)
Positive or negative logic ON/OFF option
Low height of 0.44” (11.18mm)
Weight: 32g w/o baseplate, 40g with baseplate
High reliability: MTBF = 14.3 million hours,
calculated per Telcordia SR-332, Method I Case 1
•
Approved to the following Safety Standards:
UL/CSA60950-1, EN60950-1, and IEC60950-1
(In process)
•
Designed to meet Class B conducted emissions per
FCC and EN55022 when used with external filter
•
All materials meet UL94, V-0 flammability rating
Applications
•
•
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Intermediate Bus Architectures
Data communications/processing
LAN/WAN
Servers, Workstations
Benefits
•
High efficiency – no heat sink required
th
•
Industry-standard 1/8 brick footprint: 0.896” x
2
2.30” (2.06 in ) - 38% smaller than conventional
quarter-bricks
Description
1
The new high performance 20A SQE48T20120 DC-DC converter provides a high efficiency single output, in a 1/8
brick package that is only 62% the size of the industry-standard quarter-brick. Specifically designed for operation
in systems that have limited airflow and increased ambient temperatures, the SQE48T20120 converter utilizes the
same pinout and Input/Output functionality of the industry-standard quarter-bricks. In addition, a heat spreader
feature is available (-xDxBx suffix) that provides an effective thermal interface for coldplate and heat sinking
options.
The SQE48T20120 converter thermal performance is accomplished through the use advanced circuits, packaging,
and processing techniques to achieve ultra-high efficiency, excellent thermal management, and a low-body profile.
Operating from a wide-range 36-75V input, the SQE48T20120 converter provides a fully regulated 12V output
voltage. Employing a standard power pinout, the SQE48T20120 converter is an ideal drop-in replacement for
existing high current quarter-brick designs. Inclusion of this converter in a new design can result in significant
board space and cost savings. The designer can expect reliability improvement over other available converters
because of the SQE48T20120’s optimized thermal efficiency.
th
1
Baseplate/heat spreader option (suffix ‘-xDxBx’) facilitates heatsink mounting to further enhance the unit’s thermal capability.
Rev. 2.0, 24-OCT-11
www.power-one.com
Page 1 of 14
SQE48T20120 DC-DC Converter
36-75 VDC Input; 12VDC @ 20A Output
Electrical Specifications
Conditions: T
A
= 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 48 VDC, Cin=100 µF, unless otherwise specified.
Parameter
Absolute Maximum Ratings
Input Voltage
Operating Temperature
Continuous
Notes
Min
-0.3
Ambient (T
A
)
-40
-40
-40
-55
2,250
Typ
Max
80
100
85
125
105
125
Units
VDC
VDC
°C
°C
°C
°C
VDC
Transient (100ms)
(Note: 1)
Component (T
C
)
Baseplate (T
B
)
(See Derating Curves)
Storage Temperature
Isolation Characteristics
I/O Isolation
Isolation Capacitance
Isolation Resistance
Input to Baseplate
Output to Baseplate
10
1,500
1,500
450
2
2
1, 200
pF
MΩ
VDC
VDC
kHz
%
%
130
%
°C
ms
25
15
25
15
0.8
20
20
0.8
ms
ms
ms
ms
VDC
VDC
VDC
VDC
Feature Characteristics
Switching Frequency
Output Voltage Trim Range
Remote Sense Compensation
Output Overvoltage Protection
Over Temperature Shutdown
Auto-Restart Period
Turn-On Time from Vin
n/a
n/a
(Non-latching)
(Non-latching)
110
(Note: 1)
120
130
250
22
12
22
12
Component (T
C
)
Applies to all protection features
Time from UVLO to Vo=90%V
OUT
(
NOM
)
Resistive load
Turn-On Time from ON/OFF Control
Time from ON to Vo=90%V
OUT
(
NOM
)
Resistive load
Time from UVLO to Vo=90%V
OUT
(
NOM
)
Turn-On Time from Vin
(w/ Co max.) Resistive load, C
EXT
=10,000µF load
Turn-On Time from ON/OFF Control
Time from ON to Vo=90%V
OUT
(
NOM
)
(w/ Co max.) Resistive load, C
EXT
=10,000µF load
ON/OFF Control (Positive Logic)
Converter Off (logic low)
Converter On (logic high)
ON/OFF Control (Negative Logic)
Converter Off (logic low)
Converter On (logic high)
Additional Notes:
1
Reference Figure E for component (T
C
and T
B
) locations.
2
This functionality not provided, however the unit is fully regulated.
-20
2.4
2.4
-20
Rev. 2.0, 24-OCT-11
www.power-one.com
Page 2 of 14
SQE48T20120 DC-DC Converter
36-75 VDC Input; 12VDC @ 20A Output
Electrical Specifications (continued)
Conditions: T
A
= 25 ºC, Airflow = 300 LFM (1.5 m/s), Vin = 48 VDC, Cin=100 µF, unless otherwise specified.
Parameter
Input Characteristics
Operating Input Voltage Range
Input Undervoltage Lockout
Turn-on Threshold
Turn-off Threshold
Lockout Hysteresis Voltage
Maximum Input Current
Input Standby Current
Input No Load Current (No load on the output)
Input Reflected-Ripple Current,
Input Reflected-Ripple Current,
Input Voltage Ripple Rejection
Notes
Min
36
31.5
30
1.5
Typ
48
34.5
32
2.0
3
Max
75
35.5
34.0
2.5
7.3
5
130
900
325
14
5
Units
VDC
VDC
VDC
VDC
ADC
mA
mA
mA
PK-PK
mA
RMS
mA
PK-PK
mA
RMS
dB
VDC
mV
mV
VDC
mV
PK-PK
V
RMS
µF
mOhm
ADC
ADC
A
RMS
Po = 240W @ 36VDC In
Vin = 48V, converter disabled
Vin = 48V, converter enabled
Vin = 48V, 25 MHz bandwidth,
Po=240W (Figs. 14,15, 16)
120 Hz
V
IN
=48V, I
OUT
=0Amps, T
A
=25°C
I
OUT
=20Amps, T
A
=25°C
V
IN
=48V, , T
A
=25°C
Over line, load and temperature
I
OUT
=20Amps,
C
EXT
=10 µF tantalum + 1 µF ceramic
I
OUT
=20Amps (resistive)
C
EXT
ESR
0
1
0
1
50
70
760
265
8
2
45
ic
i
S
Output Characteristics
Output Voltage Setpoint
Output Regulation
Over Line
Over Load
Output Voltage Range
Output Ripple and Noise – 25 MHz bandwidth
Admissible External Load Capacitance
Output Current Range
Current Limit Inception
RMS Short-Circuit Current
Non-latching
Non-latching Short = 10 mΩ
±12
±6
11.64
50
25
±24
±12
12.36
100
50
10,000
20
25
2.4
29
5
11.76
12.00
12.24
22
Dynamic Response
Load Change 50%-75%-50% of I
OUT
Max
(di/dt = 0.1
A/μs)
Settling Time to 1% of V
OUT
C
EXT
= 10µF tantalum + 1µF ceramic
75
30
94.2
94
140
50
mV
µs
%
%
Efficiency
@ 100% Load
@ 60% Load
Additional Notes:
1
48V
IN
, T
A
=25°C, 300LFM
See
“Input Output Impedance”,
Page 4.
Rev. 2.0, 24-OCT-11
www.power-one.com
Page 3 of 14
SQE48T20120 DC-DC Converter
36-75 VDC Input; 12VDC @ 20A Output
Environment and Mechanical Specifications
Parameter
Environmental
Operating Humidity
Storage Humidity
Mechanical
Weight
Vibration
Shocks
Reliability
MTBF
EMI and Regulatory Compliance
Conducted Emissions
CISPR 22 B with external EMI filter network
Telcordia SR-332, Method I Case 1
50% electrical stress, 40°C components
14.3
MHrs
Non-condensing
Non-condensing
Without baseplate
With baseplate
GR-63-CORE, Sect. 5.4.2
Half Sinewave, 3-axis
1
50
32
40
95
95
%
%
g
g
g
g
Notes
Min
Typ
Max
Units
Operations
Input and Output Impedance
These power converters have been designed to be
stable with no external capacitors when used in low
inductance input and output circuits.
However, in some applications, the inductance
associated with the distribution from the power
source to the input of the converter can affect the
stability of the converter. A 100 µF electrolytic
capacitor with adequate ESR based on input
impedance is recommended to ensure stability of the
converter.
In many end applications, a high capacitance value
is applied to the converter’s output via distributed
capacitors. The power converter will exhibit stable
operation with external load capacitance up to
10,000 µF.
ON/OFF (Pin 2)
The ON/OFF pin is used to turn the power converter
on or off remotely via a system signal. There are two
remote control options available, positive and
negative logic, with both referenced to Vin(-). A
typical connection is shown in Figure A.
The positive logic version turns on when the ON/OFF
pin is at a logic high or left open and turns off when it
is at a logic low. See the Electrical Specifications for
logic high/low definitions.
Fig. A: Typ. Circuit configuration for ON/OFF function.
The negative logic version turns on when the
ON/OFF pin is at a logic low and turns off when the
pin is at logic high. To enable automatic power up of
the converter without the need of an external control
signal the ON/OFF pin can be hard wired directly to
Vin(-) for N and left open for P version.
The ON/OFF pin is internally pulled up to 5V through
a resistor. A properly de-bounced mechanical switch,
open-collector transistor, or FET can be used to
drive the input of the ON/OFF pin. The device must
be capable of sinking up to 0.2 mA at a low level
voltage of
≤
0.8 V. An external voltage source (±20 V
maximum) may be connected directly to the ON/OFF
input, in which case it must be capable of sourcing or
sinking up to 1 mA depending on the signal polarity.
Rev. 2.0, 24-OCT-11
www.power-one.com
Page 4 of 14
SQE48T20120 DC-DC Converter
36-75 VDC Input; 12VDC @ 20A Output
See the Startup Information section for system timing
waveforms associated with use of the ON/OFF pin.
Protection Features
Input Undervoltage Lockout (UVLO)
Input undervoltage lockout is standard with this
converter. The converter will shut down when the
input voltage drops below a pre-determined voltage.
The input voltage must be typically 35V for the
converter to turn on. Once the converter has been
turned on, it will shut off when the input voltage
drops typically below 33V. This feature is beneficial
in preventing deep discharging of batteries used in
telecom applications.
Output Overcurrent Protection (OCP)
The converter is protected against overcurrent or
short circuit conditions. Upon sensing an overcurrent
condition, the converter will shut down after entering
the constant current mode of operation, regardless of
the value of the output voltage.
Once the converter has shut down, it will enter
hiccup mode with attempt to restart every 260 ms
until the overload or short circuit conditions are
removed.
Output Overvoltage Protection (OVP)
The converter will shut down if the output voltage
across Vout(+) and Vout(-) exceeds the threshold of
the OVP circuitry. The OVP circuitry contains its own
reference, independent of the output voltage
regulation loop. Once the converter has shut down, it
will attempt to restart every 260 ms until the OVP
condition is removed.
Overtemperature Protection (OTP)
The converter will shut down under an
overtemperature condition to protect itself from
overheating caused by operation outside the thermal
derating curves, or operation in abnormal conditions.
The converter will automatically restart after it has
cooled to a safe operating temperature.
Safety Requirements
The
converters
are
safety
approved
to
UL/CSA60950-1, EN60950-1, and IEC60950-1.
Basic Insulation is provided between input and
output.
The converters have no internal fuse. To comply
with safety agencies requirements, an input line fuse
must be used external to the converter. A 10 A fuse
is recommended for use with this product. The fuse
must not be placed in the grounded input line.
The SQE48 converter is UL approved for a maximum fuse
rating of 15 Amps.
Electromagnetic Compatibility (EMC)
EMC requirements must be met at the end-product
system level, as no specific standards dedicated to
EMC characteristics of board mounted component
dc-dc converters exist. However, Power-One tests its
converters to several system level standards,
primary of which is the more stringent EN55022,
Information
technology
equipment
-
Radio
disturbance characteristics - Limits and methods of
measurement.
An effective internal LC differential filter significantly
reduces input reflected ripple current, and improves
EMC.
With the addition of an external filter, the
SQE48T20120 converter will pass the requirements
of Class B conducted emissions per EN55022 and
FCC requirements. Refer to Figures 18 – 19 for
typical performance with external filter.
Rev. 2.0, 24-OCT-11
www.power-one.com
Page 5 of 14
