NDL Series

Isolated 2W Wide Input Single Output DC/DC Converters

KDC_NDL.F05 Page 2 of 4

www.murata-ps.com/support

OUTPUT CHARACTERISTICS

Parameter

Typ.

Max.

Units

Voltage set point accuracy

All NDL05/12 input types with external input/output capacitors

±1

±3

%

All NDL24/48 input types with external input/output capacitors

±2

±5

Line regulation

All NDL05/12 input types, low line to high line with external input/output capacitors

0.05

0.5

%

All NDL24/48 input types, low line to high line with external input/output capacitors

0.04

0.4

Load regulation

All NDL05/12 input types, minimum load to rated load with external input/output capacitors

0.2

0.75

%

All NDL24/48 input types, minimum load to rated load with external input/output capacitors

0.2

0.75

Ripple

B/W = 20MHz to 300kHz with external input/output capacitors

5

10

mV rms

Noise

All NDL05 input types, B/W =DC to 20MHz with external input/output capacitors

50

100

mV p-p

All NDL12 input types, B/W =DC to 20MHz with external input/output capacitors

110

170

All NDL24/48 input types, B/W =DC to 20MHz with external input/output capacitors

50

100

Shutdown power

2.8

mW

ISOLATION CHARACTERISTICS

Parameter

Conditions

Min.

Typ.

Max.

Units

Isolation test voltage

Flash tested for 1 second

1000

Resistance

1GΩ

GENERAL CHARACTERISTICS

Parameter

Conditions

Min.

Typ.

Max.

Units

Control pin (CTRL) input current

Please refer to control pin application note

6

10

15

mA

Switching frequency

100

600

kHz

TEMPERATURE CHARACTERISTICS

Parameter

Conditions

Min.

Typ.

Max.

Units

Operation

-40

85

ºC

Storage

-50

130

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 NDL 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 NDL 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 NDL series has an EI ferrite core, 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. Refer to recommended test circuit for external input/output capacitors.