Datasheet

NKA Series
Isolated Sub-Miniature 1W Dual Output DC/DC Converters
KDC_NKA.J02 Page 2 of 7
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OUTPUT CHARACTERISTICS
Parameter Conditions Min. Typ. Max. Units
Rated Power
1
TA=-40°C to 120°C
1W
Voltage Set Point Accuracy See tolerance envelope
Line regulation High V
IN to low VIN 1.0 1.2 %/%
Load Regulation
2
10% load to rated load, 0312 & 0315 8 14
%
10% load to rated load, 3.3V output types 10 15
10% load to rated load, 5V output types 10 12
10% load to rated load, 9V output types 6.5 8
10% load to rated load, 12V output types 6 8.5
10% load to rated load, 15V output types 6 7
Ripple and Noise
BW=DC to 20MHz, 0312 & 0315 25 60
mV p-p
BW=DC to 20MHz, 3.3V output types 40 80
BW=DC to 20MHz, 5V output types 50 75
BW=DC to 20MHz, 9V output types 40 65
BW=DC to 20MHz, 12V output types 40 60
BW=DC to 20MHz, 15V output types 40 60
ISOLATION CHARACTERISTICS
Parameter Conditions Min. Typ. Max. Units
Isolation test voltage Flash tested for 1 second 3000 VDC
Resistance Viso= 1000VDC 10 GΩ
GENERAL CHARACTERISTICS
Parameter Conditions Min. Typ. Max. Units
Switching frequency
0303, 0305, 0312, 0315, 0503 and 0505XE 95
kHz
All other types 120
TEMPERATURE CHARACTERISTICS
Parameter Conditions Min. Typ. Max. Units
Specification All output types -40 85
°C
Storage -50 130
Case temperature rise above
ambient
5V output types 30
All other output types 21
Cooling Free air convection
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 NKA 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 NKA 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 materials,
construction and environment. The NKA series has toroidal isolation transformers, with no additional insulation between primary and secondary windings of enameled wire. While
parts can be expected to withstand several times the stated test voltage, the isolation capability does depend on the wire insulation. Any material, including this enamel (typically
polyurethane) is susceptible to eventual chemical degradation when subject to very high applied voltages thus implying that the number of tests should be strictly limited. We
therefore strongly advise against repeated high voltage isolation testing, but if it is absolutely required, that the voltage be reduced by 20% from specified test voltage.
This consideration equally applies to agency recognized parts rated for better than functional isolation where the wire enamel insulation is always supplemented by a further
insulation system of physical spacing or barriers.
1. See Derating Graphs.
2. 12V input types have typically 3% less load regulation.