Features
Figure 1. Simplifi ed Schematic
■
■
■
■
■
■
■
■
■
■
■
■
■
Standard quarter-brick package/pinout
in through-hole or SMT version
Low cost; Low profi le, 0.35" (8.9mm)
24V and 48V nominal inputs
Output current: 8 to 25 Amps
Output voltages: 1.2/1.5/1.8/2/2.5/3.3/5/12V
Interleaved synchronous-rectifi er topology
· Ultra high effi ciency
· No output reverse conduction
Outstanding thermal performance
On/off control, trim & sense functions
Fully isolated, 2250Vdc (BASIC)
Output overvoltage protection
Fully I/O protected; Thermal shutdown
UL/EN/IEC60950 safety approvals
Qual/HALT/EMI tested
–VIN
(1)
+VIN
(3)
OPTO
ISOLATION
PWM
CONTROLLER
REFERENCE &
ERROR AMP
INPUT UNDERVOLTAGE, INPUT
OVERVOLTAGE, AND OUTPUT
OVERVOLTAGE COMPARATORS * Can be ordered with positive (standard) or negative (optional) polarity.
REMOTE
ON/OFF
CONTROL*
(2)
+SENSE
(7)
–SENSE
(5)
+VOUT
(8)
VOUT
TRIM
(6)
–VOUT
(4)
SWITCH
CONTROL
For applications requiring improved electrical and thermal perfomance at reduced cost DATEL's
new ULQ Series "Quarter-Brick" DC/DC Converters suit perfectly. They measure just 1.45 x 2.30 x
0.35 inches (36.8 x 58.4 x 8.9mm) and fi t the industry-standard footprint. You can also "pick-and-
place" the ULQ-SMT version optimizing your automated SMT process.
From an 18-36V or 36-75V input, ULQ's deliver outputs of 1.2, 1.5, 1.8, or 2V fully rated at 15 or
25A, 2.5 or 3.3V at 15 or 20A, 5V at 15A and 12V at 8-10A. They
employ an interleaved, synchronous-rectifi er topology that exploits 100% of their duty cycle. They
simultaneously achieve ultra-high effi ciency (to 91%), tight line/load regulation (±0.125/0.25%), low
noise (25-70mVp-p), and quick step response (200μsec).
A state of the art, single-board, open-frame design with reduced component count, high
effi ciency, low-on-resistance FET's, and planar magnetics embedded in heavy-copper pc boards all
contribute to impressive thermal derating.
The ULQ's feature set includes high isolation (2250Vdc), input pi fi lters, input undervoltage shut-
down, output overvoltage protection, current limiting, short-circuit protection and thermal shutdown.
The standard footprint carries on/off control (positive or negative polarity), output trim (+10/–20%)
and output sense functions.
All ULQ quarter-bricks are designed to meet the BASIC-insulation requirements of UL/EN/
IEC60950 and they will carry the CE mark. Safety certifi cations, EMC compliance testing and qualifi -
cation testing (including HALT) are currently in progress. Contact DATEL for latest updates.
Typical topology is shown
Typical topology is shown.
Typical units
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
For full details go to
www.murata-ps.com/rohs
www.murata-ps.com
www.murata-ps.com
email: sales@murata-ps.com
21 Feb 2011 MDC_ULQ-15A.B03 Page 1 of 16
➀ Typical at TA = +25°C under nominal line voltage and full-load conditions. All models are
specifi ed with an external 1μF multi-layer ceramic and 10μF capacitors across their output pins.
➁ Ripple/Noise (R/N) measured over a 20MHz bandwidth.
➂ Devices have no minimum-load requirements and will regulate under no-load conditions.
Regulation specifi cations describe the output voltage deviation as the line voltage or load is
varied from its nominal/midpoint value to either extreme. (Load step = 50%.)
➃ Nominal line voltage, no load/full load condition.
➄ Please refer to the Part Number Structure when ordering.
➅ Not all model number combinations are available. Consult Murata Power Solutions.
MECHANICAL SPECIFICATIONS
0.300
(7.6)
1.35 (34.3)
0.600 (15.2)
4 EQ. SP.
@ 0.150 (3.81)
0.600
(15.2)
2.00 (50.8)
BOTTOM VIEW
1
2
3 8
7
6
5
4
A
A
B
B
B
2.22 (56.4)
0.375 MAX.
(9.53)
0.150
(3.81)
0.125 MIN.
(3.2)
PINS 1-3, 5-7:
0.040 ±0.001
(1.016 ±0.025)
PINS 4, 8:
0.062 ±0.001
(1.575 ±0.025)
PLASTIC STANDOFFS
ARE RELIEVED 0.030 (0.76)
IN SOLDER JOINT AREA
Case C40
Surface-mount Package
See page 16 for the
recommneded pad
layout dimensions.
Case C37, Through-Hole Package
PART NUMBER STRUCTURE
Nominal Output Voltage
3.3
LQ 20-/D48
Input Voltage Range
Maximum Rated Output
-N
Surface-Mount Package
(see list above)
M
U
Quarter-Brick Package
Remote On/Off Control Polarity
Output
Confi guration
Lx
Pin Length Option
See page 16 for complete Part Number Structure.
RoHS-6 compliant
C
-
Third Angle Projection
Dimensions are in inches (mm) shown for ref. only.
Components are shown for reference only.
Tolerances (unless otherwise specified):
.XX ± 0.02 (0.5)
.XXX ± 0.010 (0.25)
Angles ± 2˚
0.300
(7.6)
1.45 (36.8)
0.600 (15.2)
4 EQ. SP. @ 0.150 (3.81)
0.110
(2.79)
0.125
(3.2)
0.600
(15.2)
B
B
B
A
2.30 (58.4)
OVERALL DIMENSIONS :
2.30 (58.4) x 1.45 (36.8) x 0.70 (17.8)
BEFORE REMOVAL OF PROTECTIVE
HEAT SHIELD
PROTECTIVE
HEAT SHIELD
0.35
(8.9)
BOTTOM VIEW
1
2
38
7
6
5
4
ORDERING GUIDE
Root Model ➄
Output Input Effi ciency Package
(Case,
Pinout)
VOUT
(Volts)
IOUT ➁
(Amps)
R/N (mVp-p) ➁Regulation (Max.) VIN Nom.
(Volts)
Range
(Volts)
IIN ➃
(mA/A)
Typ. Max. Line Load ➂Min. Typ.
ULQ-1.5/15-D48N-C 1.5 15 25 50 ±0.125% ±0.25% 48 36-75 35/0.5 87% 89% C37, P32
ULQ-1.5/25-D24P-C 1.5 25 50 100 ±0.125% ±0.25% 24 18-36 50/1.8 85.5% 87.5% C37, P32
ULQ-1.5/25-D48N-C 1.5 25 45 75 ±0.125% ±0.25% 48 36-75 30/0.9 85% 87% C37, P32
ULQ-1.8/15-D48N-C 1.8 15 25 50 ±0.125% ±0.25% 48 36-75 35/0.6 87.5% 89% C37, P32
ULQ-1.8/25-D24P-C 1.8 25 50 100 ±0.125% ±0.25% 24 18-36 90/2.2 85.5% 87.5% C37, P32
ULQ-1.8/25-D48N-C 1.8 25 70 100 ±0.25% ±0.25% 48 36-75 45/1.1 85.5% 87.5% C37, P32
ULQ-2/15-D48N-C 2 15 25 50 ±0.125% ±0.25% 48 36-75 45/0.6 87% 89% C37, P32
ULQ-2/25-D24P-C 2 25 50 100 ±0.125% ±0.25% 24 18-36 50/2.4 86% 88% C37, P32
ULQ-2/25-D48N-C 2 25 70 100 ±0.25% ±0.25% 48 36-75 50/1.2 86% 88% C37, P32
ULQ-2.5/15-D48N-C 2.5 15 35 55 ±0.125% ±0.25% 48 36-75 45/0.9 88% 89.5% C37/C40, P32
ULQ-3.3/15-D48N-C 3.3 15 45 75 ±0.125% ±0.25% 48 36-75 45/1.2 88.5% 90.5% C37/C40, P32
ULQ-3.3/20-D24P-C 3.3 20 50 100 ±0.125% ±0.25% 24 18-36 80/3.1 87.5% 89.5% C37/C40, P32
ULQ-3.3/20-D48N-C 3.3 20 45 75 ±0.125% ±0.25% 48 36-75 45/1.6 88% 90% C37/C40, P32
ULQ-5/15-D24P-C 5 15 50 100 ±0.25% ±0.25% 24 18-36 50/3.5 89% 91% C37/C40, P32
ULQ-5/15-D48N-C 5 15 50 100 ±0.1% ±0.4% 48 36-75 50/1.7 89% 91% C37/C40, P32
ULQ-12/8-D24P-C 12 8 95 130 ±0.25% ±0.25% 24 18-36 90/4.4 89% 90.5% C37/C40, P32
ULQ-12/10-D48N-C 12 10 90 130 ±0.25% ±0.25% 48 36-75 80/2.9 88% 90% C37/C40, P32
Performance Specifi cations and Ordering Guide ➀
* These converters are pin-for-pin/plug-compatible to competitive
units. Other units may use different pin numbering or alternate
outline views. When laying out your PC board, follow the pin
FUNCTION. DOSA designates Pin 1 as +Input and Pin 3 as -Input.
** The Remote On/Off can be provided with either positive ("P" suffi x)
or negative ("N" suffi x) polarity.
DOSA-Compatible I/O Connections
Pin Function P32 Pin Function P32
1–Input* 5–Sense
2Remote On/Off** 6Output Trim
3+Input* 7+Sense
4–Output 8+Output
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
www.murata-ps.com email: sales@murata-ps.com
21 Feb 2011 MDC_ULQ-15A.B03 Page 2 of 16
Performance/Functional Specifi cations
Typical @ TA = +25°C under nominal line voltage, full-load conditions, unless noted. (1)
Absolute Maximum Ratings
Input Voltage: D24V Models D48V Models
Continuous: See OVP 81 Volts
Transient (100msec): NA 100 Volts
Input Reverse-Polarity Protection Input Current must be <5A. 1 minute
duration. Fusing recommended.
Output Current Current limited. Devices can withstand
an indefi nite output short circuit.
On/Off Control (Pin 2) Max. Voltages
Referenced to –Input (pin 1) –0.3 to +13.6 Volts
Storage Temperature –55 to +125°C
Lead Temperature
Through-hole Soldering +300°C, 10 seconds
SMT Soldering Refer to solder profi le
These are stress ratings. Exposure of devices to any of these conditions may adversely
affect long-term reliability. Proper operation under conditions other than those listed in the
Performance/Functional Specifi cations Table is not implied, nor recommended.
Environmental
Calculated MTBF: (13) TBD million hours
Operating Temperature (Ambient): (4) (14) –40 to +85°C with derating
See derating curves
PCB Temperature: (4) (7)
Maximum Allowable +100°C
Thermal Shutdown +105 to 120°C, +115°C typical
Physical
Dimensions See Mechanical Dimensions
Pin Material (through-hole) Gold-plated copper alloy with nickel
underplate
Pad Material (SMT) Copper alloy, pure tin over nickel underplate
Weight: 1 ounce (28 grams)
Primary-to-Secondary Insulation Level Basic
EMI Conducted and Radiated FCC Part 15, EN55022 may require
external fi lter
Safety UL/IEC/EN60950-1 CSA-C22.2 No. 234
(1) All models are tested and specifi ed with external output capacitors (1μF ceramic in parallel
with 10μF tantalum), unless otherwise noted. These converters have no minimum-load require-
ments and will effectively regulate under no-load conditions.
(2) Contact Murata Power Solutions for input voltage ranges other than those listed.
(3) See Absolute Maximum Ratings for allowable input voltages.
(4) See Technical Notes/Performance Curves for additional explanations and details.
(5) Input Ripple Current is tested/specifi ed over a 5-20MHz bandwidth with an external 33μF input
capacitor and a simulated source impedance of 220μF and 12μH. See I/O Filtering, Input
Ripple Current and Output Noise for details.
(6) The On/Off Control is designed to be driven with open-collector (or equivalent) logic or the
application of appropriate voltages (referenced to –Input (pin 1)). See Remote On/Off Control
for more details.
(7) All models are fully operational and meet published specifi cations, including "cold start," at –40°C.
(8) Extreme Accuracy refers to the accuracy of either trimmed or untrimmed output voltages over
all normal operating ranges and combinations of input voltage, output load and temperature.
(9) See Output Trimming for detailed trim equations.
(10) The Current-Limit Inception point is the output current level at which the ULQ’s power-limiting
circuitry drops the output voltage 2% from its initial value. See Output Current Limiting and
Short-Circuit Protection for more details.
(11) See Performance Curves for additional information.
(12) For the Start-Up Time specifi cations, output settling is defi ned by the output voltage having
reached ±1% of its fi nal value.
(13) MTBF’s are calculated using Telcordia (Bellcore) Method 1 Case 3, ground fi xed conditions,
+40°C case temperature, and full-load conditions.
Input
Input Voltage Range: (2)
D24 Models 18-36 Volts (24V nominal)
D48 Models 36-75 Volts (48V nominal)
Overvoltage Shutdown
D24 Models 37-41 Volts (39V typical)
D48 Models None
(3)
Start-Up Threshold: (4)
D24 Models 16-18 Volts (17.5V typical)
D48 Models 34-36 Volts (35V typical)
Undervoltage Shutdown: (4)
D24 Models 15.5-17.5 Volts (16.75V typical)
D48 Models 32.5-34.5 Volts (33.5V typical)
Input Current:
Normal Operating Conditions See Ordering Guide
Inrush Transient 0.05A2sec maximum
Short Circuit 50-100mA
Standby Mode:
Off, UV, Thermal Shutdown 4-10mA
Input Refl ected Ripple Current (5) 8-50mAp-p
Internal Input Filter Type Pi
Reverse-Polarity Protection (3) 1 minute duration, 5A maximum
Remote On/Off Control (Pin 2): (6)
Positive Logic ("P" Suffi x Models) On = open, open collector or
3.5-13V applied
Off = pulled low to 0-0.8V IIN = 6mA max.
Negative Logic ("N" Suffi x Models) On = pulled low to 0-0.8V IIN = 6mA max.
Off = open, open collector or
3.5-13V applied
Output
Minimum Loading No load
VOUT Accuracy (Full Load):
Initial ±1.25% maximum
Temperature Coeffi cient ±0.02% per °C
Extreme
(8) ±3%
VOUT Trim Range (9) +10%, –20%
Remote Sense Compensation (4) +10%
Ripple/Noise (20MHz BW) See Ordering Guide
Line/Load Regulation See Ordering Guide
Effi ciency See Ordering Guide
Isolation Voltage: Input-to-Output 2000Vdc minimum, D24 models
2250Vdc minimum, D48 models
Isolation Resistance 100MΩ
Isolation Capacitance 470pF
Current Limit Inception (98% VOUT) (10)
After warmup +125% of maximum rated current
Short Circuit: (4)
Current Hiccup with auto-restart
Duration Continuous
Overvoltage Protection: (4) VOUT nominal +20%
OVP method Comparator magnetic feedback
Dynamic Characteristics
Dynamic Load Response (11)
(50% Load Step) 60-300μsec, model dependent
Start-Up Time: (4) (12)
V
IN to VOUT; On/Off to VOUT 30msec typical, 50msec maximum
Switching Frequency 160-300kHz, model dependent
Maximum Capacitive Load 4700 to 10,000μF, model dependent
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
www.murata-ps.com email: sales@murata-ps.com
21 Feb 2011 MDC_ULQ-15A.B03 Page 3 of 16
Input Fusing
Certain applications and/or safety agencies may require the installation of
fuses at the inputs of power conversion components. Fuses should also be
used if the possibility of sustained, non-current-limited, input-voltage polarity
reversals exists. For DATEL ULQ series DC/DC converters, we recommend
the use of a time delay fuse, installed in the ungrounded input supply line,
with a value no greater than 20 Amps.
As a rule of thumb however, we recommend the use of a normal-blow or
slow-blow fuse with a typical value about twice the maximum input current,
calculated at low line with the converter's minimum effi ciency.
All relevant national and international safety standards and regulations must
be observed by the installer. For system safety agency approvals, the
converters must be installed in compliance with the requirements of the end-
use safety standard, i.e. IEC/EN/UL60950.
Input Reverse-Polarity Protection
If the input voltage polarity is accidentally reversed, an internal diode will
become forward biased and likely draw excessive current from the power
source. If this source is not current limited or the circuit appropiately fused, it
could cause permanent damage to the converter.
Input Undervoltage Shutdown and Start-Up Threshold
Under normal start-up conditions, devices will not begin to regulate properly
until the ramping-up input voltage exceeds the Start-Up Threshold Voltage.
Once operating, devices will not turn off until the input voltage drops below
the Undervoltage Shutdown limit. Subsequent re-start will not occur until the
input is brought back up to the Start-Up Threshold. This built in hysteresis
prevents any unstable on/off situations from occurring at a single input
voltage.
Start-Up Time
The VIN to VOUT Start-Up Time is the time interval between the point at which
the ramping input voltage crosses the Start-Up Threshold and the fully loaded
output voltage enters and remains within its specifi ed accuracy band. Actual
measured times will vary with input source impedance, external input capaci-
tance, and the slew rate and fi nal value of the input voltage as it appears at
the converter. The ULQ Series implements a soft start circuit to limit the duty
cycle of its PWM controller at power up, thereby limiting the input inrush current.
The On/Off Control to VOUT start-up time assumes the converter has its
nominal input voltage applied but is turned off via the On/Off Control pin. The
specifi cation defi nes the interval between the point at which the converter is
turned on (released) and the fully loaded output voltage enters and remains
within its specifi ed accuracy band.
Similar to the VIN to VOUT start-up, the On/Off Control to VOUT start-up
time is also governed by the internal soft start circuitry and external load
capacitance. The difference in start up time from VIN to VOUT and from On/Off
Control to VOUT is therefore insignifi cant.
Input Overvoltage Shutdown
All 24VIN ULQ DC/DC's are equipped with input overvoltage protection. Input
voltages exceeding the input overvoltage shutdown specifi cation listed in the
Performance/Functional Specifi cations will cause the device to shutdown.
A built-in hysterisis for all models will not allow the converter to restart until
the input voltage is suffi ciently reduced.
All 48VIN models have the overvoltage shutdown function disabled, based
on requirements to withstand brief input surges and transients to 100V for
up to 100msec without voltage interruption. Contact DATEL to have input
overvoltage shutdown for 48VIN models enabled.
Input Source Impedance
The input of ULQ converters must be driven from a low ac-impedance
source. The DC/DC's performance and stability can be compromised by
the use of highly inductive source impedances. The input circuit shown in
Figure 2 is a practical solution that can be used to minimize the effects of
inductance in the input traces. For optimum performance, components should
be mounted close to the DC/DC converter.
I/O Filtering, Input Ripple Current, and Output Noise
All models in the ULQ Series are tested/specifi ed for input refl ected
ripple current and output noise using the specifi ed external input/output
components/circuits and layout as shown in the following two fi gures. External
input capacitors (CIN in Figure 2) serve primarily as energy-storage elements,
minimizing line voltage variations caused by transient IR drops in conductors
from backplane to the DC/DC. Input caps should be selected for bulk capaci-
tance (at appropriate frequencies), low ESR, and high rms-ripple-current
ratings. The switching nature of DC/DC converters requires that dc voltage
sources have low ac impedance as highly inductive source impedance can
affect system stability. In Figure 2, CBUS and LBUS simulate a typical dc
voltage bus. Your specifi c system confi guration may necessitate additional
considerations.
TECHNICAL NOTES
In critical applications, output ripple/noise (also referred to as periodic and
random deviations or PARD) may be reduced below specifi ed limits using fi l-
tering techniques, the simplest of which is the installation of additional exter-
nal output capacitors. They function as true fi lter elements and should be
selected for bulk capacitance, low ESR and appropriate frequency response.
All external capacitors should have appropriate voltage ratings and be
located as close to the converter as possible. Temperature variations for all
relevant parameters should also be taken carefully into consideration. The
most effective combination of external I/O capacitors will be a function of
line voltage and source impedance, as well as particular load and layout
conditions. Our Applications Engineers can recommend potential solutions
and discuss the possibility of our modifying a given device's internal fi ltering
to meet your specifi c requirements. Contact our Applications Engineering
Group for additional details.
Figure 2. Measuring Input Ripple Current
C
IN
V
IN
C
BUS
L
BUS
C
IN
= 33μF, ESR < 700mΩ @ 100kHz
C
BUS
= 220μF, ESR < 100mΩ @ 100kHz
L
BUS
= 12μH
3
1
+INPUT
–INPUT
CURRENT
PROBE
TO
OSCILLOSCOPE
+
–
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
www.murata-ps.com email: sales@murata-ps.com
21 Feb 2011 MDC_ULQ-15A.B03 Page 4 of 16
In Figure 3, the two copper strips simulate real-world pcb impedances
between the power supply and its load. In order to minimize measurement
errors, scope measurements should be made using BNC connectors, or the
probe ground should be less than ½ inch and soldered directly to the fi xture.
C1
C1 = 0.1μF CERAMIC
C2 = 10μF TANTALUM
LOAD 2-3 INCHES (51-76mm) FROM MODULE
C2 R
LOAD
7
8
COPPER STRIP
4
5COPPER STRIP
SCOPE
+OUTPUT
–OUTPUT
+SENSE
–SENSE
Figure 3. Measuring Output Ripple/Noise (PARD)
Floating Outputs
Since these are isolated DC/DC converters, their outputs are "fl oating" with
respect to their input. Designers will normally use the –Output (pin 4) as the
ground/return of the load circuit. You can however, use the +Output (pin 8) as
ground/return to effectively reverse the output polarity.
Minimum Output Loading Requirements
ULQ converters employ a synchronous-rectifi er design topology and all
models regulate within spec and are stable under no-load to full load condi-
tions. Operation under no-load conditions however might slightly increase the
output ripple and noise.
Thermal Shutdown
The ULQ converters are equipped with thermal-shutdown circuitry. If envi-
ronmental conditions cause the temperature of the DC/DC converter to
rise above the designed operating temperature, a precision temperature
sensor will power down the unit. When the internal temperature decreases
below the threshold of the temperature sensor, the unit will self start. See
Performance/Functional Specifi cations.
Output Overvoltage Protection
The ULQ output voltage is monitored for an overvoltage condition using a
comparator. The signal is optically coupled to the primary side and if the
output voltage rises to a level which could be damaging to the load, the sens-
ing circuitry will power down the PWM controller causing the output voltage
to decrease. Following a time-out period the PWM will restart, causing the
output voltage to ramp to its appropriate value. If the fault condition persists,
and the output voltage again climbs to excessive levels, the overvoltage
circuitry will initiate another shutdown cycle. This on/off cycling is referred to
as "hiccup" mode.
Current Limiting
As soon as the output current increases to approximately 130% of its rated
value, the DC/DC converter will go into a current-limiting mode. In this condi-
tion, the output voltage will decrease proportionately with increases in output
current, thereby maintaining somewhat constant power dissipation. This is
commonly referred to as power limiting. Current limit inception is defi ned
as the point at which the full-power output voltage falls below the specifi ed
tolerance. See Performance/Functional Specifi cations. If the load current,
being drawn from the converter, is signifi cant enough, the unit will go into a
short circuit condition as described below.
Short Circuit Condition
When a converter is in current-limit mode, the output voltage will drop as
the output current demand increases. If the output voltage drops too low, the
magnetically coupled voltage used to develop primary side voltages will also
drop, thereby shutting down the PWM controller. Following a time-out period,
the PWM will restart causing the output voltage to begin ramping to their
appropriate value. If the short-circuit condition persists, another shutdown
cycle will be initiated. This on/off cycling is referred to as "hiccup" mode.
The hiccup cycling reduces the average output current, thereby preventing
internal temperatures from rising to excessive levels. The ULQ Series is
capable of enduring an indefi nite short circuit output condition.
LOAD
+OUTPUT
–INPUT
Sense Current
Contact and PCB resistance
losses due to IR drops
Contact and PCB resistance
losses due to IR drops
Sense Return
+INPUT
ON/OFF
CONTROL TRIM
+SENSE
–OUTPUT
–SENSE
4
5
1
3
6
8
IOUT Return
IOUT
7
2
Remote Sense
Note: The Sense and VOUT lines are internally connected through low-value
resistors. Nevertheless, if the sense function is not used for remote regulation
the user should connect the +Sense to +VOUT and -Sense to –VOUT at the
DC/DC converter pins.
ULQ series converters employ a sense feature to provide point of use regula-
tion, thereby overcoming moderate IR drops in pcb conductors or cabling.
The remote sense lines carry very little current and therefore require minimal
cross-sectional-area conductors. The sense lines, which are capacitively
coupled to their respective output lines, are used by the feedback control-loop
to regulate the output. As such, they are not low impedance points and must
be treated with care in layouts and cabling. Sense lines on a pcb should be
run adjacent to dc signals, preferably ground. In cables and discrete wiring
applications, twisted pair or other techniques should be implemented.
ULQ series converters will compensate for drops between the output voltage
at the DC/DC and the sense voltage at the DC/DC provided that:
[VOUT(+) –VOUT(–)] – [Sense(+) –Sense (–)] ≤ 10% VOUT
Figure 4. Remote Sense Circuit Confi guration
FEATURES AND OPTIONS
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
www.murata-ps.com email: sales@murata-ps.com
21 Feb 2011 MDC_ULQ-15A.B03 Page 5 of 16
UP VO – 1.5
RT (kΩ) = –10.2
6.23(VO – 1.226)
1.5 – VO
RT (kΩ) = –10.2
7.64
DOWN
UP VO – 1.8
RT (kΩ) = –10.2
7.44(VO – 1.226)
1.8 – VO
RT (kΩ) = –10.2
9.12
DOWN
UP VO – 2.5
RT (kΩ) = –10.2
10(VO – 1.226)
2.5 – VO
RT (kΩ) = –10.2
12.26
DOWN
UP VO – 3.3
RT (kΩ) = –10.2
13.3(VO – 1.226)
3.3 – VO
RT (kΩ) = –10.2
16.31
DOWN
ULQ-1.5/15-D48, ULQ-1.5/25-D24 & D48
ULQ-1.8/15-D48, ULQ-1.8/25-D24 & D48
ULQ-2.5/15-D48, ULQ-2.5/20-D24 & D48
ULQ-3.3/15-D48, ULQ-3.3/20-D24 & D48
ULQ-2/15-D48, ULQ-2/15-D24 & D48
UP VO – 1.2
RT (kΩ) = –1.413
1.308(VO – 0.793)
1.2 – VO
RT (kΩ) = –1.413
1.037
DOWN
ULQ-1.2/15-D48 & ULQ-1.2/25-D48
UP VO – 2
RT (kΩ) = –10.2
8.28(VO – 1.226)
2 – VO
RT (kΩ) = –10.2
10.15
DOWN
UP VO – 5
RT (kΩ) = –10.2
20.4(VO – 1.226)
5 – VO
RT (kΩ) = –10.2
25.01
DOWN
ULQ-5/15-D24, -D48
UP VO – 12
RT (kΩ) = –10.2
49.6(VO – 1.226)
12 – VO
RT (kΩ) = –10.2
60.45
DOWN
ULQ-12/8-D24, ULQ-12/10-D48
Output overvoltage protection is monitored at the output voltage pin, not the
Sense pin. Therefore, excessive voltage differences between VOUT and Sense
in conjunction with trim adjustment of the output voltage can cause the over-
voltage protection circuitry to activate (see Performance Specifi cations for
overvoltage limits). Power derating is based on maximum output current and
voltage at the converter's output pins. Use of trim and sense functions can
cause output voltages to increase, thereby increasing output power beyond
the conveter's specifi ed rating, or cause output voltages to climb into the
output overvoltage region. Therefore, the designer must ensure:
(VOUT at pins) × (IOUT) ≤ rated output power
Trimming Output Voltage
ULQ converters have a trim capability (pin 6) that enables users to adjust
the output voltage from +10% to –20% (refer to the trim equations and trim
graphs that follow). Adjustments to the output voltage can be accomplished
via a trim pot (Figure 5) or a single fi xed resistor as shown in Figures 6 and 7.
A single fi xed resistor can increase or decrease the output voltage depending
on its connection. Resistors should be located close to the converter and
have TCR's less than 100ppm/°C to minimize sensitivity to changes in
temperature. If the trim function is not used, leave the trim pin open.
LOAD
RTRIM DOWN
+OUTPUT
–INPUT
+INPUT
ON/OFF
CONTROL TRIM
+SENSE
–OUTPUT
–SENSE
4
5
1
3
6
8
7
2
LOAD
RTRIM UP
+OUTPUT
–INPUT
+INPUT
ON/OFF
CONTROL TRIM
+SENSE
–OUTPUT
–SENSE
4
5
1
3
6
8
7
2
Figure 5. Trim Connections Using A Trimpot
Figure 7. Trim Connections To Decrease Output Voltages Using Fixed Resistors
A single resistor connected from the Trim pin (pin 6) to the +Sense (pin 7) will
increase the output voltage. A resistor connected from the Trim Pin (pin 6) to
the –Sense (pin 5) will decrease the output voltage.
Trim adjustments greater than the specifi ed +10%/–20% can have an
adverse affect on the converter’s performance and are not recommended.
Excessive voltage differences between VOUT and Sense, in conjunction with
trim adjustment of the output voltage, can cause the overvoltage protection
circuitry to activate (see Performance Specifi cations for overvoltage limits).
Temperature/power derating is based on maximum output current and volt-
age at the converter's output pins. Use of the trim and sense functions can
cause output voltages to increase, thereby increasing output power beyond
the converter's specifi ed rating, or cause output voltages to climb into the
output overvoltage region. Therefore:
(VOUT at pins) x (IOUT) ≤ rated output power
The Trim pin (pin 6) is a relatively high impedance node that can be suscep-
tible to noise pickup when connected to long conductors in noisy environ-
ments. In such cases, a 0.22μF capacitor can be added to reduce this long
lead effect.
LOAD
+OUTPUT
–INPUT
+INPUT
ON/OFF
CONTROL TRIM
+SENSE
–OUTPUT
–SENSE
4
5
1
3
6
8
7
25-22
TURNS
Figure 6. Trim Connections To Increase Output Voltages Using Fixed Resistors
Trim Equations
Note: Resistor values are in kΩ. Adjustment accuracy is subject to resistor
tolerances and factory-adjusted output accuracy. VO = desired output voltage.
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
www.murata-ps.com email: sales@murata-ps.com
21 Feb 2011 MDC_ULQ-15A.B03 Page 6 of 16
012345678910
VOUT INCREASE (%)
RESISTANCE
1 x 107
1 x 106
1 x 105
1 x 103
1 x 104
012345678910
VOUT INCREASE (%)
RESISTANCE
1 x 107
1 x 106
1 x 105
1 x 104
012345678910
VOUT INCREASE (%)
RESISTANCE
1 x 107
1 x 106
1 x 105
1 x 104
012345678910
VOUT INCREASE (%)
RESISTANCE
1 x 107
1 x 106
1 x 105
1 x 104
Trim-Up Resistance vs. Percentage Increase in Output Voltage
Model ULQ-1.5
Model ULQ-1.8
Model ULQ-2.5
Model ULQ-3.3
0 2 4 6 8 101214161820
VOUT DECREASE (%)
RESISTANCE
1 x 107
1 x 106
1 x 105
1 x 104
012345678910
VOUT INCREASE (%)
RESISTANCE
1 x 107
1 x 106
1 x 105
1 x 104
Trim-Down Resistance vs. Percentage Decrease
in Output Voltage
Model ULQ-2
Model ULQ-1.5
Model ULQ-1.8
Model ULQ-2
Model ULQ-2.5
Model ULQ-3.3
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
www.murata-ps.com email: sales@murata-ps.com
21 Feb 2011 MDC_ULQ-15A.B03 Page 7 of 16
On/Off Control ("P" or "N" suffi x)
The input-side, remote On/Off Control function (pin 2) can be ordered to
operate with either polarity:
"P" suffi x: Standard models are equipped with Positive-polarity and these
devices are enabled when pin 2 is left open (or is pulled high, applying +3.5V
to +13 with respect to –Input, pin 1) as per Figure 8. Positive-polarity devices
are disabled when pin 2 is pulled low (0 to 0.8V with respect to –Input).
"N" suffi x: Optional Negative-polarity devices are off when pin 2 is left open
(or pulled high, applying +3.5V to +13V), and on when pin 2 is pulled low (0 to
0.8V) with respect to –Input as shown in Figure 9.
2
1
3+INPUT +VCC
–INPUT
ON/OFF
CONTROL
2
1
3+INPUT
13V CIRCUIT
5V CIRCUIT
–INPUT
ON/OFF
CONTROL
Figure 8. Driving the Positive Polarity On/Off Control Pin
Figure 9. Driving the Negative Polarity On/Off Control Pin
Surface-Mount Package ("M" suffi x)
DATEL's ULQ series SMT DC/DC converters are the only higher-power (to
66W) DC/DC's that can be automatically "pick-and-placed" using standard
vacuum-pickup equipment and subsequently refl owed using high-tempera-
ture, lead-free solder.
Virtually all SMT DC/DC's today are unprotected "open-frame" devices
assembled by their vendors with high-temperature solder (usually
Sn96.5/Ag3.5 with a melting point +221°C) so that you may attach them
to your board using low-temperature solder (usually Sn63/Pb37 with a melt-
ing point of +183°C). Conceptually straightforward, this "stepped" solder
approach has its limitations . . . and is clearly out of step with an industry
trending toward the broad use of lead-free solders. No need to experiment
and develop refl ow profi les that ensure the components on their DC/DC never
exceed 215-216°C. If those components get too hot, "double-refl ow" could
compromise the reliability of their solder joints. Virtually all these devices
demand you "cool down" the Sn63 profi le you are likely using today.
Dynamic control of the remote on/off function is best accomplished with
a mechanical relay or an open-collector/open-drain drive circuit (optically iso-
lated if appropriate). The drive circuit should be able to sink appropriate cur-
rent (see Performance Specifi cations) when activated and withstand appro-
priate voltage when deactivated. Applying an external voltage to pin 2 when
no input power is applied to the converter can cause permanent damage
to the converter.
Figure 10. ULQ SMT DC/DC
With Disposable Heat Shield
Figure 11. Recommended Solder Profi le
(When The Heat-shield Temperature Exceeds +250°C, The Air Within Is 50°C Cooler)
DATEL is not exempted from the Laws of Physics. And we do not have
magic solders no one else has. Nevertheless, we have a simple and practical,
straightforward approach that works. We assemble our SMT DC/DC's on a
hightemperature, plastic lead-frame (nylon 46, UL94V-0 rated) using a high-
temperature (+216°C), lead-free alloy (Sn96.2%, Ag2.5%, Cu0.8%, Sb0.5%).
The lead-frame ensures coplanarity (to within 0.004 in.) of the unit's tin-plated
(150 microinches) copper leads and also supports a removable heat shield.
The disposable heat shield, which has a cutaway exposing the package
leads, provides thermal insulation to internal components during refl ow and
also doubles as the vacuum pick-up location. The insulation properties of the
heat shield are so effective that temperature differentials as high as 50°C
develop inside-to-outside the shield. Oven temperature profi les with peaks of
250-260°C and dwell times exceeding 2 minutes above 221°C (the melting
point of Sn96.5/Ag3.5) are easily achieved. DATEL's new-generation SMT
units are shipped in stackable, JEDEC-style plastic.
Z1 Z2 Z3 Z4 Z5 Z6 Z7
100
Seconds
Degrees Celsius
250
200
150
100
50
200 300 400 500 600
Heat Shield
Test Board
Air Under Shield
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
www.murata-ps.com email: sales@murata-ps.com
21 Feb 2011 MDC_ULQ-15A.B03 Page 8 of 16
Typical Performance Curves, 1.5V Models
92
90
88
86
84
82
80
78
76
74
72
70
68
66
ULQ-1.5/15-D48 Efficiency vs. Line Voltage and Load Current
1.5 3 4.5 6 7.5 9 10.5 12 13.5 15
Load Current
(
Am
p
s
)
Efficiency (%)
V
IN
= 75V
V
IN
= 36V
V
IN
= 48V
91
89
87
85
83
81
79
77
75
73
ULQ-1.5/25-D48 Efficiency vs. Line Voltage and Load Current
2.5 5 7.5 10 12.5 15 17.5 20 22.5 25
Load Current
(
Am
p
s
)
Efficiency (%)
V
IN
= 75V
V
IN
= 36V
V
IN
= 48V
ULQ-1.5/25-D48
Output Current vs. Ambient Temperature
(VIN = 48V, air flow direction from Input pin to Output pin)
Output Current (Amps)
Ambient Temperature (°C)
30
25
20
15
10
5
0
0 lfm
100 lfm
200 lfm
–40 0 253035404550 55 606570 7580 859095100
ULQ-1.5/15-D48
Output Current vs. Ambient Temperature
(No air flow)
Output Current (Amps)
Ambient Temperature (°C)
18
15
12
9
6
3
0
–40 0 253035404550 55 606570 7580 859095100
VIN = 36V
VIN = 75V
VIN = 48V
92
90
88
86
84
82
80
78
76
74
72
70
ULQ-1.5/25-D24 Efficiency vs. Line Voltage and Load Current
2.5 5 7.5 10 12.5 15 17.5 20 22.5 25
Load Current (Amps)
Efficiency (%)
V
IN
= 36V
V
IN
= 18V
V
IN
= 24V
ULQ-1.5/25-D24
Output Current vs. Ambient Temperature
(No air flow)
Output Current (Amps)
Ambient Temperature (°C)
30
25
20
15
10
5
0
VIN = 18V
VIN = 36V
VIN = 24V
–40 0 253035404550 55 606570 7580 859095100
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
www.murata-ps.com email: sales@murata-ps.com
21 Feb 2011 MDC_ULQ-15A.B03 Page 9 of 16
Typical Performance Curves, 1.8V Models
92
90
88
86
84
82
80
78
76
74
72
70
68
ULQ-1.8/25-D48 Efficiency vs. Line Voltage and Load Current
2.1 4.2 6.25 8.3 10.4 12.5 14.6 16.7 18.75 20.8 22.9 25
Load Current (Amps)
Efficiency (%)
V
IN
= 75V
V
IN
= 36V
V
IN
= 48V
ULQ-1.8/25-D48
Output Current vs. Ambient Temperature
(VIN = 48V, air flow direction from Input pin to Output pin)
Output Current (Amps)
Ambient Temperature (°C)
30
25
20
15
10
5
0
0 lfm
100 lfm
200 lfm
–40 0 253035404550 55 606570 7580 859095100
ULQ-1.8/15-D48
Output Current vs. Ambient Temperature
(No air flow)
Output Current (Amps)
Ambient Temperature (°C)
18
15
12
9
6
3
0
–40 0 253035404550 55 606570 7580 859095100
VIN = 36V
VIN = 75V
VIN = 48V
92
90
88
86
84
82
80
78
76
74
72
70
68
ULQ-1.8/15-D48 Efficiency vs. Line Voltage and Load Current
1.5 3 4.5 6 7.5 9 10.5 12 13.5 15
Load Current (Amps)
Efficiency (%)
V
IN
= 75V
V
IN
= 36V
V
IN
= 48V
92
90
88
86
84
82
80
78
76
74
72
70
68
ULQ-1.8/25-D24 Efficiency vs. Line Voltage and Load Current
2.5 5 7.5 10 12.5 15 17.5 20 22.5 25
Load Current (Amps)
Efficiency (%)
V
IN
= 36V
V
IN
= 18V
V
IN
= 24V
ULQ-1.8/25-D24
Output Current vs. Ambient Temperature
(No air flow)
Output Current (Amps)
Ambient Temperature (°C)
30
25
20
15
10
5
0
VIN = 18V
VIN = 36V
VIN = 24V
–40 0 253035404550 55 606570 7580 859095100
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
www.murata-ps.com email: sales@murata-ps.com
21 Feb 2011 MDC_ULQ-15A.B03 Page 10 of 16
92
90
88
86
84
82
80
78
76
74
72
70
ULQ-2/25-D48 Efficiency vs. Line Voltage and Load Current
2.5 5 7.5 10 12.5 15 17.5 20 22.5 25
Load Current (Amps)
Efficiency (%)
V
IN
= 75V
V
IN
= 36V
V
IN
= 48V
92
90
88
86
84
82
80
78
76
74
72
70
68
ULQ-2/15-D48 Efficiency vs. Line Voltage and Load Current
1.5 3 4.5 6 7.5 9 10.5 12 13.5 15
Load Current
(
Am
p
s
)
Efficiency (%)
V
IN
= 75V
V
IN
= 36V
V
IN
= 48V
ULQ-2/15-D48
Output Current vs. Ambient Temperature
(No air flow)
Output Current (Amps)
Ambient Temperature (°C)
18
15
12
9
6
3
0
–40 0 253035404550 55 606570 7580 859095100
VIN = 36V
VIN = 75V
VIN = 48V
92
90
88
86
84
82
80
78
76
74
72
70
ULQ-2/25-D24 Efficiency vs. Line Voltage and Load Current
2.5 5 7.5 10 12.5 15 17.5 20 22.5 25
Load Current (Amps)
Efficiency (%)
V
IN
= 36V
V
IN
= 18V
V
IN
= 24V
ULQ-2/25-D24
Output Current vs. Ambient Temperature
(No air flow)
Output Current (Amps)
Ambient Temperature (°C)
30
25
20
15
10
5
0
VIN = 18V
VIN = 36V
VIN = 24V
–40 0 253035404550 55 606570 7580 859095100
ULQ-2/25-D48
Output Current vs. Ambient Temperature
(VIN = 48V, air flow direction from Input pin to Output pin)
Output Current (Amps)
Ambient Temperature (°C)
30
25
20
15
10
5
0
0 lfm
100 lfm
200 lfm
–40 0 222630343842465054586266707478828690
Typical Performance Curves, 2V Models
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
www.murata-ps.com email: sales@murata-ps.com
21 Feb 2011 MDC_ULQ-15A.B03 Page 11 of 16
Typical Performance Curves, 2.5V Models
ULQ-2.5/15-D48
Output Current vs. Ambient Temperature
(VIN = 48V, air flow direction from Input pin to Output pin)
Output Current (Amps)
Ambient Temperature (°C)
18
15
12
9
6
3
0
Natural Convection
100 lfm
300 lfm
400 lfm
200 lfm
–40 0 253035404550 55 606570 7580 859095100
94
92
90
88
86
84
82
80
78
76
74
72
ULQ-2.5/15-D48 Efficiency vs. Line Voltage and Load Current
1.5 3 4.5 6 7.5 9 10.5 12 13.5 15
Load Current (Amps)
Efficiency (%)
V
IN
= 75V
V
IN
= 36V
V
IN
= 48V
93
91
89
87
85
83
81
79
77
ULQ-2.5/20-D48 Efficiency vs. Line Voltage and Load Current
2 4 6 8 10 12 14 16 18 20
Load Current (Amps)
Efficiency (%)
V
IN
= 75V
V
IN
= 36V
V
IN
= 48V
ULQ-2.5/20-D48
Output Current vs. Ambient Temperature
(VIN = 48V, air flow direction from Input pin to Output pin)
Output Current (Amps)
Ambient Temperature (°C)
25
20
15
10
5
0
100 lfm
200 lfm
300 lfm
400 lfm
–40 0 253035404550 55 606570 7580 859095100
5,1$0OWER$ISSIPATIONVS,OAD#URRENT
,OAD#URRENT!MPS
0OWER$ISSIPATION7ATTS
6
).
6
6
).
6
6
).
6
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
www.murata-ps.com email: sales@murata-ps.com
21 Feb 2011 MDC_ULQ-15A.B03 Page 12 of 16
94
90
86
82
78
74
70
ULQ-3.3/15-D48 Efficiency vs. Line Voltage and Load Current
123456789101112131415
Load Current (Amps)
Efficiency (%)
V
IN
= 75V
V
IN
= 36V
V
IN
= 48V
ULQ-3.3/15-D48
Output Current vs. Ambient Temperature
(VIN = 48V, air flow direction from Input pin to Output pin)
Output Current (Amps)
Ambient Temperature (°C)
18
15
12
9
6
3
0
Natural Convection
100 lfm
300 lfm
400 lfm
200 lfm
–40 0 253035404550 55 606570 7580 859095100
93
91
89
87
85
83
81
79
77
ULQ-3.3/20-D48 Efficiency vs. Line Voltage and Load Current
2 4 6 8 10 12 14 16 18 20
Load Current (Amps)
Efficiency (%)
V
IN
= 75V
V
IN
= 36V
V
IN
= 48V
ULQ-3.3/20-D48
Output Current vs. Ambient Temperature
(VIN = 48V, air flow direction from Input pin to Output pin)
Output Current (Amps)
Ambient Temperature (°C)
25
20
15
10
5
0
100 lfm
200 lfm
300 lfm
–40 0 253035404550 55 606570 7580 859095100
93
91
89
87
85
83
81
79
77
ULQ-3.3/20-D24 Efficiency vs. Line Voltage and Load Current
2 4 6 8 10 12 14 16 18 20
Load Current (Amps)
Efficiency (%)
V
IN
= 36V
V
IN
= 18V
V
IN
= 24V
ULQ-3.3/20-D24
Output Current vs. Ambient Temperature
(VIN = 24V, air flow direction from Input pin to Output pin)
Output Current (Amps)
Ambient Temperature (°C)
25
20
15
10
5
0
0 lfm
100 lfm
200 lfm 400 lfm
–40 0 253035404550 55 606570 7580 859095100
Typical Performance Curves, 3.3V Models
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
www.murata-ps.com email: sales@murata-ps.com
21 Feb 2011 MDC_ULQ-15A.B03 Page 13 of 16
Typical Performance Curves, 5V Models
5,1$.
-AXIMUM/UTPUT#URRENTVS!MBIENT4EMPERATURE
6).6AIRFLOWDIRECTIONFROM)NPUTPINTO/UTPUTPIN
/UTPUT#URRENT!MPS
!MBIENT4EMPERATUREo#
LFM
LFM
LFM
LFM
n
5,1$.%FFICIENCY6S,INE6OLTAGE!ND,OAD#URRENT
,OAD#URRENT!MPS
%FFICIENCY
6IN6
6IN6
6IN6
6IN6
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
www.murata-ps.com email: sales@murata-ps.com
21 Feb 2011 MDC_ULQ-15A.B03 Page 14 of 16
Typical Performance Curves, 12V Models
ULQ-12/10-D48
Output Current vs. Ambient Temperature
(VIN = 48V, air flow direction from Input pin to Output pin)
Output Current (Amps)
Ambient Temperature (°C)
10.5
10
9.5
9
8.5
8
7.5
7
6.5
6
100 lfm
–40 0 222630343842465054586266707478828690
500 lfm
200 lfm
300 lfm
5,1$.
%FFICIENCYVS,INE6OLTAGEAND,OAD#URRENT #
,OAD#URRENT!MPS
%FFICIENCY
6
).
6
6
).
6
6
).
6
5,1$0OWER$ISSIPATIONVS,OAD#URRENT
,OAD#URRENT!MPS
0OWER$ISSIPATION7ATTS
6
).
6
6
).
6
6
).
6
5,1$
-AXIMUM/UTPUT#URRENTVS!MBIENT4EMPERATURE
6).6TRANSVERSEAIRFLOWDIRECTIONFROMn/UTPUTTO/UTPUTPIN
/UTPUT#URRENT!MPS
!MBIENT4EMPERATUREo#
LFM
n
LFM
LFM
LFM
5,1$.
%FFICIENCYVS,INE6OLTAGEAND,OAD#URRENT #
,OAD#URRENT!MPS
%FFICIENCY
6
).
6
6
).
6
6
).
6
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
www.murata-ps.com email: sales@murata-ps.com
21 Feb 2011 MDC_ULQ-15A.B03 Page 15 of 16
PART NUMBER STRUCTURE
Nominal Output Voltage:
1.2,1.5, 1.8, 2, 2.5, 3.3, 5, 12 Volts
3.3
LQ 20-/D48
Input Voltage Range:
D24 = 18-36 Volts (24V nominal)
D48 = 36-75 Volts (48V nominal)
Maximum Rated Output :
Current in Amps
Output
Confi guration:
U = Unipolar
-N
Surface-Mount Package*
*See list on pg. 2 using the C40 SMT package.
M
U
Quarter-Brick Package
Remote On/Off Control Polarity
Add "P" for positive polarity
(pin 2 open = converter on)
Add "N" for negative polarity
(pin 2 open = converter off)
Positive polarity is standard for D24 models.
Negative polarity is standard for D48 models.
Alternate polarities may require a special order.
Output
Confi guration:
U = Unipolar
Lx
Pin Length Option: Through-hole packages only
L1 Pin length 0.110 ±0.010 inches (2.79 ±0.25mm)
L2 Pin length 0.145 ±0.010 inches (3.68 ±0.25mm)
Blank is standard pin length
Note:
Some model number combinations
may not be available. Contact Murata
Power Solutions.
For the surface mount versions of the ULQ, use the Recommended SMT Pad
Layout illustration as a starting point to locate pads to mount the converter.
This diagram is for the pads on the mating printed circuit board—it is not
the dimensions of the lead terminals on the converter. Note: the pads are
slightly larger than the lead terminals to accomodate solder wetting and
meniscus. Also, your particular application may require some deviation from
this diagram.
#OPPER0AD
0#"
3-4
,EAD 3-45NIT
490
2%&
4HESETWOPADSAREFORALIGNMENTANDPOSITIONINGONLY
4HEYARENOTREQUIREDFORELECTRICALCONTACT
Recommended SMT Pad Layout
RoHS-6 Hazardous
Substance Compliant
C
Note: Standard pin length with no
"Lx" suffi x is 0.125" (3.18mm). The
L1 and L2 lengths require a sched-
uled quantity order.
-
ULQ Models
Single Output
, Low-Profi le, Quarter-Brick
8-25 Amp Isolated DC/DC Converters
Murata Power Solutions, Inc. makes no representation that the use of its products in the circuits described herein, or the use of other
technical information contained herein, will not infringe upon existing or future patent rights. The descriptions contained herein do not imply
the granting of licenses to make, use, or sell equipment constructed in accordance therewith. Specifi cations are subject to change without
notice. © 2011 Murata Power Solutions, Inc.
www.murata-ps.com/locations email: sales@murata-ps.com
Murata Power Solutions, Inc.
11 Cabot Boulevard, Mansfi eld, MA 02048-1151 U.S.A.
ISO 9001 and 14001 REGISTERED
21 Feb 2011 MDC_ULQ-15A.B03 Page 16 of 16
