The high temperature 30A SQE48 Series of DC-DC converters
provides a high efficiency single output, in a 1/8th 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 SQE48T30
converters utilize the same pinout and functionality of the industrystandard quarter-bricks.
The 30 A SQE48 Series converters provide thermal performance in
high temperature environments that exceeds most competitors'
30A quarter-bricks. This performance is accomplished through the
use of patented/patent-pending circuits, packaging, and
processing techniques to achieve ultra-high efficiency, excellent
thermal management, and a low-body profile.
RoHS lead-free solder and lead-solder-exempted products are
available
Delivers up to 30 A
Industry-standard quarter-brick pinout
Outputs available: 3.3, 2.5, 1.8, 1.5, and 1.2 VDC
On-board input differential LC-filter
Startup into pre-biased load
No minimum load required
Weight: 0.72 oz [20.6 g]
Meets Basic Insulation requirements of EN60950
Withstands 100 V input transient for 100 ms
Fixed-frequency operation
Fully protected
Remote output sense
Positive or negative logic ON/OFF option
Latching and non-latching protection available
Output voltage trim range: +10%/−20% with industry-standard
trim equations (except 1.2 Vout)
High reliability: MTBF = 15.75 million hours, calculated per
Telcordia TR-332, Method I Case 1
UL60950 recognized in US and Canada and certified per
IEC/EN60950
Designed to meet Class B conducted emissions per FCC and
EN55022 when used with external filter
All materials meet UL94, V-0 flammability rating
Low-body profile and the preclusion of heat sinks minimize
impedance to system airflow, thus enhancing cooling for both
upstream and downstream devices. The use of 100% automation
for assembly, coupled with advanced electronic circuits and
thermal design, results in a product with extremely high reliability.
Operating from a 36-75 V input, the SQE48T30 converters provide
any standard output voltage from 3.3 V down to 1.2 V that can be
trimmed from –20% to +10% of the nominal output voltage (± 10%
for output voltage 1.2 V), thus providing outstanding design
flexibility.
With standard pinout and trim equations, the SQE48 Series
converters are perfect drop-in replacements for existing 30 A
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 SQE48 Series’ optimized thermal
efficiency.
Telecommunications
Data Communications
Wireless Communications
Servers, workstations
High efficiency – no heat sink required
Higher current capability at elevated temperatures than
competitors’ 30 A quarter-bricks
Industry standard 1/8th brick footprint: 0.896” x 2.30” (2.06
in2), 38% smaller than conventional quarter-bricks
North America
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Europe, Middle East
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Conditions: TA = 25 º C, Airflow = 300 LFM (1.5 m/s), Vin = 48 VDC, Cin=33 µ F, unless otherwise specified.
PARAMETER
Notes
MIN
TYP
MAX
UNITS
Absolute Maximum Ratings
Input Voltage
0
80
VDC
Operating Ambient Temperature
Continuous
-40
85
°C
Storage Temperature
-55
125
°C
Isolation Characteristics
I/O Isolation
2250
Isolation Capacitance
VDC
200
Isolation Resistance
pF
10
MΩ
Feature Characteristics
Switching Frequency
Output Voltage Trim Range1
Remote Sense
Compensation1
Output Overvoltage Protection
440
kHz
Industry-std. equations (3.3 – 1.5 V)
-20
+10
%
Use trim equation on Page 6 (1.2 V)
-10
+10
%
Percent of VOUT(NOM)
+10
%
Latching or Non-latching ( 3.3 – 1.8 V)
117
122
130
%
Latching or Non-latching (1.5 -1.2 V)
122
128
140
%
125
°C
Peak amplitude
1
ADC
Peak duration
50
μs
Converter Off;
external voltage 5 VDC
10
Auto-Restart Period
Applies to all protection features
200
ms
Turn-On Time
See Figs. E, F, and G
3
ms
Overtemperature Shutdown (PCB)
Non-latching
Peak Back-drive Output Current (Sinking current
from external source) during startup into prebiased output
Back-drive Output Current (Sinking Current from
external source)
30
mADC
ON/OFF Control (Positive Logic)
Converter Off (logic low)
-20
0.8
VDC
Converter On (logic high)
2.4
20
VDC
Converter Off (logic high)
2.4
20
VDC
Converter On (logic low)
-20
0.8
VDC
ON/OFF Control (Negative Logic)
Input Characteristics
Operating Input Voltage Range
36
48
75
VDC
33
34
35
VDC
31
32
Input Undervoltage Lockout
Turn-on Threshold
Turn-off Threshold
33
VDC
100
VDC
VOUT = 3.3 VDC
3.1
ADC
VOUT = 2.5 VDC
2.4
ADC
VOUT = 1.8 VDC
1.7
ADC
VOUT = 1.5 VDC
1.5
ADC
VOUT = 1.2 VDC
1.2
ADC
Input Voltage Transient
100 ms
Maximum Input Current
30 ADC Out @ 36 VDC In
Input Stand-by Current
Vin = 48V, converter disabled
2
mA
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Input No Load Current (0 load on the output)
Input Reflected-Ripple Current, is
Input Voltage Ripple Rejection
Vin = 48V, converter enabled
VOUT = 3.3 VDC
42
mA
VOUT = 2.5 VDC
34
mA
VOUT = 1.8 VDC
30
mA
VOUT = 1.5 VDC
28
mA
VOUT = 1.2 VDC
27
mA
VOUT = 3.3 VDC
8
mAPK-PK
VOUT = 2.5 VDC
6
mAPK-PK
VOUT = 1.8 VDC
6
mAPK-PK
VOUT = 1.5 VDC
6
mAPK-PK
VOUT = 1.2 VDC
6
mAPK-PK
VOUT = 3.3 VDC
91
dB
VOUT = 2.5 VDC
60
dB
VOUT = 1.8 VDC
70
dB
VOUT = 1.5 VDC
65
dB
VOUT = 1.2 VDC
65
dB
Vin = 48V, 25 MHz bandwidth
120 Hz
Output Characteristics
External Load Capacitance
Plus full load (resistive)
Output Current Range
0
Current Limit Inception
Non-latching
Peak Short-Circuit Current
Non-latching, Short = 10 mΩ
RMS Short-Circuit Current
Non-latching
31.5
36.5
6
Output Voltage Set Point (no load)2
30,000
μF
30
ADC
42
ADC
46
A
8
Arms
+1
%Vout
±2
±5
mV
±2
±5
mV
+1.5
%Vout
-1
Output Regulation Over Line
Over Line
Over Load
Output Voltage Range
Output Ripple and Noise – 25 MHz bandwidth
Over line, load and temperature2
-1.5
Full load + 10 μF tantalum + 1 μF ceramic
VOUT = 3.3 VDC
40
75
mVPK-PK
VOUT = 2.5 VDC
35
60
mVPK-PK
VOUT = 1.8 VDC
30
50
mVPK-PK
VOUT = 1.5 VDC
25
45
mVPK-PK
VOUT = 1.2 VDC
20
40
mVPK-PK
Co = 1 μF ceramic (Fig. 3.3V.9)
303
mV
Co = 1 μF ceramic (Fig. 3.3V.9)
150
mV
15
μs
VOUT = 3.3 VDC
90.5
%
VOUT = 2.5 VDC
89.0
%
VOUT = 1.8 VDC
86.5
%
Dynamic Response
Load Change 10A-20A-10A
di/dt = 0.1 A/μs
di/dt = 5 A/μs
Settling Time to 1% of Vout
Efficiency
100% Load
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50% Load
VOUT = 1.5 VDC
85.0
%
VOUT = 1.2 VDC
83.0
%
VOUT = 3.3 VDC
92.0
%
VOUT = 2.5 VDC
90.5
%
VOUT = 1.8 VDC
88.5
%
VOUT = 1.5 VDC
87.0
%
VOUT = 1.2 VDC
85.0
%
Additional Notes:
1Vout can be increased up to 10% via the sense leads or up to 10% via the trim function. However, the total output voltage trim from all sources
should not exceed 10% of V
(NOM), in order to ensure specified operation of overvoltage protection circuitry.
OUT
2Operating
3See
ambient temperature range of -40 º C to 85 º C for converter.
waveforms for dynamic response and settling time for different output voltages
These power converters have been designed to be stable with no external capacitors when used in low inductance input
and output circuits.
In many applications, the inductance associated with the distribution from the power source to the input of the converter
can affect the stability of the converter. The addition of a 33 μF electrolytic capacitor with an ESR < 1 Ω across the input
helps to ensure stability of the converter. In many applications, the user has to use decoupling capacitance at the load. The
power converter will exhibit stable operation with external load capacitance up to 30,000 μF on 3.3 to 1.2 V outputs.
Additionally, see the EMC section of this data sheet for discussion of other external components which may be required for
control of conducted emissions.
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 logic and negative logic, with both referenced to Vin(-). A typical connection is shown in Fig. A.
Fig. A: Circuit configuration for ON/OFF function
The positive logic version turns on when the ON/OFF pin is at a logic high and turns off when at a logic low. The converter
is on when the ON/OFF pin is left open. See the Electrical Specifications for logic high/low definitions.
The negative logic version turns on when the pin is at a logic low and turns off when the pin is at a logic high. The ON/OFF
pin can be hard wired directly to Vin(-) to enable automatic power up of the converter without the need of an external
control signal.
The ON/OFF pin is internally pulled up to 5 V 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. See the Startup
Information section for system timing waveforms associated with use of the ON/OFF pin.
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The remote sense feature of the converter compensates for voltage drops occurring between the output pins of the
converter and the load. The SENSE(-) (Pin 5) and SENSE(+) (Pin 7) pins should be connected at the load or at the point
where regulation is required (see Fig. B).
Fig. B: Remote sense circuit configuration
CAUTION
If remote sensing is not utilized, the SENSE(-) pin must be connected to the Vout(-) pin (Pin 4), and the SENSE(+) pin must
be connected to the Vout(+) pin (Pin 8) to ensure the converter will regulate at the specified output voltage. If these
connections are not made, the converter will deliver an output voltage that is slightly higher than the specified data sheet
value.
Because the sense leads carry minimal current, large traces on the end-user board are not required. However, sense traces
should be run side by side and located close to a ground plane to minimize system noise and ensure optimum
performance.
The converter’s output overvoltage protection (OVP) senses the voltage across Vout(+) and Vout(-), and not across the
sense lines, so the resistance (and resulting voltage drop) between the output pins of the converter and the load should be
minimized to prevent unwanted triggering of the OVP.
When utilizing the remote sense feature, care must be taken not to exceed the maximum allowable output power capability
of the converter, which is equal to the product of the nominal output voltage and the allowable output current for the given
conditions.
When using remote sense, the output voltage at the converter can be increased by as much as 10% above the nominal
rating in order to maintain the required voltage across the load. Therefore, the designer must, if necessary, decrease the
maximum current (originally obtained from the derating curves) by the same percentage to ensure the converter’s actual
output power remains at or below the maximum allowable output power.
The output voltage can be adjusted up 10% or down 20% for Vout ≥ 1.5 V, and 10% for Vout = 1.2 V relative to the rated
output voltage by the addition of an externally connected resistor. For output voltage 3.3 V, trim up to 10% is guaranteed
only at Vin ≥ 40 V, and it is marginal (8% to 10%) at Vin = 36 V.
The TRIM pin should be left open if trimming is not being used. To minimize noise pickup, a 0.1 μF capacitor is connected
internally between the TRIM and SENSE(-) pins.
To increase the output voltage, refer to Fig. C. A trim resistor, RT-INCR, should be connected between the TRIM (Pin 6) and
SENSE(+) (Pin 7), with a value of:
RTINCR
5.11(100 Δ)V ONOM 626
10.22
1.225Δ
[k],
for 3.3 – 1.5 V.
[kΩ] (1.2 V)
where,
RTINCR Required value of trim-up resistor k]
VONOM Nominal value of output voltage [V]
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Δ
(VO-REQ VO-NOM )
X 100
VO -NOM
[%]
VOREQ Desired (trimmed) output voltage [V].
When trimming up, care must be taken not to exceed the converter‘s maximum allowable output power. See the previous
section for a complete discussion of this requirement.
Fig. C: Configuration for increasing output voltage
To decrease the output voltage (Fig. D), a trim resistor, R
, should be connected between the TRIM (Pin 6) and
T-DECR
SENSE(-) (Pin 5), with a value of:
where,
RTDECR Required value of trim-down resistor [kΩ] and Δ is defined above.
Note:
The above equations for calculation of trim resistor values match those typically used in conventional industry-standard quarter-bricks (except for
1.2 V outputs).
Converters with output voltages 1.2 V is available with alternative trim feature to provide the customers with the flexibility of second sourcing has a
character “T” in the part number. The trim equations of “T” version of converters and more information can be found in Application Note for Output
Voltage Trim Function Operation.
Fig. D: Configuration for decreasing output voltage
Trimming/sensing beyond 110% of the rated output voltage is not an acceptable design practice, as this condition could
cause unwanted triggering of the output overvoltage protection (OVP) circuit. The designer should ensure that the
difference between the voltages across the converter’s output pins and its sense pins does not exceed 10% of V OUT(NOM),
or:
[VOUT() VOUT()] [VSENSE() VSENSE()] VO - NOM X 10% [V]
This equation is applicable for any condition of output sensing and/or output trim.
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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 34 V for the converter to turn on. Once the converter has been turned on, it will shut off
when the input voltage drops typically below 32 V. This feature is beneficial in preventing deep discharging of batteries
used in telecom applications.
The converter is protected against overcurrent or short circuit conditions. Upon sensing an overcurrent condition, the
converter will switch to constant current operation and thereby begin to reduce output voltage. When the output voltage
drops below 60% of the nominal value of output voltage, the converter will shut down (Fig x.15).
Once the converter has shut down, it will attempt to restart nominally every 200 ms with a typical 3-5% duty cycle (Fig.
x.16). The attempted restart will continue indefinitely until the overload or short circuit conditions are removed or the output
voltage rises above 40-50% of its nominal value.
Once the output current is brought back into its specified range, the converter automatically exits the hiccup mode and
continues normal operation.
For implementations where latching is required, a “Latching” option (L) is available for short circuit and OVP protections.
Converters with the latching feature will latch off if either event occurs. The converter will attempt to restart after either the
input voltage is removed and reapplied OR the ON/OFF pin is cycled.
The converter will shut down if the output voltage across Vout(+) (Pin 8) and Vout(-) (Pin 4) 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 200 ms until the OVP condition is removed.
For implementations where latching is required, a “Latching” option (L) is available for short circuit and OVP protections.
Converters with the latching feature will latch off if either event occurs. The converter will attempt to restart after either the
input voltage is removed and reapplied OR the ON/OFF pin is cycled.
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 such as system fan failure. The converter with the
non-latching option will automatically restart after it has cooled to a safe operating temperature.
The converters meet North American and International safety regulatory requirements per UL60950 and EN60950. Basic
Insulation is provided between input and output.
To comply with safety agencies’ requirements, an input line fuse must be used external to the converter. The Table below
provides the recommended fuse rating for use with this family of products.
Output Voltage
3.3 V
2.5 V
1.8 V, 1.5 V
1.2 V
Fuse Rating
5A
4A
3A
2.5 A
All SQ converters are UL approved for a maximum fuse rating of 15 A. To protect a group of converters with a single fuse,
the rating can be increased from the recommended values above.
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, Bel Power Solutions 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.
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An effective internal LC differential filter significantly reduces input reflected ripple current, and improves EMC. With the
addition of a simple external filter, all versions of the SQE48-Series of converters pass the requirements of Class B
conducted emissions per EN55022 and FCC requirements. Contact Bel Power Solutions Applications Engineering for
details of this testing.
Startup Information (using negative ON/OFF)
Fig. E: Startup scenario #1
Scenario #1: Initial Startup From Bulk Supply
ON/OFF function enabled, converter started via application of VIN.
See Figure E.
Time
t0
Comments
ON/OFF pin is ON; system front-end power is toggled
on, VIN to converter begins to rise.
t1
VIN crosses undervoltage Lockout protection circuit
threshold; converter enabled.
t2
Converter begins to respond to turn-on command
(converter turn-on delay).
t3
Converter VOUT reaches 100% of nominal value.
For this example, the total converter startup time (t3- t1) is typically
3 ms.
Fig. F: Startup scenario #2
Scenario #2: Initial Startup Using ON/OFF Pin
With VIN previously powered, converter started via ON/OFF pin.
See Figure F.
Time
t0
t1
Comments
VINPUT at nominal value.
Arbitrary time when ON/OFF pin is enabled (converter
enabled).
t2
End of converter turn-on delay.
t3
Converter VOUT reaches 100% of nominal value.
For this example, the total converter startup time (t3- t1) is typically
3 ms.
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Fig. G: Startup scenario #3
Scenario #3: Turn-off and Restart Using ON/OFF Pin
With VIN previously powered, converter is disabled and then
enabled via ON/OFF pin. See Figure G.
Time
t0
t1
Comments
VIN and VOUT are at nominal values; ON/OFF pin ON.
ON/OFF pin arbitrarily disabled; converter output falls
to zero; turn-on inhibit delay period (100 ms typical) is
initiated, and ON/OFF pin action is internally inhibited.
t2
ON/OFF pin is externally re-enabled.
If (t2- t1) ≤ 200 ms, external action of ON/OFF pin
is locked out by startup inhibit timer.
If (t2- t1) > 200 ms, ON/OFF pin action is internally
enabled.
t3
Turn-on inhibit delay period ends. If ON/OFF pin is
ON, converter begins turn-on; if off, converter awaits
ON/OFF pin ON signal; see Figure F.
t4
End of converter turn-on delay.
t5
Converter VOUT reaches 100% of nominal value.
For the condition, (t2- t1) ≤ 200 ms, the total converter startup time
(t5- t2) is typically 203 ms. For (t2- t1) > 200 ms, startup will be
typically 3 ms after release of ON/OFF pin.
The converter has been characterized for many operational aspects, to include thermal derating (maximum load current as
a function of ambient temperature and airflow) for vertical and horizontal mounting, efficiency, startup and shutdown
parameters, output ripple and noise, transient response to load step-change, overload, and short circuit.
All data presented were taken with the converter soldered to a test board, specifically a 0.060” thick printed wiring board
(PWB) with four layers. The top and bottom layers were not metalized. The two inner layers, comprised of two-ounce
copper, were used to provide traces for connectivity to the converter.
The lack of metalization on the outer layers as well as the limited thermal connection ensured that heat transfer from the
converter to the PWB was minimized. This provides a worst-case but consistent scenario for thermal derating purposes.
All measurements requiring airflow were made in the vertical and horizontal wind tunnel using Infrared (IR) thermography
and thermocouples for thermometry.
Ensuring components on the converter do not exceed their ratings is important to maintaining high reliability. If one
anticipates operating the converter at or close to the maximum loads specified in the derating curves, it is prudent to check
actual operating temperatures in the application. Thermographic imaging is preferable; if this capability is not available, then
thermocouples may be used. The use of AWG #40 gauge thermocouples is recommended to ensure measurement
accuracy. Careful routing of the thermocouple leads will further minimize measurement error. Refer to Fig. H for the
optimum measuring thermocouple locations.
Load current vs. ambient temperature and airflow rates are given in Fig. x.1 and Fig. x.2 for vertical and horizontal converter
mounting. Ambient temperature was varied between 25 ° C and 85 ° C, with airflow rates from 30 to 500 LFM (0.15 to 2.5
m/s).
For each set of conditions, the maximum load current was defined as the lowest of:
(i) The output current at which any FET junction temperature does not exceed a maximum specified temperature of 120 ° C
as indicated by the thermographic image, or
(ii) The temperature of the transformer does not exceed 120 ° C, or
(iii) The nominal rating of the converter (30 A on 3.3 to 1.2 V).
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During normal operation, derating curves with maximum FET temperature less or equal to 120 ° C should not be exceeded.
Temperature at both thermocouple locations shown in Fig. H should not exceed 120 ° C in order to operate inside the
derating curves.
Fig. H: Locations of the thermocouple for thermal testing
Fig. x.3 shows the efficiency vs. load current plot for ambient temperature of 25 º C, airflow rate of 300 LFM (1.5 m/s) with
vertical mounting and input voltages of 36 V, 48 V, and 72 V. Also, a plot of efficiency vs. load current, as a function of
ambient temperature with Vin = 48 V, airflow rate of 200 LFM (1 m/s) with vertical mounting is shown in Fig. x.4.
Fig. x.5 shows the power dissipation vs. load current plot for Ta = 25 º C, airflow rate of 300 LFM (1.5 m/s) with vertical
mounting and input voltages of 36 V, 48 V, and 72 V. Also, a plot of power dissipation vs. load current, as a function of
ambient temperature with Vin = 48 V, airflow rate of 200 LFM (1 m/s) with vertical mounting is shown in Fig. x.6.
Output voltage waveforms, during the turn-on transient using the ON/OFF pin for full rated load currents (resistive load) are
shown without and with external load capacitance in Figs. x.7-8, respectively.
Fig. x.11 show the output voltage ripple waveform, measured at full rated load current with a 10 μF tantalum and 1 μF
ceramic capacitor across the output. Note that all output voltage waveforms are measured across a 1 μF ceramic
capacitor.
The input reflected-ripple current waveforms are obtained using the test setup shown in Fig x.12. The corresponding
waveforms are shown in Figs. x.13-14.
Fig. 3.3V.1: Available load current vs. ambient air temperature
and airflow rates for SQE48T30033 converter mounted vertically
with air flowing from pin 3 to pin 1, MOSFET temperature ≤ 120
° C, Vin = 48 V.
Fig. 3.3V.2: Available load current vs. ambient air temperature
and airflow rates for SQE48T30033 converter mounted
horizontally with air flowing from pin 3 to pin 1, MOSFET
temperature ≤ 120 ° C, Vin = 48 V.
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Note: NC – Natural convection
Fig. 3.3V.3: Efficiency vs. load current and input voltage for
SQE48T30033 converter mounted vertically with air flowing from
pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s) and Ta = 25 ° C.
Fig. 3.3V.4: Efficiency vs. load current and ambient temperature
for SQE48T30033 converter mounted vertically with Vin = 48 V
and air flowing from pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s).
Fig. 3.3V.5: Power dissipation vs. load current and input voltage
for SQE48T30033 converter mounted vertically with air flowing
from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s) and Ta = 25
° C.
Fig. 3.3V.6: Power dissipation vs. load current and ambient
temperature for SQE48T30033 converter mounted vertically
with Vin = 48 V and air flowing from pin 3 to pin 1 at a rate of
200 LFM (1.0 m/s).
Fig. 3.3V.7: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V, triggered via
ON/OFF pin. Top trace: ON/OFF signal (5 V/div.). Bottom trace:
Output voltage (1 V/div.). Time scale: 1 ms/div.
Fig. 3.3V.8: Turn-on transient at full rated load current
(resistive) plus 10,000 μF at Vin = 48 V, triggered via ON/OFF
pin. Top trace: ON/OFF signal (5 V/div.). Bottom trace: Output
voltage (1 V/div.). Time scale: 1 ms/div.
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Fig. 3.3V.9: Output voltage response to load current stepchange (10 A – 20 A – 10 A) at Vin = 48 V. Top trace: output
voltage (100 mV/div.). Bottom trace: load current
(10 A/div.). Current slew rate: 0.1 A/μs. Co = 1 μF ceramic
Time scale: 0.2 ms/div.
Fig. 3.3V.10: Output voltage response to load current step-change
(10 A – 20 A – 10 A) at Vin = 48 V. Top trace: output voltage (100
mV/div.). Bottom trace: load current (10 A/div.). Current slew rate: 5
A/μs. Co = 470 μF POS + 1 μF ceramic. Time scale: 0.2 ms/div.
Fig. 3.3V.11: Output voltage ripple (20 mV/div.) at full rated
load current into a resistive load with Co = 10 μF tantalum + 1
μF ceramic and Vin = 48 V. Time scale: 1 μs/div..
Fig. 3.3V.12: Test setup for measuring input reflected ripple
currents, ic and is
Fig. 3.3V.13: Input reflected-ripple current, c (50 mA/div.),
measured at input terminals at full rated load current and Vin =
48 V. Refer to Fig. 3.3V.12 for test setup. Time scale: 1 μs/div.
Fig. 3.3V.14: Input reflected-ripple current, s (10 mA/div.),
measured through 10 μH at the source at full rated load current
and Vin = 48 V. Refer to Fig. 3.3V.12 for test setup. Time scale:
1 μs/div
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Fig. 3.3V.15: Output voltage vs. load current showing current
limit point and converter shutdown point. Input voltage has
almost no effect on current limit characteristic.
Fig. 3.3V.16: Load current (top trace, 20 A/div.,
50 ms/div.) into a 10 mΩ short circuit during restart, at
Vin = 48 V. Bottom trace (20 A/div., 1 ms/div.) is an expansion
of the on-time portion of the top trace.
Fig. 2.5V.1: Available load current vs. ambient air temperature
and airflow rates for SQE48T30025 converter mounted vertically
with air flowing from pin 3 to pin 1, MOSFET temperature ≤ 120
Fig. 2.5V.2: Available load current vs. ambient air temperature
and airflow rates for SQE48T30025 converter mounted
horizontally with air flowing from pin 3 to pin 1, MOSFET
° C, Vin = 48 V.
temperature ≤ 120 ° C, Vin = 48 V.
Note: NC – Natural convection
Fig. 2.5V.3: Efficiency vs. load current and input voltage for
SQE48T30025 converter mounted vertically with air flowing from
pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s) and Ta = 25 ° C.
Fig. 2.5V.4: Efficiency vs. load current and ambient temperature
for SQE48T30025 converter mounted vertically with Vin = 48 V
pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s) and Ta = 25 ° C.
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Fig. 2.5V.5: Power dissipation vs. load current and input voltage
for SQE48T30025 converter mounted vertically with air flowing
from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s) and Ta = 25° C.
Fig. 2.5V.7: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V, triggered via
ON/OFF pin. Top trace: ON/OFF signal (5 V/div.). Bottom trace:
Output voltage (1 V/div.). Time scale: 2 ms/div.
Fig. 2.5V.9: Output voltage response to load current stepchange (10 A – 20 A – 10 A) at Vin = 48 V. Top trace: output
voltage (100 mV/div.). Bottom trace: load current
(10 A/div.). Current slew rate: 0.1 A/μs. Co = 1 μF ceramic.
Time scale: 0.2 ms/div.
Fig. 2.5V.6: Power dissipation vs. load current and ambient
temperature for SQE48T30025 converter mounted vertically
with Vin = 48 V and air flowing from pin 3 to pin 1 at a rate of
200 LFM (1.0 m/s).
Fig. 2.5V.8: Turn-on transient at full rated load current
(resistive) plus 10,000 μF at Vin = 48 V, triggered via ON/OFF
pin. Top trace: ON/OFF signal (5 V/div.). Bottom trace: Output
voltage (1 V/div.). Time scale: 2 ms/div.
Fig. 2.5V.10: Output voltage response to load current stepchange (10 A – 20 A – 10 A) at Vin = 48 V. Top trace: output
voltage (100 mV/div.). Bottom trace: load current (10 A/div.).
Current slew rate: 5A/μs.Co = 470 μF POS + 1 μF ceramic.
Time scale: 0.2 ms/div.
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Fig. 2.5V.11: Output voltage ripple (20 mV/div.) at full rated
load current into a resistive load with Co = 10 μF tantalum + 1
μF ceramic and Vin = 48 V. Time scale: 1 μs/div.
Fig. 2.5V.12: Test setup for measuring input reflected ripple
currents, ic and is.
Fig. 2.5V.13: Input reflected-ripple current, c (100 mA/div.),
measured at input terminals at full rated load current and Vin =
48 V. Refer to Fig. 2.5V.12 for test setup. Time scale: 1 μs/div.
1μs/div.
Fig. 2.5V.14: Input reflected-ripple current, s (10 mA/div.),
measured through 10 μH at the source at full rated load current
and Vin = 48 V. Refer to Fig. 2.5V.12 for test setup. Time scale:
Fig. 2.5V.15: Output voltage vs. load current showing current
limit point and converter shutdown point. Input voltage has
almost no effect on current limit characteristic.
Fig. 2.5V.16: Load current (top trace, 20 A/div.,
50 ms/div.) into a 10 mΩ short circuit during restart, at
Vin = 48 V. Bottom trace (20 A/div., 2 ms/div.) is an expansion
of the on-time portion of the top trace.
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Fig. 1.8V.1: Available load current vs. ambient air temperature
and airflow rates for SQE48T30018 converter mounted vertically
with air flowing from pin 3 to pin 1, MOSFET temperature ≤ 120
Fig. 1.8V.2: Available load current vs. ambient air temperature
and airflow rates for SQE48T30018 converter mounted
horizontally with air flowing from pin 3 to pin 1, MOSFET
° C, Vin = 48 V.
temperature ≤ 120 ° C, Vin = 48 V.
Note: NC – Natural convection
Fig. 1.8V.3: Efficiency vs. load current and input voltage for
SQE48T30018 converter mounted vertically with air flowing from
pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s) and Ta = 25 ° C.
Fig. 1.8V.4: Efficiency vs. load current and ambient temperature
for SQE48T30018 converter mounted vertically with Vin = 48 V
and air flowing from pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s).
Fig. 1.8V.5: Power dissipation vs. load current and input voltage
for SQE48T30018 converter mounted vertically with air flowing
from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s) and Ta = 25 ° C.
Fig. 1.8V.6: Power dissipation vs. load current and ambient
temperature for SQE48T30018 converter mounted vertically with Vin
= 48 V and air flowing from pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s)
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Fig. 1.8V.7: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V, triggered via
ON/OFF pin. Top trace: ON/OFF signal (5 V/div.). Bottom trace:
Output voltage (1 V/div.). Time scale: 2 ms/div.
Fig. 1.8V.9: Output voltage response to load current stepchange (10 A – 20 A – 10 A) at Vin = 48 V. Top trace: output
voltage (100 mV/div.). Bottom trace: load current
(10 A/div.). Current slew rate: 0.1 A/μs. Co = 1 μF ceramic.
Time scale: 0.2 ms/div.
Fig. 1.8V.11: Output voltage ripple (20 mV/div.) at full rated
load current into a resistive load with Co = 10 μF tantalum + 1
μF ceramic and Vin = 48 V. Time scale: 1 μs/div.
Fig. 1.8V.8: Turn-on transient at full rated load current
(resistive) plus 10,000 μF at Vin = 48 V, triggered via ON/OFF
pin. Top trace: ON/OFF signal (5 V/div.). Bottom trace: Output
voltage (1 V/div.). Time scale: 2 ms/div.
Fig. 1.8V.10: Output voltage response to load current stepchange (10 A – 20 A – 10 A) at Vin = 48 V. Top trace: output
voltage (100 mV/div.). Bottom trace: load current (10 A/div.).
Current slew rate: 5 A/μs. Co = 470 μF POS + 1 μF ceramic.
Time scale: 0.2 ms/div.
Fig. 1.8V.12: Test setup for measuring input reflected ripple
currents, ic and is
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Fig. 1.8V.13: Input reflected-ripple current, c (100 mA/div.),
measured at input terminals at full rated load current and Vin =
48 V. Refer to Fig. 1.8V.12 for test setup. Time scale: 1 μs/div.
Fig. 1.8V.15: Output voltage vs. load current showing current
limit point and converter shutdown point. Input voltage has
almost no effect on current limit characteristic.
Fig. 1.8V.14: Input reflected-ripple current, s (10 mA/div.),
measured through 10 μH at the source at full rated load current
and Vin = 48 V. Refer to Fig. 1.8V.12 for test setup. Time scale: 1 μs/div
Fig. 1.8V.16: Load current (top trace, 20 A/div.,
50 ms/div.) into a 10 mΩ short circuit during restart, at
Vin = 48 V. Bottom trace (20 A/div., 2 ms/div.) is an expansion
of the on-time portion of the top trace.
Fig. 1.5V.1: Available load current vs. ambient air temperature
and airflow rates for SQE48T30015 converter mounted vertically
with air flowing from pin 3 to pin 1, MOSFET temperature ≤ 120
Fig. 1.5V.2: Available load current vs. ambient air temperature
and airflow rates for SQE48T30015 converter mounted
horizontally with air flowing from pin 3 to pin 1, MOSFET
° C, Vin = 48 V.
temperature ≤ 120 ° C, Vin = 48 V.
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Note: NC – Natural convection
Fig. 1.5V.3: Efficiency vs. load current and input voltage for
SQE48T30015 converter mounted vertically with air flowing from
pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s) and Ta = 25 ° C.
Fig. 1.5V.5: Power dissipation vs. load current and input voltage
for SQE48T30015 converter mounted vertically with air flowing
from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s) and Ta = 25 ° C.
Fig. 1.5V.7: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V, triggered via
ON/OFF pin. Top trace: ON/OFF signal (5 V/div.). Bottom trace:
Output voltage (1 V/div.). Time scale: 2 ms/div.
Fig. 1.5V.4: Efficiency vs. load current and ambient temperature
for SQE48T30015 converter mounted vertically with Vin = 48 V
and air flowing from pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s).
Fig. 1.5V.6: Power dissipation vs. load current and ambient
temperature for SQE48T30015 converter mounted vertically with
Vin = 48 V and air flowing from pin 3 to pin 1 at a rate of 200 LFM
(1.0 m/s)
Fig. 1.5V.8: Turn-on transient at full rated load current
(resistive) plus 10,000 μF at Vin = 48 V, triggered via ON/OFF
pin. Top trace: ON/OFF signal (5 V/div.). Bottom trace: Output
voltage (1 V/div.). Time scale: 2 ms/div.
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Fig. 1.5V.9: Output voltage response to load current stepchange (10 A – 20 A – 10 A) at Vin = 48 V. Top trace: output
voltage (100 mV/div.). Bottom trace: load current
(10 A/div.). Current slew rate: 0.1 A/μs. Co = 1 μF ceramic.
Time scale: 0.2 ms/div.
Fig. 1.5V.11: Output voltage ripple (20 mV/div.) at full rated
load current into a resistive load with Co = 10 μF tantalum + 1
μF ceramic and Vin = 48 V. Time scale: 1 μs/div.
Fig. 1.5V.13: Input reflected ripple-current, c (100 mA/div.),
measured at input terminals at full rated load current and Vin =
48 V. Refer to Fig. 1.5V.12 for test setup. Time scale: 1 μs/div.
Fig. 1.5V.10: Output voltage response to load current stepchange (10 A – 20 A – 10 A) at Vin = 48 V. Top trace: output
voltage (100 mV/div.). Bottom trace: load current (10 A/div.).
Current slew rate: 5A/μs. Co = 470 μF POS + 1 μF ceramic.
Time scale: 0.2 ms/div.
Fig. 1.5V.12: Test setup for measuring input reflected ripple
currents, ic and is
Fig. 1.5V.14: Input reflected-ripple current, s (10 mA/div.),
measured through 10 μH at the source at full rated load current
and Vin = 48 V. Refer to Fig. 1.5V.12 for test setup. Time scale: 1
μs/div
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Fig. 1.5V.15: Output voltage vs. load current showing current
limit point and converter shutdown point. Input voltage has
almost no effect on current limit characteristic.
Fig. 1.5V.16: Load current (top trace, 20 A/div.,
50 ms/div.) into a 10 mΩ short circuit during restart, at
Vin = 48 V. Bottom trace (20 A/div., 2 ms/div.) is an expansion
of the on-time portion of the top trace.
Fig. 1.2V.1: Available load current vs. ambient air temperature
and airflow rates for SQE48T30012 converter mounted vertically
with air flowing from pin 3 to pin 1, MOSFET temperature ≤ 120
Fig. 1.2V.2: Available load current vs. ambient air temperature
and airflow rates for SQE48T30012 converter mounted
horizontally with air flowing from pin 3 to pin 1, MOSFET
° C, Vin = 48 V.
temperature ≤ 120 ° C, Vin = 48 V.
Note: NC – Natural convection
Fig. 1.2V.3: Efficiency vs. load current and input voltage for
SQE48T30012 converter mounted vertically with air flowing from
pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s) and Ta = 25 ° C.
Fig. 1.2V.4: Efficiency vs. load current and ambient temperature
for SQE48T30012 converter mounted vertically with Vin = 48 V
and air flowing from pin 3 to pin 1 at a rate of 200 LFM (1.0 m/s).
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Fig. 1.2V.5: Power dissipation vs. load current and input voltage
for SQE48T30012 converter mounted vertically with air flowing
from pin 3 to pin 1 at a rate of 300 LFM (1.5 m/s) and Ta = 25° C.
Fig. 1.2V.7: Turn-on transient at full rated load current
(resistive) with no output capacitor at Vin = 48 V, triggered via
ON/OFF pin. Top trace: ON/OFF signal (5 V/div.). Bottom trace:
Output voltage (1 V/div.). Time scale: 2 ms/div.
Fig. 1.2V.9: Output voltage response to load current stepchange (10 A – 20 A – 10 A) at Vin = 48 V. Top trace: output
voltage (100 mV/div.). Bottom trace: load current
(10 A/div.). Current slew rate: 0.1 A/μs. Co = 1 μF ceramic.
Time scale: 0.2 ms/div.
Fig. 1.2V.6: Power dissipation vs. load current and ambient
temperature for SQE48T30012 converter mounted vertically
with Vin = 48 V and air flowing from pin 3 to pin 1 at a rate of
200 LFM (1.0 m/s).
Fig. 1.2V.8: Turn-on transient at full rated load current
(resistive) plus 10,000 μF at Vin = 48 V, triggered via ON/OFF
pin. Top trace: ON/OFF signal (5 V/div.). Bottom trace: Output
voltage (1 V/div.). Time scale: 2 ms/div.
Fig. 1.2V.10: Output voltage response to load current stepchange (10 A – 20 A – 10 A) at Vin = 48 V. Top trace: output
voltage (100 mV/div.). Bottom trace: load current (10 A/div.).
(10 A/div.). Current slew rate: 0.1 A/μs. Co = 1 μF ceramic.
Time scale: 0.2 ms/div.
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Fig. 1.2V.11: Output voltage ripple (20 mV/div.) at full rated
load current into a resistive load with Co = 10 μF tantalum + 1
μF ceramic and Vin = 48 V. Time scale: 1 μs/div.
Fig. 1.2V.13: Input reflected ripple-current, c (100 mA/div.),
measured at input terminals at full rated load current and Vin =
48 V. Refer to Fig. 1.2V.12 for test setup. Time scale: 1 μs/div.
Fig. 1.2V.15: Output voltage vs. load current showing current
limit point and converter shutdown point. Input voltage has
almost no effect on current limit characteristic.
Fig. 1.2V.11: Output voltage ripple (20 mV/div.) at full rated
currents, ic and is
Fig. 1.2V.14: Input reflected-ripple current, s (10 mA/div.),
measured through 10 μH at the source at full rated load current
and Vin = 48 V. Refer to Fig. 1.2V.12 for test setup. Time scale:
1 μs/div.
Fig. 1.2V.16: Load current (top trace, 20 A/div., 50 ms/div.) into
a 10 mΩ short circuit during restart, at Vin = 48 V. Bottom trace
(20 A/div., 5 ms/div.) is an expansion of the on-time portion of
the top trace.
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HT
(Max. Height)
CL
(Min. Clearance)
D
+0.000 [+0.00]
-0.038 [- 0.97]
0.374 [9.5]
+0.016 [+0.41]
-0.000 [- 0.00]
0.035 [0.89]
G
0.407 [10.34]
0.035 [0.89]
Height
Option
PL
Pin Length
Pin Option
± 0.005 [± 0.13]
A
0.188 [4.78]
B
0.145 [3.68]
C
0.110 [2.79]
Pad/Pin Connections
Pad/Pin #
Function
1
Vin (+)
2
ON/OFF
3
Vin (-)
4
Vout (-)
5
SENSE(-)
6
TRIM
7
SENSE(+)
8
Vout (+)
SQE48T Platform Notes
All dimensions are in inches [mm]
Pins 1-3 and 5-7 are Ø 0.040” [1.02] with Ø 0.078” [1.98] shoulder
Pins 4 and 8 are Ø 0.062” [1.57]
without shoulder
Pin Material & Finish: Brass Alloy 360 with Matte Tin over Nickel
Converter Weight: 0.72 oz [20.6 g]
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Product
Input
Series1 Voltage
SQE
48
Mounting
Scheme
Rated
Load
Current
Output
Voltage
T
30
033
-
ON/OFF
Logic
Maximum
Height [HT]
Pin Length
[PL]
N
G
B
Special Features
0
0 ⇒ STD
OneEighth
Brick
Format
36-75 V
T
Throughhole
30 ADC
012 ⇒ 1.2 V
015 ⇒ 1.5 V
018 ⇒ 1.8 V
025 ⇒ 2.5 V
033 ⇒ 3.3 V
N
Negative
P
Positive
D2⇒ 0.374”
G ⇒ 0.407”
A ⇒ 0.188”
B ⇒ 0.145”
C ⇒ 0.110”
RoHS
L⇒
Latching Option
T⇒
Alternative Trim
Option
(1.2 V only)
No Suffix
RoHS
lead-solderexemption
compliant
G RoHS
compliant for all
six substances
The example above describes p/n SQE48T30033-NGB0: 36-75V input, through-hole, 30A @ 3.3 V output, negative ON/OFF
logic, a 0.145” pin length, maximum height of 0.407”, standard (non-latching) protection, and RoHS lead-solder-exemption
compliance.
1All
possible option combinations are not necessarily available for every model. Contact Customer Service to confirm availability.
Height option D is only available on model SQE48T30033-NDA0.
2Maximum
NUCLEAR AND MEDICAL APPLICATIONS - Products are not designed or intended for use as critical components in life support systems, equipment used in
hazardous environments, or nuclear control systems.
TECHNICAL REVISIONS - The appearance of products, including safety agency certifications pictured on labels, may change depending on the date
manufactured. Specifications are subject to change without notice.
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BCD.00638_AA