(1) All models are tested and specified with external 1||10 μF ceramic/tantalum output
capacitors and a 22 μF external input capacitor. All capacitors are low ESR types. These
capacitors are necessary to accommodate our test equipment and may not be required
to achieve specified performance in your applications. All models are stable and regulate
within spec under no-load conditions.
All specifications are typical unless noted. General conditions for Specifications are
+25 °C, V
IN
=nominal, V
OUT
=5V, full load. Adequate airflow must be supplied for extended
testing under power.
(2) Input Ripple Current is tested and specified over a 5 Hz to 20 MHz bandwidth. Input filter-
ing is C
IN
=2 × 100 μF, 100V tantalum, C
BUS
=1000 μF, 100V electrolytic, L
BUS
=1 μH.
(3) Note that Maximum Power Derating curves indicate an average current at nominal input
voltage. At higher temperatures and/or lower airflow, the DC/DC converter will tolerate
brief full current outputs if the total RMS current over time does not exceed the Derating
curve. All Derating curves are presented at sea level altitude. Be aware of reduced power
dissipation with increasing density altitude.
(4) Mean Time Before Failure is calculated using the Telcordia (Belcore) SR-332 Method 1,
Case 3, ground fixed conditions, Tpcboard=+25°C, full output load, natural air convec-
tion.
(5) The On/Off Control is normally controlled by a switch or open collector or open drain tran-
sistor. But it may also be driven with external logic or by applying appropriate external
voltages which are referenced to Input Common.
(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. This may damage the
outputs.
(8) Output noise may be further reduced by adding an external filter. See I/O Filtering and
Noise Reduction. Use only as much output filtering as needed
and no more.
Larger caps
may slow transient response or degrade dynamic performance. Thoroughly test your
system under full load, especially with low-ESR ceramic capacitors.
(9) All models are fully operational and meet published specifications, including “cold start” at
–40°C.
(10) Regulation specifications describe the deviation as the line input voltage or output load
current is varied from a nominal midpoint value to either extreme.
(11) For the LSS-T/10-W12, the maximum rated output power is 51 Watts (5.1 Volts and
10 Amps). Output adjustment up to 6 Volts must reduce current to remain within the
51 Watt output limit.
(12) Output current limit and short circuit protection is non-latching. When the overcurrent
fault is removed, the converter will immediately recover.
(13) Do not exceed maximum power specifications when adjusting the output trim.
(14) At zero output current, the output may contain low frequency components which exceed
the ripple specification. The output may be operated indefinitely with no load.
(15) Input Fusing: If reverse polarity is accidentally applied to the input, a body diode will
become forward biased and will conduct considerable current. To ensure reverse input
protection with full output load, always connect an external input fast-blow fuse in series
with the +V
IN
input. Use approximately twice the full input current rating with nominal
input voltage.
(16) “Hiccup” overcurrent operation repeatedly attempts to restart the converter with a brief,
full-current output. If the overcurrent condition still exists, the restart current will be
removed and then tried again. This short current pulse prevents overheating and damag-
ing the converter. Once the fault is removed, the converter immediately recovers normal
operation.
(17) Output accuracy is dependent on user-supplied trim resistors. To achieve high accuracy,
use ±1% or better tolerance metal-film resistors.
(18) At full power, on-board component package temperatures must not exceed +128°C.
(19) V
IN
must be 2 Volts or higher than V
OUT
for +3.3 to +5V outputs.
Trim Connections
+V
OUT
R
TRIM
Trim
R
LOAD
Ground
R
TRIM
(kΩ) =
1.182
V
OUT
− 0.591
Soldering Guidelines
Murata Power Solutions recommends the specifications below when installing these converters. These specifications vary depending on the solder type. Exceeding these specifica-
tions may cause damage to the product. Be cautious when there is high atmospheric humidity. We strongly recommend a mild pre-bake (100° C. for 30 minutes). Your production
environment may differ; therefore please thoroughly review these guidelines with your process engineers.
Wave Solder Operations for through-hole mounted products (THMT)
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