UNR-2.5/2-D5-C Murata Power Solutions Inc, UNR-2.5/2-D5-C Datasheet - Page 5

• Manufacturer Part Number: UNR-2.5/2-D5-C
• Description: DC/DC TH 2A 5-2.5V Non-Iso
• Manufacturer: Murata Power Solutions Inc

Specifications of UNR-2.5/2-D5-C

• Product: Non-Isolated / POL
• Output Power: 5 W
• Input Voltage Range: 4.75 V to 5.5 V
• Number Of Outputs: 1
• Output Voltage (channel 1): 2.5 V
• Output Current (channel 1): 2 A
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Return Current Paths
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
fl ow through Logic Ground (i.e., the Input/Output Returns should never be
left open or attached via high-impedance connections).
I/O Filtering and Noise Reduction
rated ripple and noise specifi cations without the use of external input/
output capacitors. The UNR-3.3/3-D12 and D12SM models are tested and
specifi ed with a single, external 22μF input capacitor (minimally rated for
1.5Arms ripple current and 120m: ESR).
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 fi lter 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.
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 fi ltering to meet your specifi c requirements.
Contact our Applications Engineering Group for additional details.
The Input Return, Output Return and Logic Ground are all connected to
All D5 models of UNR 3.6-10W Series DC/DC converters achieve their
In critical applications, input/output ripple/noise may be further reduced
The most effective combination of external I/O capacitors will be a func-
10
9
8
7
6
5
4
3
2
1
0
–40
UNR-3.3/3-D5
UNR-3.3/3-D5SM
UNR-3.3/3-D12
UNR-3.3/3-D12SM
0
40
45
UNR-1.8/2-D5
UNR-1.8/2-D5SM
UNR-2.5/2-D5
UNR-2.5/2-D5SM
TEMPERATURE DERATING
50
T E C H N I C A L N O T E S
Ambient Temperature (˚C)
55
60
65
70
75
80
85
www.murata-ps.com
90
Single Output, Non-Isolated, 1.8/2.5/3.3V
95
100
Input Fusing
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.
(UNR-3.3/3-D12 and D12SM only)
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
the V
is applied to the device and the fully loaded output voltage enters and
remains within its specifi ed accuracy band.
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 specifi ed accuracy band. Actual measured times will vary
with input source impedance, external input capacitance, and the slew rate
and fi nal value of the input voltage as it appears to the converter.
the On/Off Control with the nominal input voltage already applied to the
converter. The specifi cation defi nes the interval between the time at which
the converter is turned on and the fully loaded output voltage enters and
remains within its specifi ed accuracy band.
greater than 1.0V be present on the output pins at power-up. 1.8V
2.5V
output pins at power-up. Failure to comply may result in start-up problems.
Certain applications and/or safety agencies may require the installation
Start-Up Threshold and Undervoltage Shutdown
Under normal start-up conditions, UNR-3.3/3-D12 and D12SM devices
For the three D5 models (that do not have an input turn-on threshold),
For the UNR-3.3/3-D12 and D12SM, V
The On/Off to V
Internal circuit design of the 3.3V
OUT
IN
to V
models can not have voltages greater than 1.2V present on their
UNR-3.3/3-D12/-D12SM
UNR-1.8/2-D5/-D5SM
UNR-2.5/2-D5/-D5SM
UNR-3.3/3-D5/-D5SM
OUT
Model Number
Start-Up Time is the interval between the time a step input
OUT
Start-Up Time assumes the converter is turned off via
OUT
04 Nov 2010 MDC_UNR 3.6-10W_B02 Page 5 of 8
OUT
models mandates that no voltages
Fuse Value
IN
1.5 Amps
1.5 Amps
2 Amps
3 Amps
to V
3.6-10W DC/DC Converters
OUT
email: [e-mail]
UNR Series
Start-Up Time is the
OUT
and