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LME Series
Isolated 250mW Single Output DC/DC Converters
FEATURES RoHS compliant Single output rail 1kVDC isolation High efficiency for low power applications SIP & DIP package styles Power density 0.36W/cm3 UL 94V-0 package material Footprint from 0.69cm2 5V & 12V input 5V, 9V, 12V & 15V output No heatsink required Internal SMD construction Fully encapsulated with toroidal magnetics No external components required MTTF up to 2.7 million hours Custom solutions available Pin compatible with NKE, NME, NML &
MEE3 series PCB mounting
PRODUCT OVERVIEW
The LME series of DC/DC converters are optimised for low-power operation. They are ideally suited to generating a negative supply where only a positive rail exists.
SELECTION GUIDE
Nominal Input
Order Code
Voltage
V
LME0505DC
5
LME0509DC
5
LME0512DC
5
LME0515DC
5
LME0505SC
5
LME0509SC
5
LME0512SC
5
LME0515SC
5
LME1205DC
12
LME1209DC
12
LME1212DC
12
LME1215DC
12
LME1205SC
12
LME1209SC
12
LME1212SC
12
LME1215SC
12
Output Voltage
V 5 9 12 15 5 9 12 15 5 9 12 15 5 9 12 15
Output Current
mA 50 28 21 16 50 28 21 16 50 28 21 16 50 28 21 16
Efficiency
% 70 75 75 75 70 75 75 75 70 75 75 75 70 75 75 75
Isolation Capacitance
pF 29 37 41 40 29 37 41 40 38 40 43 45 38 40 43 45
MTTF1
kHrs 2279 1139 624 357 2279 1139 624 357 536 434 330 237 536 434 330 237
Package Style DIP
SIP
DIP
SIP
INPUT CHARACTERISTICS
Parameter
Conditions
Voltage range
Continuous operation, 5V input types Continuous operation, 12V input types
Min. Typ. Max. Units
4.5 5.0 5.5 10.8 12 13.2
V
OUTPUT CHARACTERISTICS
Parameter
Conditions
Rated Power2
TA=0°C to 70°C
Voltage Set Point Accuracy See tolerance envelope
Line regulation
High VIN to low VIN
Load Regulation2
10% load to rated load, 5V output types 10% load to rated load, all other types
Ripple and Noise
BW=DC to 20MHz, all output types
Min. Typ. Max. Units 0.25 W
1.0 1.2 %/% 15 % 10 100 mV p-p
ISOLATION CHARACTERISTICS
Parameter
Conditions
Isolation test voltage
Flash tested for 1 second
Resistance
Viso= 500VDC
Min. Typ. Max. Units 1000 VDC
1 GΩ
GENERAL CHARACTERISTICS
Parameter
Conditions
Switching frequency
All input types
Min. Typ. Max. Units 100 kHz
ABSOLUTE MAXIMUM RATINGS Lead temperature 1.5mm from case for 10 seconds Input voltage VIN, LME05 types Input voltage VIN, LME12 types
300°C 7V 15V
1. Calculated using MIL-HDBK-217F with nominal input voltage at full load. 2. See derating curve. All specifications typical at TA=25°C, nominal input voltage and rated output current unless otherwise specified.
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KDC_LMEC.E05 Page 1 of 4
LME Series
Isolated 250mW Single Output DC/DC Converters
TEMPERATURE CHARACTERISTICS
Parameter
Conditions
Specification
All output types
Storage
Cooling
Free air convection
Min. Typ. Max. Units 0 70 °C -50 130
Output Power (W) Output Voltage
TEMPERATURE DERATING GRAPH
0.375
0.250
70°C
0.125 0 0
Safe Operating Area
125°C
50 100 150 Ambient Temperature (°C)
TOLERANCE ENVELOPE +10% +5% V
NOM
Typical Load Line
+2.5% -2.5% -7.5%
10 25 50 75 100 Output Load Current (%)
The voltage tolerance envelope shows typical load regulation characteristics for this product series. The tolerance envelope is the maximum output voltage variation due to changes in output loading.
TECHNICAL NOTES
ISOLATION VOLTAGE
‘Hi Pot Test’, ‘Flash Tested’, ‘Withstand Voltage’, ‘Proof Voltage’, ‘Dielectric Withstand Voltage’ & ‘Isolation Test Voltage’ are all terms that relate to the same thing, a test voltage, applied for a specified time, across a component designed to provide electrical isolation, to verify the integrity of that isolation.
Murata Power Solutions LME series of DC/DC converters are all 100% production tested at their stated isolation voltage. This is 1kVDC for 1 second.
A question commonly asked is, “What is the continuous voltage that can be applied across the part in normal operation?”
For a part holding no specific agency approvals, such as the LME series, both input and output should normally be maintained within SELV limits i.e. less than 42.4V peak, or 60VDC. The isolation test voltage represents a measure of immunity to transient voltages and the part should never be used as an element of a safety isolation system. The part could be expected to function correctly with several hundred volts offset applied continuously across the isolation barrier; but then the circuitry on both sides of the barrier must be regarded as operating at an unsafe voltage and further isolation/insulation systems must form a barrier between these circuits and any user-accessible circuitry according to safety standard requirements.
REPEATED HIGH-VOLTAGE ISOLATION TESTING
It is well known that repeated high-voltage isolation testing of a barrier component can actually degrade isolation capability, to a lesser or greater degree depending on mate.