Input Voltage:
"D5" Models 12 Volts
"D12" Models 20 Volts
"D48" Models 80 Volts
Input Reverse-Polarity Protection Current must be <2A. Brief duration
only. Fusing recommended.
Output Overvoltage Protection None
Output Current Maximum current and short-circuit
duration are model dependent. "D12"
and "D48" models can withstand
sustained output short circuits.
Storage Temperature –55 to +100°C
Lead Temperature (soldering, 10 sec.) +280°C
Floating Outputs
Since these are isolated DC/DC converters, their outputs are "fl oating."
Users may ground either the Common (pins 5 and 7) for normal usage or
the positive side (+Output, pins 6 and 8) to effectively reverse the output
polarity.
Filtering and Noise Reduction
All UST 3 Watt DC/DC Converters achieve their rated ripple and noise
specifi cations without the use of external input/output capacitors. In criti-
cal applications, input/output ripple and noise may be further reduced by
installing electrolytic capacitors across the input terminals and/or low-ESR
tantalum or electrolytic capacitors across the output terminals. The caps
should be located as close to the power converters as possible. Typical
values are listed in the tables below. In many applications, using values
greater than those listed will yield better results.
To Reduce Input Ripple
"D5" Models 47µF, 15V
"D12" Models 10µF, 35V
"D48" Models 4.7µF, 100V
To Reduce Output Ripple
5V Outputs 47µF, 10V, Low ESR
12/15V Outputs 22µF, 20V, Low ESR
In critical, space-sensitive applications, Murata Power Solutions may be able
to tailor the internal input/output fi ltering of these units to meet your specifi c
requirements. Contact our Applications Engineering Group for additional
details.
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 Specifi cations Table is not implied.
Absolute Maximum Ratings
TECHNICAL NOTES
Performance/Functional Specifi cations
Typical @ TA = +25°C under nominal line voltage and full-load conditions, unless noted. ➀
Input
Input Voltage Range:
"D5" Models 4.5-9 Volts (5V nominal)
"D12" Models 9-18 Volts (12V nominal)
"D48" Models 18-72 Volts (48V nominal)
Input Current See Ordering Guide
Input Filter Type ➁ Pi
Reverse-Polarity Protection Yes (Instantaneous, 2A maximum)
Output
VOUT Accuracy (50% load) ±1%, maximum
Temperature Coeffi cient ±0.02% per °C
Ripple/Noise (20MHz BW) ➁ See Ordering Guide
Line/Load Regulation See Ordering Guide
Effi ciency See Ordering Guide
Isolation Voltage ➂ 1000Vdc, minimum
Short Circuit Protection: ➃
"D5" Models Power-limiting technique, auto-recovery
"D12" and "D48" Models Hiccup technique, auto-recovery
Dynamic Characteristics
Transient Response (50% load step) 200µsec to ±1.5% of fi nal value
Switching Frequency:
"D48" Models 200kHz
"D5" and "D12" Models 170kHz
Environmental
Operating Temperature
(Ambient, no derating) –40 to +75°C
Storage Temperature –40 to +100°C
Physical
Dimensions 1.25" x 0.8" x 0.45" (31.8 x 20.3 x 11.4mm)
Case Material Diallyl phthalate, UL94V-0-rated
Pin Material Gold-plated copper alloy w/nickel underplate
Weight 0.5 ounces (14.2 grams)
➀ These power converters require a minimum 10% loading to maintain specifi ed regulation.
Operation under no-load conditions will not damage these devices; however, they may not
meet all listed specifi cations.
➁ Application-specifi c internal input/output fi ltering can be recommended for quantity orders
and perhaps added internally upon request. Contact Murata Power Solutions Applications
Engineering for details.
➂ Devices can be screened for quantity orders or modifi ed for higher guaranteed isolation
voltages. Contact Murata Power Solutions Applications Engineering for details.
➃ The current limit inception point is dependent on the input voltage. Therefore, it is possible
to draw current beyond the rated capacity. Users should fully characterize their load condi-
tions.
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UST Models
3W, Single Output DC/DC Converters
MDC_UST_3W.E01 Page 3 of 4
