Datasheet
Output Capacitive Load
These converters do not require external capacitance added to achieve
rated specifi cations. Users should only consider adding capacitance to reduce
switching noise and/or to handle spike current load steps. Install only enough
capacitance to achieve noise objectives. Excess external capacitance may
cause regulation problems, degraded transient response and possible oscilla-
tion or instability.
Output Voltage Adustment
The output voltage may be adjusted over a limited range by connecting an
external trim resistor (Rtrim) between the Trim pin and Ground. The Rtrim resis-
tor must be a 1/10 Watt precision metal fi lm type, ±1% accuracy or better with
low temperature coeffi cient, ±100 ppm/oC. or better. Mount the resistor close
to the converter with very short leads or use a surface mount trim resistor.
In the tables below, the calculated resistance is given. Do not exceed the
specifi ed limits of the output voltage or the converter’s maximum power rating
when applying these resistors. Also, avoid high noise at the Trim input. How-
ever, to prevent instability, you should never connect any capacitors to Trim.
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 differ therefore please thoroughly review these guidelines with your process
engineers.
Recommended Lead-free Solder Refl ow Profi le
High trace = normal upper limit
Low trace - normal lower limit
0
50
100
150
200
250
0 30 60 90 120 150 180 210 240 270 300
Time (sec)
Temperature (°C)
Preheating Zone
240 sec max
Soaking Zone
120 sec max
Reflow Zone
time above
217° C
45-75 sec
Peak Temp.
235-260° C
<1.5° C/sec
Reflow Solder Operations for surface-mount products (SMT)
For Sn/Ag/Cu based solders:
Preheat Temperature Less than 1 ºC. per second
Time over Liquidus 45 to 75 seconds
Maximum Peak Temperature 260 ºC.
Cooling Rate Less than 3 ºC. per second
For Sn/Pb based solders:
Preheat Temperature Less than 1 ºC. per second
Time over Liquidus 60 to 75 seconds
Maximum Peak Temperature 235 ºC.
Cooling Rate Less than 3 ºC. per second
RTRIM () =
_____________
– 1000
VOUT – 0.7525V
10500
Output Voltage Calculated Rtrim (KΩ)
4.5 V. 1.802
3.3 V. 3.122
2.5 V. 5.009
1.8 V. 9.024
1.5 V. 13.047
1.2 V. 22.464
1.0 V. 41.424
0.7525 V. ∞ (open)
Resistor Trim Equation:
MDC_OKI-T/3-W32 Series.A07 Page 13 of 13
OKI-T/3-W32 Series
Adjustable Output 3-Amp DOSA-SMT DC/DC Converters
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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. © 2013 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/