FEATURES
Standard quarter-brick package/pinout
Outputs from 1.5 to 48V up to 125W
Low profi le 0.42" height
24 and 48Vdc nominal inputs
Fully isolated, 2250Vdc (BASIC) insulation
Designed for RoHS-6 compliance
Output overvoltage/short-circuit protected
On/Off control, trim and sense functions
High effi ciency to 92%
Protected against temp. and voltage limits
Designed to meet UL/IEC/EN60950-1 safety
approvals
Typical unit
For effi cient, fully isolated DC power in the small-
est space, Murata Power Solutions' UVQ series
quarter bricks offer output voltages from 1.5
to 48Volts with currents up to 40 Amps. UVQs
operate over a wide temperature range (up to
+70°C at 200 lfm airfl ow) at full-rated power. The
optional mounting baseplate extends this to all
practical temperature ranges at full power.
UVQs achieve these impressive specifi cations
while delivering excellent electrical performance.
Overall noise is 35mVp-p (3.3V models) with fast
step response (down to 50µsec). These convert-
ers offer high stability even with no load and
tight output regulation. The unit is fully protected
against input over and undervoltage, output over-
current and short circuit. An on-board temperature
sensor shuts down the converter if thermal limits
are reached. Protection uses the “hiccup” (auto
restart) method.
A convenient remote On/Off control input oper-
ates by external digital logic, relay or transistor
input. To compensate for longer wiring and to
retain output voltage accuracy at the load, UVQs
include a Sense input to dynamically correct for
ohmic losses. A trim input may be connected to a
user’s adjustment potentiometer or trim resis-
tors for output voltage calibration closer than the
standard accuracy.
UVQs include industry-standard safety certifi ca-
tions and BASIC I/O insulation provides 2250 Volt
input/output isolation. Radiation emission testing
is performed to widely-accepted EMC standards.
The UVQs may be considered as higher perfor-
mance replacements for some Murata Power
Solutions USQ models.
PRODUCT OVERVIEW
–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
Baseplate
(9)
Optional
Figure 1. Simplifi ed Schematic
Typical confi guration — some models use a different topology
MDC_UVQ Models.C03 Page 1 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
www.murata-ps.com
www.murata-ps.com/support
For full details go to
www.murata-ps.com/rohs
　
These are partial model numbers. Please refer to the full model number struc-
ture for complete ordering part numbers.
Min. IOUT = 3 Amps for UVQ-3.3 Vout models.
All specifi cations are at nominal line voltage and full load, +25°C unless other-
wise noted. See detailed specifi cations.
Output capacitors are 1uF ceramic || 10 uF electrolytic. Input cap is 22 uF, low
ESR, except UVQ-24/4.5 is 33uF and UVQ-48/2.5 uses no input cap. I/O caps are
necessary for our test equipment and may not be needed for your application.
IOUT = 14 Amps max. with VIN = 18-19.5 Volts.
UVQ Pin 9 Baseplate Connection
The UVQ series may include an optional installed baseplate for extended
thermal management. Various UVQ models (see list below) are also available
with an additional pin 9 on special order which connects to the baseplate but is
electrically isolated from the rest of the converter. Please refer to the mechani-
cal drawings.
Pin 9 offers a positive method of controlling the electrical potential of the
baseplate, independent of the converter. Some baseplate models cannot
include pin 9 and in such cases, the baseplate is grounded by the mounting
bolts. Or consider adding an external lugged washer with a grounding terminal.
The baseplate may be ordered by adding a “B” to the model number tree
and pin 9 will be pre-installed by adding a “9”. The two options are separate.
Please refer to the Ordering Guide. Do not order pin 9 without the baseplate.
Note that “pin 9” converters may be on limited forecast, requiring minimum
order quantities and scheduled deliveries.
Models available with Pin 9:
UVQ-12/10-D48
UVQ-1.5/40-D24
Models which are NOT available with Pin 9:
UVQ-5/20-D24 and –D48
UVQ-3.3/30-D24
UVQ-3.3/35-D48
UVQ-2.5/35-D24
UVQ-2.5/40-D48
Other models which are not listed will be reviewed for future pin 9 accomo-
dation.
PERFORMANCE SPECIFICATIONS SUMMARY AND ORDERING GUIDE
Root Models
Output Input
Effi ciency) Package
(Case,
Pinout)
VOUT
(Volts)
IOUT
(Amps)
Power
(Watts)
R/N (mVp-p) Regulation (Max.) ➂VIN Nom.
(Volts)
Range
(Volts)
IIN, No Load
(mA)
IIN, Full Load
(Amps)Typ. Max. Line Load Min. Typ.
UVQ-1.5/40-D24P-C 1.5 40 60 30 60 ±0.075% ±0.05% 24 18-36 80 2.84 86.5% 88%
C59, P32
UVQ-2.5/35-D24P-C 2.5 35 87.5
35
60 ±0.05% ±0.05% 24 18-36 100 4.14 86% 88%
UVQ-2.5/40-D48N-C 40 100 60 ±0.05% ±0.05% 48 36-75 100 2.37 87% 88%
UVQ-3.3/30-D24P-C ➁3.3 30 99 65 ±0.1% ±0.25% 24 18-36 180 4.58 88.5% 90%
UVQ-3.3/35-D48N-C ➁35 115.5 40 ±0.05% ±0.25% 48 36-75 130 2.7 87% 89%
UVQ-5/20-D24P-C 5 20 100 30 50 ±0.05% ±0.05% 24 18-36 180 4.53 91% 92%
UVQ-5/20-D48N-C 20 25 ±0.05% ±0.05% 48 36-75 80 2.31 88.5% 90%
UVQ-12/8-D24P-C 12 8 96 95 130 ±0.1% ±0.1% 24 18-36 90 4.4 89% 91%
UVQ-12/10-D48N-C 10 120 110 160 ±0.075% ±0.05% 48 36-75 60 2.78 88.5% 90%
UVQ-15/7-D24P-C 15 7 105 85 150 ±0.05% ±0.05% 24 18-36 103 4.85 88.5% 90.3%
UVQ-15/7-D48N-C 120 150 ±0.05% ±0.02% 48 36-75 60 2.39 90% 91.5%
UVQ-18/5.6-D24P-C 18 5.6 100.8 125 185 ±0.05% ±0.075% 24 18-36 140 4.69 88% 89.5%
UVQ-18/6-D48N-C 6
108
125 185 ±0.05% ±0.075% 48 36-75 80 2.5 88.3% 90%
UVQ-24/4.5-D24P-C 24 4.5 60 100 ±0.075% ±0.15% 24 18-36 45 5.03 88% 89.5%
UVQ-24/4.5-D48N-C 75 130 ±0.075% ±0.25% 48 36-75 45 2.49 89% 90.5%
UVQ-48/2.5-D24P-C 48 2.5 120 100 200 ±0.1% ±0.2% 24 18-36 45 4.4 89% 91%
UVQ-48/2.5-D48N-C 250 375 ±0.175% ±0.2% 48 36-75 30 2.71 91% 92.3%
Model UVQ-31128-C is a standard model UVQ-5/20-D48NB-C with modifi ed rise time to reach 4.75V within 10 mSec. All other specifi cations are as per the
standard product.
MDC_UVQ Models.C03 Page 2 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
www.murata-ps.com/support
PART NUMBER STRUCTURE
U VQ 3.3 20 D48
-/-
Quarter-Brick Package
Output Confi guration
U = Unipolar/Single
Nominal Output Voltage
1.2 to 48 Volts
Maximum Rated Output
Current in Amps Blank = No baseplate, standard
B = Baseplate installed, optional special order
Baseplate Pin 9, see Mechanical Drawings: (special order)
Blank = No pin 9, standard
9 = Pin 9 installed (see description on pg. 2), optional
Alternate Pin Length:
Blank = Standard pin length
L1 = 0.110 (2.79mm)
L2 = 0.145 (3.68mm)
Input Voltage Range:
D24 = 18-36 Volts (24V nominal)
D48 = 36-75 Volts (48V nominal)
* Note:
Some model number combinations may not be
available. Contact Murata Power Solutions.
Remote On/Off Control Logic:
Add "P" for positive logic
Add "N" for negative logic
Positive "P" logic is standard for D24 models and
optional special order for D48 models. Negative "N"
logic is standard for D48 models and optional special
order for D24 models.
B LX9
N-C
RoHS-6 hazardous substance compliant
(does not claim EU RoHS exemption 7b–lead in solder)
(special quantity order)
ORDERING GUIDE SUMMARY
Model VOUT Range IOUT Range VIN Range Effi ciency
All Models 1.2V to 48V 2.5A to 40A 18-36V or 36-75V Up to 92.%, model dependent
INPUT CHARACTERISTICS
Parameter Typ. @ 25°C, full load Notes
Voltage Range 18-36 or 36-75 Volts 24V or 48V nominal
Current, full power Up to 5.6 Amps Model dependent
Isolation 2kVdc to 2250V Model dependent
Remote On/Off Control Switch or FET control Positive or negative logic
OUTPUT CHARACTERISTICS
Parameter Typ. @ 25°C, full load Notes
Voltage 1.5 to 48 Volts ±10% Trimmable
Current 2.5 to 40 Amps fullscale No minimum load
Accuracy Down to 1% of VNOM Most models
Ripple & Noise (to 20MHz) Down to 35mVp-p Model dependent
Line and Load Regulation Down to ±0.125%/±0.25% Model dependent
Overcurrent Protection 150% of IOUT max. With hiccup auto-restart
Overtemperature Protection +125°C
Effi ciency (minimum) See Performance Specifi cations
GENERAL SPECIFICATIONS
Parameter Typ. @ 25°C, full load Notes
Dynamic Load Response Down to 50sec Model dependent
Operating Temperature Range –40 to +110°C With baseplate, see derating curve
Safety UL/IEC/EN 60950-1 and CSA C22.2-No.234
MECHANICAL CHARACTERISTICS
With baseplate 1.45 x 2.30 x 0.5 inches (36.83 x 58.42 x 12.7 mm)
Without baseplate 1.45 x 2.30 x 0.42 inches (36.83 x 58.42 x 10.67 mm)
See Performance Specifi cations, page 2
MDC_UVQ Models.C03 Page 3 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
www.murata-ps.com/support
MDC_UVQ Models.C03 Page 4 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
Performance/Functional Specifi cations 24V Models
Typical @ TA = +25°C under nominal line voltage, nominal output voltage, natural air convection, external caps and full-load conditions, unless noted. (1)
UVQ-1.5/40-D24
UVQ-2.5/35-D24
UVQ-3.3/30-D24
UVQ-5/20-D24
UVQ-12/8-D24
UVQ-15/7-D24
UVQ-18/5.6-D24
UVQ-24/4.5-D24
UVQ-48/2.5-D24
Input
Input voltage range See ordering guide
Start-up threshold, (V) min. 17 17 17 17 17 17 17 17 17
Undervoltage
shutdown, (V)14 16 16.25 16 16.25 16 16
Overvoltage shutdown (V) none 39 none
Refl ected (back) ripple
current210-50 mA pk-pk, model dependent
Input Current
Full load conditions See ordering guide.
Inrush transient, (A2sec) 0.5 0.5 0.05 0.5 0.1 1 1 0.05 0.05
Output short circuit, (mA) 40 50 10 320 50 50 50
No load, mA 80 100 180 160 90 103 140 45 30
Low line (VIN = min.),
(Amps) 3.79 5.49 6.04 5.57 5.93 6.52 6.29 6.67 3.60
Standby mode,
(Off, UV, OT shutdown) 1-4mA, model dependent
Internal input fi lter type L-C Pi-type L-C
Reverse polarity
protection See notes.
Remote On/Off Control5
Positive logic, "P" suffi x
(specifi cations are max)
OFF = Ground pin to +0.8V
ON = Open or +5V to +VIN max.
Negative logic, "N" suffi x
(specifi cations are max)
OFF = Open or +5V to +VIN max
ON = Ground pin to+0.8V max
Current 1-8 mA, model dependent
www.murata-ps.com/support
MDC_UVQ Models.C03 Page 5 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
UVQ-1.5/40-D24
UVQ-2.5/35-D24
UVQ-3.3/30-D24
UVQ-5/20-D24
UVQ-12/8-D24
UVQ-15/7-D24
UVQ-18/5.6-D24
UVQ-24/4.5-D24
UVQ-48/2.5-D24
Output
Voltage output range See ordering guide.
Voltage output accuracy
(50% load) ±1.5% of VNOM ±1.25% of VNOM ±1% of VNOM
Adjustment range –20 to +10% of VNOM. ±10% of VNOM.
Temperature coeffi cient ±0.02% of VOUT range per °C
Minimum loading No minimum load 3 amps No minimum load
Remote sense
compensation +10%.
Ripple/noise See ordering guide.
Line/Load regulation See ordering guide.
Effi ciency See ordering guide.
Maximum capacitive
loading, Low ESR
<0.02 max.,
resistive load, (F)
10,000 5000 4700 2200
Current limit inception
(98% of VOUT, after
warmup), (Amps)
45 44 36 24 10 9.5 7.2 5.8 3.4
Short circuit protection
method Current limiting, hiccup autorestart. Remove overload for recovery.
Short circuit current,
(Amps) 3.6 3 3 3 1.5 15 mA 3 5 2.8
Short circuit duration Output may be shorted continuously to ground (no damage).
Overvoltage protection, (via
magnetic feedback) 2.3 Volts 3 Volts max 4 Volts max 6.8 Volts max 14.4 Volts
max 18.5 Volts 22 Volts max 29 Volts max 59 Volts max
Isolation Characteristics
Isolation Voltage
Input to Output, (Volts min) 2000
Input to baseplate 1500
Baseplate to output,
(Volts min) 1500 1000 1500
Isolation resistance 100 MΩ
Isolation capacitance, (pF) 1500 1000 2000 50
Isolation safety rating Basic insulation
Performance/Functional Specifi cations 24V Models
Typical @ TA = +25°C under nominal line voltage, nominal output voltage, natural air convection, external caps and full-load conditions, unless noted. (1)
www.murata-ps.com/support
UVQ-1.5/40-D24
UVQ-2.5/35-D24
UVQ-3.3/30-D24
UVQ-5/20-D24
UVQ-12/8-D24
UVQ-15/7-D24
UVQ-18/5.6-D24
UVQ-24/4.5-D24
UVQ-48/2.5-D24
Dynamic characteristics
Dynamic load response
(50-75-50% load step)
100 µSec to
±1%
of fi nal value
150 µSec to
±1.5%
of fi nal value
150 µSec to
±1.5%
of fi nal value
100 µSec to
±1.5% of fi nal
value
50 µSec
to ±1%
of fi nal value
40 µSec to
±1.25%
of fi nal value
50 µSec to
±1%
of fi nal value
100 µSec
to ±1%
of fi nal value
100 µSec
to ±1%
of fi nal value
Start-up time
VIN to VOUT regulated, mSec
Remote On/Off to VOUT
regulated, mSec
90msec
90msec
50msec
50msec
50msec
50msec
200msec
200msec
40msec
30msec
30msec
25msec
30msec
35msec
290msec
200msec
100msec
100msec
Switching frequency, (KHz) 380 ± 30 500 to 650 600 360 290 ± 30 242 240 ± 25 290 ± 30 250 ± 25
Environmental
Calculated MTBF4TBD
Operating temperature
range: see Derating
Curves.
−40 to +85°C (with Derating, see Note 15.)
Operating temperature,
with baseplate, no
derating required (°C)3
−40 to +110 −40 to +115 −40 to +110
Storage temperature (°C) −55 to +130 −55 to +125
Thermal protection/
shutdown +110 to 125°C, model dependent
Relative humidity To +85°C/85%, non-condensing
Physical
Outline dimensions See mechanical specs.
Baseplate material Aluminum
Pin material Copper alloy
Pin diameter 0.040/0.062 inches (1.016/1.575 mm)
Weight 1.55 ounce
(44 grams) 1 ounce (28 grams)
Electromagnetic
interference
(conducted and
radiated)
(external fi lter required)
Designed to meet FCC part 15, class B, EN55022
Safety Designed to meet UL/cUL 60950-1, CSA C22.2 No.60950-1, IEC/EN 60950-1
MDC_UVQ Models.C03 Page 6 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
Performance/Functional Specifi cations 24V Models
Typical @ TA = +25°C under nominal line voltage, nominal output voltage, natural air convection, external caps and full-load conditions, unless noted. (1)
www.murata-ps.com/support
MDC_UVQ Models.C03 Page 7 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
Performance/Functional Specifi cations 48V Models
Typical @ TA = +25°C under nominal line voltage, nominal output voltage, natural air convection, external caps and full-load conditions, unless noted. (1)
UVQ-2.5/40-D48
UVQ-3.3/35-D48
UVQ-5/20-D48
UVQ-12/10-D48
UVQ-15/7-D48
UVQ-18/6-D48
UVQ-24/4.5-D48
UVQ-48/2.5-D48
Input
Input voltage range See ordering guide
Start-up threshold, min (V) 35 34.5 34 34.5 35
Undervoltage
shutdown, (V)14 33.5 32 33.5
Overvoltage shutdown (V) none
Refl ected (back) ripple
current 10-50 mA pk-pk, model dependent
Input Current
Full load conditions See ordering guide.
Inrush transient, (A2sec) 0.05 0.05 1 1 0.05 1 0.05 0.05
Output short circuit, (mA) 50 10 30 50 250 50
No load, mA 100 130 80 60 30 80 45 30
Low line (VIN = min.),
(Amps) 3.15 3.56 3.07 3.72 3.21 3.35 3.30 3.60
Standby mode,
(Off, UV, OT shutdown) 1-4mA, model dependent
Internal input fi lter type L-C Pi-type L-C
Reverse polarity
protection See notes.
Remote On/Off Control5
Positive logic, "P" suffi x
(specifi cations are max)
OFF = Ground pin to +0.8V
ON = Open or +5V to +VIN max
Negative logic, "N" suffi x
(specifi cations are max)
OFF = Open or +5V to +VIN max
ON = Ground pin to+0.8V max
Current 1-8 mA, model dependent
www.murata-ps.com/support
MDC_UVQ Models.C03 Page 8 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
UVQ-2.5/40-D48
UVQ-3.3/35-D48
UVQ-5/20-D48
UVQ-12/10-D48
UVQ-15/7-D48
UVQ-18/6-D48
UVQ-24/4.5-D48
UVQ-48/2.5-D48
Output
Voltage output range See ordering guide.
Voltage output accuracy
(50% load) ±1.5% of VNOM ±1.25% of VNOM ±1% of VNOM
Adjustment range –20 to +10% of VNOM. +10% of VNOM.
Temperature coeffi cient ±0.02% of VOUT range per °C
Minimum loading No minimum
load 3 Amps No minimum
load No minimum load
Remote sense
compensation +10%.
Ripple/noise See ordering guide.
Line/Load regulation See ordering guide.
Effi ciency See ordering guide.
Maximum capacitive
loading, Low ESR
<0.02 max.,
resistive load, (F)
10,000 4700 2200 1000
Current limit inception
(98% of VOUT, after
warmup), (Amps)
46 48 26 12.5 8.5 7 6.5 3.3
Short circuit protection
method Current limiting, hiccup autorestart. Remove overload for recovery.
Short circuit current,
(Amps) 5 0.1 1.5 3 3 3 3.5
Short circuit duration Output may be shorted continuously to ground (no damage).
Overvoltage protection, (via
magnetic feedback) 3 Volts max 4 Volts max 6 Volts max 14.4 Volts max 18.5 Volts max 22 Volts max 29 Volts max 55 Volts max
Isolation Characteristics
Isolation Voltage
Input to Output, (Volts min) 2250
Input to baseplate 1500
Baseplate to output,
(Volts min) 1500 1500
Isolation resistance 100 MΩ
Isolation capacitance, (pF) 1500 1000 50 50 1500
Isolation safety rating Basic insulation
Performance/Functional Specifi cations 48V Models
Typical @ TA = +25°C under nominal line voltage, nominal output voltage, natural air convection, external caps and full-load conditions, unless noted. (1)
www.murata-ps.com/support
MDC_UVQ Models.C03 Page 9 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
UVQ-2.5/40-D48
UVQ-3.3/35-D48
UVQ-5/20-D48
UVQ-12/10-D48
UVQ-15/7-D48
UVQ-18/6-D48
UVQ-24/4.5-D48
UVQ-48/2.5-D48
Dynamic characteristics
Dynamic load response
(50-75-50% load step)
150 µSec to
±1.5%
of fi nal value
150 µSec to
±1.5%
of fi nal value
90 µSec
to ±2%
of fi nal value
50 µSec to ±1%
of fi nal value
50 µSec to ±1%
of fi nal value
50 µSec to ±1%
of fi nal value
100 µSec
to ±1%
of fi nal value
75 µSec
to ±1%
of fi nal value
Start-up time
VIN to VOUT regulated, mSec
Remote On/Off to VOUT
regulated, mSec
50msec
50msec
50msec
50msec
50msec
50msec
40msec
30msec
30msec
30msec
30msec
30msec
100msec
100msec
50msec
50msec
Switching frequency, (KHz) 600 600 450 ± 50 290 ± 30 245 ± 20 240 ± 25 290 ± 30 540 ± 40
Environmental
Calculated MTBF4TBD
Operating temperature
range: see Derating
Curves.
−40 to +85°C (with Derating, see Note 15.)
Operating temperature,
with baseplate, no
derating required (°C)3
−40 to +110 −40 to +115 −40 to +110 −40 to +110 −40 to +120
Storage temperature (°C) −55 to +125
Thermal protection/
shutdown +110 to 125°C, model dependent
Relative humidity To +85°C/85%, non-condensing
Physical
Outline dimensions See mechanical specs.
Baseplate material Aluminum
Pin material Copper alloy
Pin diameter 0.040/0.062 inches (1.016/1.575 mm)
Weight 1 ounce (28 grams)
Electromagnetic
interference
(conducted and
radiated)
(external fi lter required)
Designed to meet FCC part 15, class B, EN55022
Safety Designed to meet UL/cUL 60950-1, CSA C22.2 No.60950-1, IEC/EN 60950-1
Performance/Functional Specifi cations 48V Models
Typical @ TA = +25°C under nominal line voltage, nominal output voltage, natural air convection, external caps and full-load conditions, unless noted. (1)
www.murata-ps.com/support
TYPICAL PERFORMANCE DATA
16
14
12
10
8
6
4
2
0
UVQ-2.5/40-D48
Power Dissipation vs. Load Current @ 25°C
0 5 10 15 20 25 30 35 40
Load Current (Amps)
Power Dissipation (Watts)
V
IN
= 48V
92
88
84
80
76
72
68
64
62
UVQ-2.5/40-D48N
Efficiency vs. Line Voltage and Load Current @ 25°C
0 5 10 15 20 25 30 35 40
Load Current (Amps)
Efficiency (%)
V
IN
= 36V
V
IN
= 48V
V
IN
= 75V
UVQ-1.5/40-D24N: Maximum Current Temperature Derating
(No baseplate, VIN = 24V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
40
39
38
37
36
35
34
33
20 25 30 35 40 45 50 55 60 65 70 75 80 85
400 lfm
100 lfm
Natural convection
200 lfm
200 lfm
UVQ-1.5/40-D24N: Maximum Current Temperature Derating
(With baseplate, VIN = 24V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
40
39
38
37
36
35
34
33
20 25 30 35 40 45 50 55 60 65 70 75 80 85
400 lfm
100 lfm
Natural convection
UVQ-3.3/30-D24N: Maximum Current Temperature Derating
(No baseplate, VIN = 24V, transverse air flow at sea level)
Output Current (Amps)
Ambient Temperature (oC)
30
29
28
27
26
25
24
23
22
21
20
19
18
17
20 25 30 35 40 45 50 55 60 65 70 75 80 85
200 lfm
400 lfm
300 lfm
100 lfm
Natural convection
UVQ-3.3/30-D24N: Maximum Current Temperature Derating
(With baseplate, VIN = 24V, transverse air flow at sea level)
Output Current (Amps)
Ambient Temperature (oC)
30
29
28
27
26
25
24
23
22
21
20 25 30 35 40 45 50 55 60 65 70 75 80 85
200 lfm
400 lfm
300 lfm
100 lfm
Natural convection
MDC_UVQ Models.C03 Page 10 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
www.murata-ps.com/support
TYPICAL PERFORMANCE DATA
1
2
3
4
5
6
7
8
9
10
56.589.5 11 12.5 14 15.5 17 18.5 20
UVQ-5/20-D24
Power Dissipation vs. Load Current @ +25°C
Load Current (Amps)
V
IN
= 18V
V
IN
= 24V
V
IN
= 30V
V
IN
= 36V
Power Dissipation (Watts)
84
85
86
87
88
89
90
91
92
93
94
56.589.5 11 12.5 14 15.5 17 18.5 20
UVQ-5/20-D24P
Efficiency vs. Line Voltage and Load Current @ +25°C
Load Current (Amps)
Efficiency (%)
V
IN
= 18V
V
IN
= 24V
V
IN
= 30V
V
IN
= 36V
14
14.5
15
15.5
16
16.5
17
17.5
18
18.5
19
19.5
20
20 25 30 35 40 45 50 55 60 65 70 75 80 85
Natural convection
100 lfm
200 lfm
300 lfm
400 lfm
UVQ-5/20-D24P: Maximum Current Temperature Derating
(No baseplate, VIN = 24V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
15.5
16
16.5
17
17.5
18
18.5
19
19.5
20
20 25 30 35 40 45 50 55 60 65 70 75 80 85
Natural convection
100 lfm
200 lfm
300 lfm
400 lfm
UVQ-5/20-D24PB: Maximum Current Temperature Derating
(With baseplate, VIN = 24V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
Output Current (Amps)
36
34
32
30
28
26
24
22
20
18
400 lfm
Natural Convection
200 lfm
300 lfm
100 lfm
UVQ-3.3/35-D48 Maximum Current Temperature Derating
(With baseplate, VIN = 48V, transverse air flow at sea level)
Ambient Temperature (oC)
20 25 30 35 40 45 50 55 60 65 70 75 80 85
MDC_UVQ Models.C03 Page 11 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
www.murata-ps.com/support
TYPICAL PERFORMANCE DATA
UVQ-5/20-D48P: Maximum Current Temperature Derating
(No baseplate, VIN = 48V, transverse air flow at sea level)
Output Current (Amps)
Ambient Temperature (oC)
21
20
19
18
17
16
15
14
13
12
20 25 30 35 40 45 50 55 60 65 70 75 80 85
200 lfm
400 lfm
300 lfm
100 lfm
Natural convection
UVQ-5/20-D48PB: Maximum Current Temperature Derating
(With baseplate, VIN = 48V, transverse air flow at sea level)
Output Current (Amps)
Ambient Temperature (oC)
21
20
19
18
17
16
15
14
13
20 25 30 35 40 45 50 55 60 65 70 75 80 85
200 lfm
400 lfm
300 lfm
100 lfm
92
88
84
80
76
72
68
64
62
UVQ-5/20-D48
Efficiency vs. Line Voltage and Load Current @ 25°C
0 2 4 6 8 10 12 14 16 18 20
Load Current (Amps)
Efficiency (%)
V
IN
= 36V
V
IN
= 48V
V
IN
= 75V
6.8
7.0
7.2
7.4
7.6
7.8
8.0
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90
100 lfm
200 lfm
300 lfm
UVQ-12/8-D24P: Maximum Current Temperature Derating
(No baseplate, VIN = 24V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
75
80
85
90
95
0.8 1.6 2.4 3.2 4 4.8 5.6 6.4 7.2 8
VIN = 18V
VIN = 24V
VIN = 30V
VIN = 36V
UVQ-12/8-D24P
Efficiency vs. Line Voltage and Load Current @ +25°C
Load Current (Amps)
Efficiency (%)
78
80
82
84
86
88
90
92
12345678910
UVQ-12/10-D48N
Efficiency vs. Line Voltage and Load Current @ +25°C
Load Current (Amps)
Efficiency (%)
V
IN
= 36V
V
IN
= 48V
V
IN
= 60V
V
IN
= 75V
MDC_UVQ Models.C03 Page 12 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
www.murata-ps.com/support
TYPICAL PERFORMANCE DATA
6.0
6.5
7.0
7.5
8.0
8.5
9.0
9.5
10.0
20 25 30 35 40 45 50 55 60 65 70 75 80 85
Natural convection
100 lfm
200 lfm
300 lfm
400 lfm
UVQ-12/10-D48N: Maximum Current Temperature Derating
(With baseplate, VIN = 48V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
80
82
84
86
88
90
92
94
0.7 1.4 2.1 2.8 3.5 4.2 4.95.6 6.3 7
VIN = 18V
VIN = 24V
VIN = 30V
VIN = 36V
UVQ-15/7-D24N
Efficiency vs. Line Voltage and Load Current @ +25°C
Load Current (Amps)
Efficiency (%)
5
6
7
8
9
10
20 25 30 35 40 45 50 55 60 65 70 75 80 85
Natural convection
100 lfm
200 lfm
300 lfm
400 lfm
UVQ-12/10-D48N: Maximum Current Temperature Derating
(No baseplate, VIN = 48V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
1
3
5
7
9
11
13
15
12345678910
VIN = 75V
VIN = 60V
VIN = 48V
VIN = 36V
UVQ-12/10-D48N
Power Dissipation vs. Load Current @ +25°C
Load Current (Amps)
Power Dissipation (Watts)
1
3
5
7
9
11
13
0.71.42.12.83.54.2 4.95.6 6.3 7
VIN = 36V
VIN = 30V
VIN = 24V
VIN = 18V
UVQ-15/7-D24N
Power Dissipation vs. Load Current @ +25°C
Load Current (Amps)
Power Dissipation (Watts)
4
4.5
5
5.5
6
6.5
7
7.5
Natural convection
100 lfm
200 lfm
300 lfm
400 lfm
UVQ-15/7-D24N: Maximum Current Temperature Derating
(No baseplate, VIN = 24V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90
MDC_UVQ Models.C03 Page 13 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
www.murata-ps.com/support
TYPICAL PERFORMANCE DATA
4.0
4.2
4.4
4.6
4.8
5.0
5.2
5.4
5.6
5.8
6.0
6.2
6.4
6.6
6.8
7.0
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90
Natural convection
100 lfm
200 lfm
300 lfm
400 lfm
UVQ-15/7-D48N: Maximum Current Temperature Derating
(No baseplate, VIN = 48V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
4.0
4.2
4.4
4.6
4.8
5.0
5.2
5.4
5.6
5.8
6.0
6.2
6.4
6.6
6.8
7.0
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90
Natural convection
100 lfm
200 lfm
300 lfm
UVQ-15/7-D48N: Maximum Current Temperature Derating
(With baseplate, VIN = 48V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
1
2
3
4
5
6
7
8
9
10
11
0.7 1.4 2.1 2.8 3.5 4.2 4.95.6 6.3 7
VIN = 75V
VIN = 60V
VIN = 48V
VIN = 36V
UVQ-15/7-D48N
Power Dissipation vs. Load Current @ +25°C
Load Current (Amps)
Power Dissipation (Watts)
76
78
80
82
84
86
88
90
92
94
0.7 1.4 2.1 2.8 3.5 4.2 4.9 5.6 6.3 7
UVQ-15/7-D48N
Efficiency vs. Line Voltage and Load Current @ +25°C
Load Current (Amps)
Efficiency (%)
VIN = 36V
VIN = 48V
VIN = 60V
VIN = 75V
4
4.5
5
5.5
6
6.5
7
7.5
Natural convection
100 lfm
200 lfm
300 lfm
400 lfm
UVQ-15/7-D24N: Maximum Current Temperature Derating
(With baseplate, VIN = 24V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90
92
90
88
86
84
82
80
78
76
UVQ-18/5.6-D24
Efficiency vs. Line Voltage and Load Current @ 25°C
0.56 1.12 1.68 2.24 2.8 3.36 3.92 4.48 5.04 5.6
Efficiency (%)
Load Current (Amps)
VIN = 18V
VIN = 24V
VIN = 36V
MDC_UVQ Models.C03 Page 14 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
www.murata-ps.com/support
TYPICAL PERFORMANCE DATA
95
90
85
80
75
70
65
60
UVQ-18/6-D48N
Efficiency vs. Line Voltage and Load Current @ 25°C
0.6 1.2 1.8 2.4 3 3.6 4.2 4.8 5.4 6
Load Current (Amps)
Efficiency (%)
V
IN
= 36V
V
IN
= 48V
V
IN
= 75V
UVQ-18/5.6-D24: Maximum Current Temperature Derating
(With baseplate, VIN = 24V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
5.8
5.6
5.4
5.2
5
4.8
4.6
4.4
4.2
4
20 25 30 35 40 45 50 55 60 65 70 75 80 85
200 lfm
400 lfm
300 lfm
100 lfm
Natural
Convection
UVQ-18/5.6-D24: Maximum Current Temperature Derating
(No baseplate, VIN = 24V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
5.8
5.6
5.4
5.2
5
4.8
4.6
4.4
4.2
4
3.8
3.6
3.4
20 25 30 35 40 45 50 55 60 65 70 75 80 85
200 lfm
400 lfm
300 lfm
100 lfm
Natural
Convection
16
14
12
10
8
6
4
2
0
UVQ-18/6-D48
Power Dissipation vs. Load Current @ 25°C
Load Current (Amps)
Power Dissipation (Watts)
V
IN
= 48V
V
IN
= 75V
V
IN
= 36V
0.6 1.2 1.8 2.4 3 3.6 4.2 4.8 5.4 6
UVQ-18/6-D48: Maximum Current Temperature Derating
(With baseplate, VIN = 48V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
6.5
6
5.5
5
4.5
4
3.5
20 25 30 35 40 45 50 55 60 65 70 75 80 85
200 lfm
500 lfm
300 lfm
100 lfm
UVQ-18/6-D48: Maximum Current Temperature Derating
(No baseplate, VIN = 48V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
6.5
6
5.5
5
4.5
4
3.5
20 25 30 35 40 45 50 55 60 65 70 75 80 85
200 lfm
500 lfm
300 lfm
100 lfm
MDC_UVQ Models.C03 Page 15 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
www.murata-ps.com/support
TYPICAL PERFORMANCE DATA
3.0
3.3
3.5
3.8
4.0
4.3
4.5
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90
400 lfm
300 lfm
200 lfm
100 lfm
UVQ-24/4.5-D48N: Maximum Current Temperature Derating
(No baseplate, VIN = 48V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
20 25 30 35 40 45 50 55 60 65 70 75 80 85
2.50
2.75
3.00
3.25
3.50
3.75
4.00
4.25
4.50
UVQ-24/4.5-D24P: Maximum Current Temperature Derating
(No baseplate, Vin= 24V, air flow is from Pin 1 to Pin 3)
Output Current (Amps)
Ambient Temperature (oC)
400 LFM
300 LFM
200 LFM
100 LFM
LOW LFM
20 25 30 35 40 45 50 55 60 65 70 75 80 85
2.50
2.75
3.00
3.25
3.50
3.75
4.00
4.25
4.50
UVQ-24/4.5-D24P: Maximum Current Temperature Derating
(With baseplate, Vin= 24V, air flow is from Pin 1 to Pin 3)
Output Current (Amps)
Ambient Temperature (oC)
400 LFM
300 LFM
200 LFM
100 LFM
LOW LFM
80
81
82
83
84
85
86
87
88
89
90
91
1.00 1.35 1.70 2.05 2.40 2.75 3.10 3.45 3.80 4.15 4.50
VIN = 18V
VIN = 24V
VIN = 30V
VIN = 36V
UVQ-24/4.5-D24N
Efficiency vs. Line Voltage and Load Current @ +25°C
Load Current (Amps)
Efficiency (%)
1.00 1.35 1.70 2.05 2.40 2.75 3.10 3.45 3.80 4.15 4.50
64
66
68
70
72
74
76
78
80
82
84
86
88
90
92
UVQ-24/4.5-D48N
Efficiency vs. Line Voltage and Load Current @ +25°C
Load Current (Amps)
Efficiency (%)
V
IN
= 36V
V
IN
= 48V
V
IN
= 60V
V
IN
= 75V
MDC_UVQ Models.C03 Page 16 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
www.murata-ps.com/support
TYPICAL PERFORMANCE DATA
93
92
91
90
89
88
87
86
85
UVQ-48/2.5-D48N
Efficiency vs. Line Voltage and Load Current @ 25°C
0.25 0.5 0.75 1 1.25 1.5 1.75 2 2.25 2.5
Load Current (Amps)
Efficiency (%)
V
IN
= 36V
V
IN
= 48V
V
IN
= 60V
V
IN
= 75V
UVQ-48/2.5-D48N: Maximum Current Temperature Derating
(With baseplate, VIN = 48V, transverse air flow)
Output Current (Amps)
Ambient Temperature (oC)
2.6
2.5
2.4
2.3
2.2
2.1
2.0
20 25 30 35 40 45 50 55 60 65 70 75 80 85
200 lfm
100 lfm
Natural convection
MDC_UVQ Models.C03 Page 17 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
www.murata-ps.com/support
MECHANICAL SPECIFICATIONS
2.30 (58.4)
2.00 (50.8) A
A
PINS 1-3, 5-7: 0.040 ±0.002 (1.016 ±0.05)
PINS 4 & 8: 0.062 ±0.002 (1.575 ±0.05)
0.42
(10.7)
0.188
(4.78)
1.45
(36.8)
B
0.600
(15.24)
4 EQ. SP.
@ 0.150
(3.81)
B
BOTTOM VIEW
8
7
6
5
4
3
2
1
2.30 (58.4)
2.00 (50.8)
0.15 (3.81)
A
1.860 (47.2) A
A
#M3-THREAD X 0.15 DEEP
TYPICAL (4) PLACES
BASEPLATE
0.50
(12.7)
0.188
(4.8)
1.45
(36.8)
1.030
(26.2)
B
0.600 (15.24)
4 EQ. SP.
@ 0.150 (3.81)
B B
BOTTOM VIEW
Optional pin 9 connects
to baseplate. Electrically
isolated from converter.
8
7
6
5
4
3
2
1
9
PINS 1-3, 5-7: 0.040 ±0.002 (1.016 ±0.05)
PINS 4 & 8: 0.062 ±0.002 (1.575 ±0.05)
Alternate pin lengths are available. Contact Murata Power Solutions.
Optional baseplate pin
is special order.
Contact Murata Power Solutions..
* 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.
Important: If sense inputs are not
connected to a remote load, connect
them to their respective VOUT pins at
the converter.
DOSA-Compatible
I/O Connections
Pin Function P32
1–Vin*
2On/Off Control
3+Vin*
4 –Vout
5–Sense
6Output Trim
7+Sense
8 +Vout
Case C59 Case C59 with Baseplate
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˚
MDC_UVQ Models.C03 Page 18 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
www.murata-ps.com/support
Input Voltage 24V models 48V models
Continuous 0 to +36V 0 to +75V
Transient (100 mS) +50V +100V
On/Off Control –0.3 V min to +13.5V max.
Input Reverse Polarity Protection See Fuse section
Output Overvoltage VOUT +20% max.
Output Current (Note 7) Current-limited. Devices can withstand
sustained short circuit without damage.
Storage Temperature –55 to +125°C
Lead Temperature See soldering guidelines
Absolute maximums are stress ratings. Exposure of devices to greater than
any of these conditions may adversely affect long-term reliability. Proper
operation under conditions other than those listed in the Performance/Func-
tional Specifi cations Table is not implied nor recommended.
(1) All models are tested and specifi ed with 200 LFM airfl ow, external 1||10µF ceramic/
tantalum output capacitors. External input capacitance varies according to model type.
All capacitors are low ESR types. These capacitors are necessary to accommodate
our test equipment and may not be required to achieve specifi ed performance in your
applications. All models are stable and regulate within spec under no-load conditions.
General conditions for Specifi cations are +25°C, VIN =nominal, VOUT = nominal, full load.
(2) Input Ripple Current is tested and specifi ed over a 5-20MHz bandwidth. Input fi lter-
ing is CIN = 33µF tantalum, CBUS = 220µF electrolytic, LBUS = 12µH.
(3) Note that Maximum Power Derating curves indicate an average current at nominal
input voltage. At higher temperatures and/or lower airfl ow, the DC/DC converter will
tolerate brief full current outputs if the total RMS current over time does not exceed
the Derating curve.
(4) Mean Time Before Failure is calculated using the Telcordia (Belcore) SR-332 Method1,
Case 3, ground fi xed conditions, TPCBOARD = +25°C, full output load, natural air
convection.
(5) The On/Off Control may be driven with external logic or by applying appropriate
external voltages which are referenced to Input Common. The On/Off Control Input
should use either an open collector/open drain transistor or logic gate which does
not exceed +13.5V.
(6) Short circuit shutdown begins when the output voltage degrades approximately 2%
from the selected setting.
(7) The outputs are not intended to sink appreciable reverse current.
(8) Output noise may be further reduced by adding an external fi lter. See I/O Filtering
and Noise Reduction.
(9) All models are fully operational and meet published specifi cations, including “cold
start” at –40°C.
(10) Regulation specifi cations describe the deviation as the line input voltage or output
load current is varied from a nominal midpoint value to either extreme.
(11) Overvoltage shutdown on 48V input models is not supplied in order to comply with
telecom reliability requirements. These requirements attempt continued operation
despite signifi cant input overvoltage.
(12) Do not exceed maximum power specifi cations when adjusting the output trim.
(13) Note that the converter may operate up to +110°C with the baseplate installed.
However, thermal self-protection occurs near +110°C, and there is a temperature
gradient between the hotspot and the baseplate. Therefore, +100°C is recom-
mended to avoid thermal shutdown.
(14) The converter is guaranteed to turn off at the UV shutdown voltage.
(15) At full power, the package temperature of all on-board components must not exceed
+128°C.
ABSOLUTE MAXIMUM RATINGS
Removal of Soldered UVQs from Printed Circuit Boards
Should removal of the UVQ from its soldered connection be needed, thoroughly
de-solder the pins using solder wicks or de-soldering tools. At no time should
any prying or leverage be used to remove boards that have not been properly
de-soldered fi rst.
Input Source Impedance
UVQ converters must be driven from a low ac-impedance input 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 UVQ Series are tested/specifi ed for input ripple current (also
called input refl ected ripple current) and output noise using the circuits and
layout shown in Figures 2 and 3.
Figure 2. Measuring Input Ripple Current
CINVIN CBUS
LBUS
CIN = 33µF, ESR < 700m @ 100kHz
CBUS = 220µF, ESR < 100m @ 100kHz
LBUS = 12µH
3
1
+VIN
–VIN
CURRENT
PROBE
TO
OSCILLOSCOPE
+
–
External input capacitors (CIN in Figure 2) serve primarily as energy-storage
elements. They should be selected for bulk capacitance (at appropriate fre-
quencies), 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 gura-
tion may necessitate additional considerations.
TECHNICAL NOTES
MDC_UVQ Models.C03 Page 19 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
www.murata-ps.com/support
Figure 3. Measuring Output Ripple/Noise (PARD)
C1
C1 = 1μF
C2 = 10μF
LOAD 2-3 INCHES (51-76mm) FROM MODULE
C2 R
LOAD
7
8
4
5
SCOPE
+VOUT
–VOUT
+SENSE
–SENSE
In critical applications, output ripple/noise (also referred to as periodic and
random deviations or PARD) can be reduced below specifi ed limits using fi lter-
ing techniques, the simplest of which is the installation of additional external
output capacitors. Output capacitors 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 be taken into consideration. OS-CONTM organic
semiconductor capacitors (www.sanyo.com) can be especially effective for
further reduction of ripple/noise. 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.
Start-Up Threshold and Undervoltage Shutdown
Under normal start-up conditions, the UVQ Series will not begin to regulate
properly until the ramping input voltage exceeds the Start-Up Threshold.
Once operating, devices will turn off when the applied voltage drops below
the Undervoltage Shutdown point. Devices will remain off as long as the
undervoltage condition continues. Units will automatically re-start when the
applied voltage is brought back above the Start-Up Threshold. The hysteresis
built into this function avoids an indeterminate on/off condition at a single input
voltage. See Performance/Functional Specifi cations table for actual limits.
Start-Up Time
The VIN to VOUT Start-Up Time is the interval between the point at which a
ramping input voltage crosses the Start-Up Threshold voltage and the point at
which the fully loaded output voltage enters and remains within its specifi ed
1% accuracy band. Actual measured times will vary with input source imped-
ance, external input capacitance, and the slew rate and fi nal value of the input
voltage as it appears to the converter. The On/Off to VOUT start-up time assumes
that the converter is turned off via the Remote On/Off Control with the nominal
input voltage already applied.
On/Off Control
The primary-side, Remote On/Off Control function (pin 2) can be specifi ed to
operate with either positive or negative logic. Positive-logic devices ("P"suffi x)
are enabled when pin 2 is left open or is pulled high. Positive-logic devices are
disabled when pin 2 is pulled low. Negative-logic devices are off when pin 2 is
high/open and on when pin 2 is pulled low. See Figure 4.
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 current
(see Performance Specifi cations) when activated and withstand appropriate
voltage when deactivated.
Current Limiting (Power limit with current mode control)
As power demand increases on the output and enters the specifi ed “limit
inception range” (current in voltage mode and power in current mode) limiting
circuitry activates in the DC-DC converter to limit/restrict the maximum current
or total power available. In voltage mode, current limit can have a “constant or
foldback” characteristic. In current mode, once the current reaches a certain
range the output voltage will start to decrease while the output current con-
tinues to increase, thereby maintaining constant power, until a maximum peak
current is reached and the converter enters a “hic-up” (on off cycling) mode of
operation until the load is reduced below the threshold level, whereupon it will
return to a normal mode of operation. Current limit inception is defi ned as the
point where the output voltage has decreased by a pre-specifi ed percentage
(usually a 2% decrease from nominal).
Short Circuit Condition (Current mode control)
The short circuit condition is an extension of the “Current Limiting” condition.
When the monitored peak current signal reaches a certain range, the PWM
controller’s outputs are shut off thereby turning the converter “off.” This is
followed by an extended time out period. This period can vary depending on
other conditions such as the input voltage level. Following this time out period,
the PWM controller will attempt to re-start the converter by initiating a “normal
start cycle” which includes softstart. If the “fault condition” persists, another
“hic-up” cycle is initiated. This “cycle” can and will continue indefi nitely until
such time as the “fault condition” is removed, at which time the converter
will resume “normal operation.” Operating in the “hic-up” mode during a fault
condition is advantageous in that average input and output power levels are
held low preventing excessive internal increases in temperature.
2
1
3 +Vcc
REF
+ VIN EQUIVALENT CIRCUIT FOR
POSITIVE AND NEGATIVE
LOGIC MODELS
CONTROL
–VIN
O N /O F F
C O N TR O L
COMMON
Figure 4. Driving the Remote On/Off Control Pin
MDC_UVQ Models.C03 Page 20 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
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LOAD
RTRIM UP
+VOUT
–VIN
+VIN
ON/OFF
CONTROL TRIM
+SENSE
–VOUT
–SENSE
4
5
1
3
6
8
7
2
Figure 5. Trim Connections To Increase Output Voltages Using Fixed Resistors
LOAD
RTRIM DOWN
+VOUT
–VIN
+VIN
ON/OFF
CONTROL TRIM
+SENSE
–VOUT
–SENSE
4
5
1
3
6
8
7
2
Figure 6. Trim Connections To Decrease Output Voltages Using Fixed Resistors
Thermal Shutdown
UVQ converters are equipped with thermal-shutdown circuitry. If the inter-
nal temperature of the DC/DC converter rises above the designed operating
temperature (See Performance Specifi cations), 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.
Output Overvoltage Protection
The output voltage is monitored for an overvoltage condition via magnetic cou-
pling to the primary side. If the output voltage rises to a fault condition, which
could be damaging to the load circuitry (see Performance Specifi cations), the
sensing circuitry will power down the PWM controller causing the output volt-
age 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 voltages again climb to excessive levels, the overvoltage
circuitry will initiate another shutdown cycle. This on/off cycling is referred to
as "hiccup" mode.
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 the source is not current limited or the circuit appropriately fused, it
could cause permanent damage to the converter.
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 a sustained, non-current-limited, input-voltage polarity
reversal exists. For Murata Power Solutions' UVQ Series DC/DC Converters,
fast-blow fuses are recommended with values no greater than twice the
maximum input current.
Trimming Output Voltage
UVQ converters have a trim capability (pin 6) that enables users to adjust the
output voltage from +10% to –20% (refer to the trim equations). Adjustments
to the output voltage can be accomplished with a single fi xed resistor as shown
in Figures 5 and 6. 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.
On UVQs, 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
voltage 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 UVQ'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 environments.
Soldering Guidelines
Murata Power Solutions recommends the specifi cations below when installing these
converters. These specifi cations vary depending on the solder type. Exceeding these
specifi cations may cause damage to the product. Your production environment may dif-
fer; therefore please thoroughly review these guidelines with your process engineers.
Wave Solder Operations for through-hole mounted products (THMT)
For Sn/Ag/Cu based solders:
Maximum Preheat Temperature 115° C.
Maximum Pot Temperature 270° C.
Maximum Solder Dwell Time 7 seconds
For Sn/Pb based solders:
Maximum Preheat Temperature 105° C.
Maximum Pot Temperature 250° C.
Maximum Solder Dwell Time 6 seconds
MDC_UVQ Models.C03 Page 21 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
www.murata-ps.com/support
Note: Higher output 24V and 48V converters require larger, low-tempco,
precision trim resistors. An alternative is a low-TC multi-turn potentiometer
(20k typical) connected between +VOUT and –VOUT with the wiper to the Trim
pin.
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
overvoltage 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
LOAD
+VOUT
–VIN
Sense Current
Contact and PCB resistance
losses due to IR drops
Contact and PCB resistance
losses due to IR drops
Sense Return
+VIN
ON/OFF
CONTROL TRIM
+SENSE
–VOUT
–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 must connect the +Sense to +VOUT and -Sense to –VOUT at the DC/DC
converter pins.
UVQ series converters employ a sense feature to provide point of use regu-
lation, 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 applica-
tions, twisted pair or other techniques should be implemented.
UVQ 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 8. Remote Sense Circuit Confi guration
FEATURES AND OPTIONS
UP VO – 3.3
RT (k) =–10.2
13.3(VO – 1.226)
3.3 – VO
RT (k) =–10.2
16.31
DOWN
UP VO – 5
RT (k) =–10.2
20.4(VO – 1.226)
5 – VO
RT (k) =–10.2
25.01
DOWN
UP VO – 12
RT (k) =–10.2
49.6(VO – 1.226)
12 – VO
RT (k) =–10.2
60.45
DOWN
UP VO – 15
RT (k) =–10.2
62.9(VO – 1.226)
15 – VO
RT (k) =–10.2
76.56
DOWN
UP VO – 18
RT (k) =–10.2
75.5(VO – 1.226)
18 – VO
RT (k) =–10.2
92.9
DOWN
UVQ-3.3/35-D48
UVQ-5/25-D24, UVQ-5/20-D48
UVQ-12/8-D24, -12/10-D48
UVQ-15/7-D24, -D48
UVQ-18/5.6-D24, -18/6-D48
UP VO – 2.5
RT (k) =–10.2
10(VO – 1.226)
2.5 – VO
RT (k) =–10.2
12.26
DOWN
UVQ-2.5/40-D48, UVQ-2.5/35-D24
UVQ-1.5/40-D24
UP VO – 1.5
RT (k) = –10.2
6.23(VO – 1.226)
1.5 – VO
RT (k) = –10.2
7.64
DOWN
101(VO – 1.226)
UP VO – 24
RT (k) = –10.2 24 – VO
RT (k) = –10.2
124.2
DOWN
UVQ-24/4.5-D24, -D48
210.75(VO – 1.226)
UP VO – 48
RT (k) = –10.2 48 – VO
RT (k) = –10.2
250
DOWN
UVQ-48/2.5-D24, -D48
Trim Up Trim Down
Trim Equations
MDC_UVQ Models.C03 Page 22 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
www.murata-ps.com/support
Figure 7. Model UVQ Heatsink Assembly Diagram
UVQ Series Aluminum Heatsink
The UVQ series converter baseplate can be attached either to an enclosure wall
or a heatsink to remove heat from internal power dissipation. The discus-
sion below concerns only the heatsink alternative. The UVQs are available
with a low-profi le extruded aluminum heatsink kit, models HS-QB25-UVQ,
HS-QB50-UVQ, and HS-QB100-UVQ. This kit includes the heatsink, thermal
mounting pad, screws and mounting hardware. See the assembly diagram
below. Do not overtighten the screws in the tapped holes in the converter (3.5
n-m or 1.9 in-oz. max.). This kit adds excellent thermal performance without
sacrifi cing too much component height. See the Mechanical Outline Drawings
for assembled dimensions. If the thermal pad is fi rmly attached, no thermal
compound (“thermal grease”) is required.
Thermal Performance
The HS-QB25-UVQ heatsink has a thermal resistance of 12 °C/Watt of internal
heat dissipation with “natural convection” airfl ow (no fans or other mechanical
airfl ow) at sea level altitude. This thermal resistance assumes that the heatsink
is fi rmly attached using the supplied thermal pad and that there is no nearby
wall or enclosure surface to inhibit the airfl ow. The thermal pad adds a negli-
gible series resistance of approximately 0.5°C/Watt so that the total assembled
resistance is 12.5°C/Watt.
Be aware that we need to handle only the internal heat dissipation, not the
full power output of the converter. This internal heat dissipation is related to the
effi ciency as follows:
Power Dissipation [Pd] = Power In – Power Out [1]
Power Out / Power In = Effi ciency [in %] / 100 [2]
Power Dissipation [Pd] = Power In x (1 –Effi ciency%/100) [3]
Power Dissipation [Pd] = Power Out x (1 / (Effi ciency%/100) - 1) [4]
Effi ciency of course varies with input voltage and the total output power.
Please refer to the Performance Curves.
Since many applications do include fans, here is an approximate equation to
calculate the net thermal resistance:
R [at airfl ow] = R [natural convection] / (1 + (Airfl ow in LFM) x
[Airfl ow Constant]) [5]
Where,
R [at airfl ow] is the net thermal resistance (in °C/W) with the amount of
airfl ow available and,
R [natural convection] is the still air total path thermal resistance or in this
case 12.5°C/Watt and,
“Airfl ow in LFM” is the net air movement fl ow rate immediately at the converter.
This equation simplifi es an otherwise complex aerodynamic model but is a
useful starting point. The “Airfl ow Constant” is dependent on the fan and enclo-
sure geometry. For example, if 200 LFM of airfl ow reduces the effective natural
convection thermal resistance by one half, the airfl ow constant would be
0.005. There is no practical way to publish a “one size fi ts all” airfl ow constant
because of variations in airfl ow direction, heatsink orientation, adjacent walls,
enclosure geometry, etc. Each application must be determined empirically and
the equation is primarily a way to help understand the cooling arithmetic.
This equation basically says that small amounts of forced airfl ow are quite
effective removing the heat. But very high airfl ows give diminishing returns.
Conversely, no forced airfl ow causes considerable heat buildup. At zero airfl ow,
cooling occurs only because of natural convection over the heatsink. Natural
convection is often well below 50 LFM, not much of a breeze.
While these equations are useful as a conceptual aid, most users fi nd it
very diffi cult to measure actual airfl ow rates at the converter. Even if you know
the velocity specifi cations of the fan, this does not usually relate directly to
the enclosure geometry. Be sure to use a considerable safety margin doing
thermal analysis. If in doubt, measure the actual heat sink temperature with
a calibrated thermocouple, RTD or thermistor. Safe operation should keep the
heat sink below 100°C.
When assembling these kits onto the converter, include ALL kit hardware to
assure adequate mechanical capture and proper clearances. Thread relief is
0.090" (2.3mm).
MDC_UVQ Models.C03 Page 23 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
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Calculating Maximum Power Dissipation
To determine the maximum amount of internal power dissipation, fi nd the
ambient temperature inside the enclosure and the airfl ow (in Linear Feet per
Minute – LFM) at the converter. Determine the expected heat dissipation using
the Effi ciency curves and the converter Input Voltage. You should also compen-
sate for lower atmospheric pressure if your application altitude is considerably
above sea level.
The general proceedure is to compute the expected temperature rise of the
heatsink. If the heatsink exceeds +100°C. either increase the airfl ow and/or
reduce the power output. Start with this equation:
Internal Heat Dissipation [Pd in Watts] = (Ts – Ta)/R [at airfl ow] [6]
where “Ta” is the enclosure ambient air temperature and,
where “Ts” is the heatsink temperature and,
where “R [at airfl ow]” is a specifi c heat transfer thermal resistance (in
degrees Celsius per Watt) for a particular heat sink at a set airfl ow rate. We
have already estimated R [at airfl ow] in the equations above.
Note particularly that Ta is the air temperature inside the enclosure at the
heatsink, not the outside air temperature. Most enclosures have higher internal
temperatures, especially if the converter is “downwind” from other heat-pro-
ducing circuits. Note also that this “Pd” term is only the internal heat dissipated
inside the converter and not the total power output of the converter.
We can rearrange this equation to give an estimated temperature rise of the
heatsink as follows:
Ts = (Pd x R [at airfl ow]) + Ta [7]
Heatsink Kit *
Model Number
Still Air (Natural convection)
thermal resistance
Heatsink height
(see drawing)
HS-QB25-UVQ 12°C/Watt 0.25" (6.35mm)
HS-QB50-UVQ 10.6°C/Watt 0.50" (12.7mm)
HS-QB100-UVQ 8°C/Watt 1.00" (25.4mm)
* Kit includes heatsink, thermal pad and mounting hardware. These are
non-RoHS models. For RoHS-6 versions, add “-C” to the model number
(e.g., HS-QB25-UVQ-C).
Heat Sink Example
Assume an effi ciency of 92% and power output of 100 Watts. Using equation
[4], Pd is about 8.7 Watts at an input voltage of 48 Volts. Using +30°C ambient
temperature inside the enclosure, we wish to limit the heat sink temperature to
+90°C maximum baseplate temperature to stay well away from thermal shut-
down. The +90°C. fi gure also allows some margin in case the ambient climbs
above +30°C or the input voltage varies, giving us less than 92% effi ciency.
The heat sink and airfl ow combination must have the following characteristics:
8.7 W = (90-30) / R[airfl ow] or,
R[airfl ow] = 60/8.7 = 6.9°C/W
Since the ambient thermal resistance of the heatsink and pad is 12.5°C/W,
we need additional forced cooling to get us down to 6.9°C/W. Using a hypo-
thetical airfl ow constant of 0.005, we can rearrange equation [5] as follows:
(Required Airfl ow, LFM) x (Airfl ow Constant) = R[Nat.Convection] /
R[at airfl ow] –1
or, (Required Airfl ow, LFM) x (Airfl ow Constant) = 12.5/6.9 –1 = 0.81 and,
rearranging again,
(Required Airfl ow, LFM) = 0.81/0.005 = 162 LFM
162 LFM is the minumum airfl ow to keep the heatsink below +90°C.
Increase the airfl ow to several hundred LFM to reduce the heatsink tempera-
ture further and improve life and reliability.
MDC_UVQ Models.C03 Page 24 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
0.10
(2.54)
*
* UVQ SERIES HEATSINKS ARE AVAILABLE IN 3 HEIGHTS:
0.25 (6.35), 0.50 (12.70) AND 1.00 (25.4)
1.45
(36.83)
2.28
(57.91)
MATERIAL: BLACK ANODIZED ALUMINUM
1.03
(26.16)
1.860
(47.24)
0.140 DIA. (3.56) (4 PLACES)
Dimensions in inches (mm)
www.murata-ps.com/support
MDC_UVQ Models.C03 Page 25 of 25
UVQ Series
Low Profi le, Isolated Quarter Brick
2.5–40 Amp DC/DC Converters
Figure 9. Vertical Wind Tunnel
IR Video
Camera
IR Transparent
optical window Variable
speed fan
Heating
element
Ambient
temperature
sensor
Airflow
collimator
Precision
low-rate
anemometer
3” below UUT
Unit under
test (UUT)
Vertical Wind Tunnel
Murata Power Solutions employs a computer controlled
custom-designed closed loop vertical wind tunnel, infrared
video camera system, and test instrumentation for accurate
airfl ow and heat dissipation analysis of power products.
The system includes a precision low fl ow-rate anemometer,
variable speed fan, power supply input and load controls,
temperature gauges, and adjustable heating element.
The IR camera monitors the thermal performance of the
Unit Under Test (UUT) under static steady-state conditions. A
special optical port is used which is transparent to infrared
wavelengths.
Both through-hole and surface mount converters are
soldered down to a host carrier board for realistic heat
absorption and spreading. Both longitudinal and transverse
airfl ow studies are possible by rotation of this carrier board
since there are often signifi cant differences in the heat
dissipation in the two airfl ow directions. The combination of
adjustable airfl ow, adjustable ambient heat, and adjustable
Input/Output currents and voltages mean that a very wide
range of measurement conditions can be studied.
The collimator reduces the amount of turbulence adjacent
to the UUT by minimizing airfl ow turbulence. Such turbu-
lence infl uences the effective heat transfer characteristics
and gives false readings. Excess turbulence removes more
heat from some surfaces and less heat from others, possibly
causing uneven overheating.
Both sides of the UUT are studied since there are different
thermal gradients on each side. The adjustable heating element
and fan, built-in temperature gauges, and no-contact IR camera mean
that power supplies are tested in real-world conditions.
www.murata-ps.com/support
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. © 2012 Murata Power Solutions, Inc.
Murata Power Solutions, Inc.
11 Cabot Boulevard, Mansfi eld, MA 02048-1151 U.S.A.
ISO 9001 and 14001 REGISTERED
This product is subject to the following operating requirements
and the Life and Safety Critical Application Sales Policy:
Refer to: http://www.murata-ps.com/requirements/