www.murata-ps.com
UNR Series
Single Output, Non-Isolated, 1.8/2.5/3.3V
OUT
3.6-10W DC/DC Converters
PRODUCT OVERVIEW
Murata Power Solutions' 3.6-10W UNR Series
consists of non-isolated, 5V-to-1.8V (2A), 5V-to-
2.5V (2A), 5V-to-3.3V (3A), and 12V-to-3.3V (3A)
DC/DC converters in miniature surface-mount
and through-hole packages. The "gull-wing" SMT
packages (with metal shells and non-conductive
plastic baseplates) weigh a mere 17 grams and
can withstand lead temperatures up to +230°C.
They are compatible with virtually all contemporary
pick-and-place and solder-reflow processes.
The true benefits of distributed power will
ultimately be realized only when every low-voltage,
high-current CPLD, ASIC, DSP, etc. has its own
"power plant" right next to it. With isolated DC/
DC converters inevitably residing at the edges of
boards in proximity with backplanes and power
buses, the "on-board" proliferation of distributed
power will continue with more cost-effective,
non-isolated devices. The low-cost, easy-to-use
(no external components required), highly reliable
(100% fully automated SMT construction) 3.6-10W
UNR Series makes this power processing at the
concluding point of use a practical reality today.
These versatile DC/DC's are fully line and load
regulated. They feature user-optional on/off control
(for power-sequencing requirements), output cur-
rent limiting, and short-circuit protection (foldback
technique with auto-recovery). Additionally, the
12V-to-3.3V models offer input undervoltage
lockout (at 9.6V). Their impressive guaranteed
efficiencies enable all models to deliver their fully
rated output power from –40 to +65/70°C (ambi-
ent) without heat sinking or forced-air cooling.
If you've already considered and rejected the
use of inefficient, step-down, linear regulators,
take a look at one of these new switching buck
regulators. Their high efficiency, ease-of-use, long-
term reliability, and overall cost effectiveness will
impress you. Safety agency approvals are currently
in progress.
FEATURES
Low cost! High reliability!
1" x 1" through-hole package or 1.01" x 1.01"
SMT package
Gull-wing leads; Standard reflow
Complete; No external components
Outputs: 1.8V/2A, 2.5V/2A, 3.3V/3A
Inputs: 4.75-5.5V, 10.8-13.6V
Guaranteed efficiencies to 87%
Output noise as low as 40mVp-p
Transient response as quick as 20μsec
–40 to +70°C operation with no derating
On/off control; EMC compliant
IEC950/EN60950/UL1950 approvals
Modifications and customs for OEM's
+V
IN
+V
OUT
➁
INPUT
RETURN
OUTPUT
RETURN
➀
LOGIC
GROUND
UNDERVOLTAGE
SHUTDOWN
ON/OFF
CONTROL
PWM
CONTROLLER
CURRENT LIMITING
& S.C. SHUTDOWN
REFERENCE &
ERROR AMP
Figure 1. Simplified Schematic
Typical topology is shown.
➀
"D5" models do not have input undervoltage shutdown.
➁
"D5" models employ a more traditional buck-regulator design
in which this FET is replaced with a power Schottky diode.
For full details go to
www.murata-ps.com/rohs
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email: sales@murata-ps.com
04 Nov 2010 MDC_UNR 3.6-10W_B02
Page 1 of 8
UNR Series
Single Output, Non-Isolated, 1.8/2.5/3.3V
OUT
3.6-10W DC/DC Converters
PERFORMANCE SPECIFICATIONS AND ORDERING GUIDE
Part Number
➅
Power
Vout (V)
1.8
1.8
2.5
2.5
3.3
3.3
3.3
3.3
Iout
(A)
2
2
2
2
3
3
3
3
Output
R/N (mVp-p)
➁
Regulation (Max.)
Typ.
35
35
40
40
40
40
100
100
Input
Range
(V)
4.75-5.5
4.75-5.5
4.75-5.5
4.75-5.5
4.75-5.5
4.75-5.5
10.8-13.6
10.8-13.6
Efficiency
I
IN
➃
(mA/A)
30/0.91
30/0.91
200/5.62
200/5.62
40/2.25
40/2.25
40/0.93
40/0.93
(W)
3.6
3.6
5
5
9.9
9.9
9.9
9.9
Max.
50
50
80
80
75
75
150
150
Line
±0.35%
±0.35%
±0.1%
±0.1%
±0.4%
±0.4%
±0.25%
±0.25%
V
IN
Nom.
(V)
Load
➂
±0.5%
±0.5%
±0.5%
±0.5%
±0.5%
±0.5%
±0.5%
±0.5%
5
5
5
5
5
5
12
12
Min.
77%
77%
85%
85%
86%
86%
87%
87%
Typ.
79%
79%
89%
89%
88%
88%
89%
89%
Package
(Case
Pinout)
C7A, P9
C17, P24
C7A, P9
C17, P24
C7A, P9
C17, P24
C7A, P9
C17, P24
UNR-1.8/2-D5
UNR-1.8/2-D5SM
UNR-2.5/2-D5
UNR-2.5/2-D5SM
UNR-3.3/3-D5
UNR-3.3/3-D5SM
UNR-3.3/3-D12
➁
UNR-3.3/3-D12SM
➁
➀
Typical at T
A
= +25°C under nominal line voltage and full-load conditions, unless otherwise noted.
The UNR-1.8/2-D5 and D5SM models require an external 15k: pull-up resistor between +Input
and On/Off Control for normal operation. See On/Off Control for details.
➁
Ripple/Noise (R/N) measured over a 20MHz bandwidth. The UNR-3.3/3-D12 and D12SM models
are specified with an external 22μF input capacitor. All other models are specified with no external
I/O capacitors. Output noise on the D12 models can be reduced significantly with the addition of
external output capacitors. See I/O Filtering.
➂
D5/D5SM models require a minimum 300mA load current to maintain regulation. D12/D12SM
models have no mimimum load requirement. Listed specs apply from 300mA to full load for D5/
D5SM models and from no load to full load for D12/D12SM models.
➃
Nominal line voltage, no-load/full-load conditions.
➄
D5/D5SM models may experience start-up problems if voltages greater than 1.0V (for 3.3V models)
or 1.2V (for 1.8/2.5V models) are present across the output pins during power-up.
➅
These are only partial part numbers. Refer to the part number structure when ordering.
PART NUMBER STRUCTURE
U NR
-
2.5
/
2
-
D5 SM
-
C
Output Configuration:
U
= Unipolar
Non-Isolated
Nominal Output Voltage:
1.8, 2.5 or 3.3 Volts
Maximum Output Current
in Amps
RoHS-6 compliant
Surface-Mount Packaging
Input Voltage Range:
D5
= 4.75-5.5 Volts (5V nominal)
D12
= 10.8-13.6 Volts (12V nominal)
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04 Nov 2010 MDC_UNR 3.6-10W_B02
Page 2 of 8
UNR Series
Single Output, Non-Isolated, 1.8/2.5/3.3V
OUT
3.6-10W DC/DC Converters
MECHANICAL SPECIFICATIONS
THROUGH-HOLE MOUNT
1.00 ±0.02
(25.40)
STANDOFFS
0.020
(0.51)
SURFACE MOUNT
0.100
(2.54)
4
3
0.500
(12.70)
2
0.300
(7.62)
1
TOP VIEW
6
5
0.10
(2.54)
1.22
(30.99)
9
8
7
0.800
(20.32)
1.01
±0.02
4 EQ. SP.@
(25.65
±0.51)
0.200 (5.08)
0.45 ±0.02
(11.43 ±0.51)
Case C7A
0.20 MIN
(5.08)
0.040 ±0.002 DIA.
(1.016 ±0.051)
0.800
(20.32)
0.10
(2.54)
Case C17
0.100
(2.54)
1
4
2
5
0.200
(5.08)
6
3
0.400
(10.16)
0.800 1.00 ±0.02
(20.32) (25.40)
1.01
±0.02
(25.65
±0.51)
0.110
(2.79)
0.060
(1.52)
0.020
(0.51)
0.49
±0.02
(12.45
±0.51)
BOTTOM VIEW
0.200
(5.08)
0.10
(2.54)
INSULATED BASE
METAL CASE
PLASTIC CASE WITH AN INSULATED BASE
0.015
(0.38)
0.055
(1.40)
SEE SPECIAL SMT SOLDER INSTRUCTIONS ON PAGE 6
Dimensions are in inches (mm shown for ref. only).
INPUT/OUTPUT CONNECTIONS
Third Angle Projection
Pin
1
2
3
4
Function P9
Logic Ground
On/Off Control
+Output
Output Return
Input Return
+Input
No Pin
No Pin
No Pin
Function P24
N.C.
Logic Ground
On/Off Control
N.C.
+Output
N.C.
Output Return
Input Return
+Input
Tolerances (unless otherwise specified):
.XX ± 0.02 (0.5)
.XXX ± 0.010 (0.25)
Angles ± 2˚
Components are shown for reference only.
5
6
7
8
9
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04 Nov 2010 MDC_UNR 3.6-10W_B02
Page 3 of 8
UNR Series
Performance/Functional Specifications
Single Output, Non-Isolated, 1.8/2.5/3.3V
OUT
3.6-10W DC/DC Converters
Typical @ T
A
= +25°C under nominal line voltage and full-load conditions with no external filtering.
Specifications apply to both surface-mount and through-hole models, unless noted.
➀ ➆
Input
Input Voltage Range:
D5 Models
D12 Models
Overvoltage Shutdown
Start-Up Threshold:
D12 Models
➁
Undervoltage Shutdown:
D12 Models
➁
Input Current:
Normal Operating Conditions
Standby Mode (Off or undervoltage):
1.8V
OUT
2.5V
OUT
, 3.3V
OUT
D5 Models
3.3V
OUT
D12 Models
Output Short-Circuit Condition
Input Ripple Current:
1.8V
OUT
, 3.3V
OUT
D12 Models
2.5V
OUT
, 3.3V
OUT
D5 Models
Input Filter Type
Reverse-Polarity Protection
On/Off Control
➂
4.75-5.5 Volts (5V nominal)
10.8-13.6 Volts (12V nominal)
None
10.2V typical, 10.8V maximum
9.6V typical, 8.2V minimum
See Ordering Guide
20mA typical, 30mA maximum
11mA typical, 20mA maximum
5mA typical, 10mA maximum
50mArms
50mAp-p
150mAp-p
Capacitive
None, install external fuse
TTL high (or open) = on, low = off
1.5V typical logic threshold
Through Hole Package
Pin Material:
RoHS:
Non-RoHS
Weight
Dimensions:
Surface Mount Package
Through Hole Package
Shielding:
Surface Mount Package
Through Hole Package
Case Connection
(Surface Mount)
Case Material:
Surface Mount Package
Physical
.
1.01"x1.01"x0.49" (25.65x25.65x12.45mm) nom.
1.00"x1.00"x0.45" (25.40x25.40x11.43mm) nom.
5-sided
None
Input/output return
Corrosion-resistant steel with
non-conductive, epoxy-based, black
enamel finish and plastic baseplate
Diallyl phthalate, UL94V-0 rated
Gold plate over copper alloy
Tin over copper alloy
0.6 ounces (17 grams)
Output
V
OUT
Accuracy
(50% load):
1.8V
OUT
Models
2.5V
OUT
Models
3.3V
OUT
D5 Models
3.3V
OUT
D12 Models
Temperature Coefficient
Ripple/Noise
(20MHz BW)
➃
Line/Load Regulation
Efficiency
Current Limiting
➄
Transient Response
(50% load step):
1.8V
OUT
Models
2.5V
OUT
, 3.3V
OUT
D12 Models
3.3V
OUT
D5 Models
Start-Up Time:
➅ ➆
V
IN
to V
OUT
: D5 Models
D12 Models
On/Off to V
OUT
: D5 Models
D12 Models
Switching Frequency
Operating Temperature
(Ambient):
Without Derating
With Derating
Storage Temperature
Flammability
±1.75% (±32mV) maximum
±1.75% (±44mV) maximum
±1.5% (±50mV) maximum
±1% (±33mV) maximum
±0.02% per °C
See Ordering Guide
See Ordering Guide
See Ordering Guide
Auto-recovery
➀
D5 models require a minimum 300mA load current to maintain specified regulation. D12
models have no minimum load requirement. Operating D5 models under no-load conditions
will not damage these devices, however they may not meet all listed specifications. The UNR-
1.8/2-D5 and D5SM require an external 15: pull-up resistor between +Input and On/Off
Control for normal operation. See On/Off Control for details. The UNR-3.3/3-D12 and D12SM
are specifiied with an external 22μF input capacitor. See I/O Filtering for details.
➁
See Startup Threshold and Undervoltage Shutdown for details.
➂
See On/Off Control for details.
➃
The 22μF external input capacitor required for the UNR-3.3/3-D12 and D12SM should be
minimally rated for 1.5Arms ripple current and 125m: ESR. Output noise for all models can
be further reduced with the installation of external output capacitors. See I/O Filtering for
details.
➄
Current limiting initiates at approximately 30% above rated load. Under short-circuit
conditions, output current folds back to approximately 150mA and input current drops to
approximtely 50mA. Both remain at those levels until the short is removed.
➅
See Start-Up Time for details.
➆
D5/D5SM models may experience start-up problems if voltages greater than 1.0V (for 3.3V
models) or 1.2V (for 1.8/2.5V models) are present across the output pins during power-up.
Dynamic Characteristics
Absolute Maximum Ratings
20μsec to ±1% of final value
30μsec to ±1% of final value
40μsec to ±1% of final value
100msec typical, 120msec maximum
13msec typical, 20msec maximum
60msec typical, 120msec maximum
13msec typical, 20msec maximum
200kHz (±30kHz)
Input Voltage:
Continuous:
D5 Models
D12 Models
Transient (100msec):
D5 Models
D12 Models
Input Reverse-Polarity Protection
Output Overvoltage Protection
Output Current
7 Volts
15 Volts
15 Volts
24 Volts
None, install external fuse
None
Current limited. Devices can
withstand a sustained output
short circuit without damage.
–40 to +105°C
+300°C
+230°C
Environmental
–40 to +65/70°C
to +100°C (See Derating Curves)
–40 to +105°C
UL 94V-0
Storage Temperature
Lead Temperature
Selective soldering (10 sec.)
Reflow soldering (75 sec.)
These 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/Functional Specifications Table is not implied.
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04 Nov 2010 MDC_UNR 3.6-10W_B02
Page 4 of 8
UNR Series
Single Output, Non-Isolated, 1.8/2.5/3.3V
OUT
3.6-10W DC/DC Converters
TEMPERATURE DERATING
10
9
8
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 Murata Power Solutions UNR Series 3.6-10
Watt DC/DC Converters, you should use slow-blow type fuses with values
no greater than the following.
Model Number
Fuse Value
UNR-1.8/2-D5/-D5SM
1.5 Amps
UNR-2.5/2-D5/-D5SM
2 Amps
UNR-3.3/3-D5/-D5SM
3 Amps
UNR-3.3/3-D12/-D12SM
1.5 Amps
Start-Up Threshold and Undervoltage Shutdown
(UNR-3.3/3-D12 and D12SM only)
UNR-3.3/3-D5
UNR-3.3/3-D5SM
UNR-3.3/3-D12
UNR-3.3/3-D12SM
Output Power (Watts)
7
6
5
4
3
2
1
0
–40
UNR-2.5/2-D5
UNR-2.5/2-D5SM
UNR-1.8/2-D5
UNR-1.8/2-D5SM
0
40
45
50
55
60
65
70
75
80
85
90
95
100
Ambient Temperature (˚C)
TECHNICAL NOTES
I/O Filtering and Noise Reduction
All D5 models of UNR 3.6-10W Series DC/DC converters achieve their
rated ripple and noise specifications without the use of external input/
output capacitors. The UNR-3.3/3-D12 and D12SM models are tested and
specified with a single, external 22μF input capacitor (minimally rated for
1.5Arms ripple current and 120m: ESR).
In critical applications, input/output ripple/noise may be further reduced
by installing additional external I/O caps. Input capacitors, which function
primarily as energy-storage elements, should be selected for bulk capaci-
tance, low ESR and high rms-ripple-current ratings. Output capacitors,
which function more as true filter elements, should be selected for bulk
capacitance, low ESR, and appropriate frequency response. All caps should
have appropriate voltage ratings and be mounted as close to the convert-
ers as possible. Temperature variations for all parameters should obviously
be taken into consideration.
The most effective combination of external I/O capacitors will be a func-
tion of your line voltage and source impedance, as well as your particular
load and layout conditions. Our Applications Engineers will be happy to
recommend potential solutions and can discuss the possibility of our modi-
fying a given device’s internal filtering to meet your specific requirements.
Contact our Applications Engineering Group for additional details.
Return Current Paths
The Input Return, Output Return and Logic Ground are all connected to
each other internal to each device. To the extent possible, all load current
should be returned through the Output Return (via low-impedance runs)
and all input current returned through the Input Return. Any control signals
applied to the On/Off Control pin should be referenced to Logic Ground. The
internal trace leading to Logic Ground is not designed to carry high current.
Devices should never be installed in a manner that results in high current
flow through Logic Ground (i.e., the Input/Output Returns should never be
left open or attached via high-impedance connections).
Under normal start-up conditions, UNR-3.3/3-D12 and D12SM devices
will not begin to regulate until the ramping input voltage exceeds the Start-
Up Threshold Voltage (typically 10.2V). Once operating, devices will not turn
off until the input voltage drops below the Undervoltage Shutdown/Lockout
limit (typically 9.6V). Subsequent re-start will not occur until the input is
brought back up to the Start-Up Threshold. This built-in hysteresis obviously
avoids any indeterminate on/off conditions at a single voltage.
Start-Up Time
For the three D5 models (that do not have an input turn-on threshold),
the V
IN
to V
OUT
Start-Up Time is the interval between the time a step input
is applied to the device and the fully loaded output voltage enters and
remains within its specified accuracy band.
For the UNR-3.3/3-D12 and D12SM, V
IN
to V
OUT
Start-Up Time is the
interval between the time at which a rapidly ramping input voltage crosses
the turn-on threshold point and the fully loaded output voltage enters and
remains within its specified accuracy band. Actual measured times will vary
with input source impedance, external input capacitance, and the slew rate
and final value of the input voltage as it appears to the converter.
The On/Off to V
OUT
Start-Up Time assumes the converter is turned off via
the On/Off Control with the nominal input voltage already applied to the
converter. The specification defines the interval between the time at which
the converter is turned on and the fully loaded output voltage enters and
remains within its specified accuracy band.
Internal circuit design of the 3.3V
OUT
models mandates that no voltages
greater than 1.0V be present on the output pins at power-up. 1.8V
OUT
and
2.5V
OUT
models can not have voltages greater than 1.2V present on their
output pins at power-up. Failure to comply may result in start-up problems.
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04 Nov 2010 MDC_UNR 3.6-10W_B02
Page 5 of 8
Microchip MCU
