additional external load capacitance the rise time of the input voltage will determine the maximum external
capacitance value for guaranteed start up. The slower the rise time of the input voltage the greater the maximum value of the
additional external capacitance for reliable start up.
INPUT CHARACTERISTICS
Parameter
Voltage range
Conditions
Continuous operation, 24V input types
Continuous operation, 48V input types
Min.
21.6
43.2
Typ.
24
48
Max.
26.4
52.8
Units
V
OUTPUT CHARACTERISTICS
Parameter
Rated Power
Voltage Set Point Accuracy
Line regulation
Load Regulation
Ripple and Noise
2
DESCRIPTION
The NMA series of DC/DC converters are the
standard buliding blocks for on-board distrib-
uted power systems. They are ideally suited for
providing dual rail supplies on primarily digital
boards with the added benefit of galvanic isolation
to reduce switching noise. All of the rated power
may be drawn from a single pin provided the total
load does not exceed 1 watt.
Conditions
T
A
=0
°C
to 70
°C
See tolerance envelope
High V
IN
to low V
IN
10% load to rated load, 5V output types
10% load to rated load, all other output types
BW=DC to 20MHz, all input types
Min.
Typ.
Max.
1
1.2
15
10
150
Units
W
%/%
%
mV p-p
ABSOLUTE MAXIMUM RATINGS
Lead temperature 1.5mm from case for 10 seconds
Internal power dissipation
Input voltage V
IN
, NMA24 types
Input voltage V
IN,
NMA48 types
1. Calculated using MIL-HDBK-217F with nominal input voltage at full load.
2. See derating graph.
All specifications typical at T
A
=25°C, nominal input voltage and rated output current unless otherwise specified.
300°C
450mW
28V
54V
For full details go to
www.murata-ps.com/rohs
www.murata-ps.com/support
KDC_NMAC2.G02
Page 1 of 4
NMA 24V & 48V Series
Isolated 1W Dual Output DC/DC Converters
ISOLATION CHARACTERISTICS
Parameter
Isolation test voltage
Resistance
Conditions
Flash tested for 1 second
Viso= 500VDC
Min.
1000
10
Typ.
Max.
Units
VDC
GΩ
GENERAL CHARACTERISTICS
Parameter
Switching frequency
Conditions
All input types
Min.
Typ.
100
Max.
Units
kHz
TEMPERATURE CHARACTERISTICS
Parameter
Specification
Storage
Cooling
Conditions
All output types
Free air convection
Min.
0
-55
Typ.
Max.
70
150
Units
°C
RoHS COMPLIANCE INFORMATION
This series is compatible with RoHS soldering systems with a peak wave solder temperature of 300°C for 10 seconds. The pin termination
finish on the SIP package type is Tin Plate, Hot Dipped over Matte Tin with Nickel Preplate. The DIP types are Matte Tin over Nickel Preplate.
Both types in this series are backward compatible with Sn/Pb soldering systems.
For further information, please visit www.murata-ps.com/rohs
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 NMA 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 NMA 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 NMA 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.
APPLICATION NOTES
Minimum load
The minimum load to meet datasheet specification is 10% of the full rated load across the specified input voltage range. Lower than 10% minimum loading will result in
an increase in output voltage, which may rise to typically double the specified output voltage if the output load falls to less than 5%.
www.murata-ps.com/support
KDC_NMAC2.G02
Page 2 of 4
NMA 24V & 48V Series
Isolated 1W Dual Output DC/DC Converters
PACKAGE SPECIFICATIONS
MECHANICAL DIMENSIONS
PIN CONNECTIONS - 14 PIN DIP
DIP package
0.77 (19.50)
SIP package
0.77
(19.50)
Pin
1
7
8
9
11
14
Function
-V
IN
NC
OV
+V
OUT
-V
OUT
+V
IN
0.385
(9.80)
NMA2405DC
XYYWWi
0.236
(6.00)**
0.268
(6.80)*
0.394
(10.00)
1
NMA2405SC
XYYWWi
0.022 (0.55)
0.0178 (0.45)
PIN CONNECTIONS - 7 PIN SIP
2
4 5 6
0.1 (2.54)
0.22 (0.55)
0.0178 (0.45)
0.0118 (0.30)
0.0079 (0.20)
0.05
(1.25)
0.5 (12.70)
0.181 (4.60)
0.142 (3.60)
0.022 (0.55)
0.0178 (0.45)
0.181 (4.60)
0.141 (3.60)
Pin
1
2
4
5
6
Function
+V
IN
-V
IN
-V
OUT
OV
+V
OUT
0.1 (2.54)
0.043
(1.09)
0.079
(2.00)
1
0.3 (7.62)
14
0.084
(2.13)
11
0.6 (15.24)
7
9 8
0.0118 (0.30)
0.0079 (0.20)
* 0.303 (7.70) for 48V variants
** 0.295 (7.50) for 48V variants
All dimensions in inches ±0.01 (mm ±0.25mm). All pins on a 0.1 (2.54) pitch and within ±0.01 (0.25) of true position.
Weight:
2.4g (24V DIP)
2.9g (48V DIP)
2.2g (24V SIP)
2.9g (48V SIP)
TEMPERATURE DERATING GRAPH
1.5
TOLERANCE ENVELOPE
+10%
Output Power (W)
Output Voltage
1.0
70°C
+5%
V
NOM
Typical
Load Lin
e
+2.5%
-2.5%
-7.5%
0.5 Safe Operating Area
125ºC
0
0
50
100
Ambient Temperature (ºC)
150
10
75
50
25
Output Load Current (%)
100
The voltage tolerance envelope shows typical load regulation characteristics
for this product series. The tolerance envelope is the maximum output volt-
age variation due to changes in output loading.
www.murata-ps.com/support
KDC_NMAC2.G02
Page 3 of 4
NMA 24V & 48V Series
Isolated 1W Dual Output DC/DC Converters
PACKAGE SPECIFICATIONS (continued)
RECOMMENDED FOOTPRINT DETAILS
14 Pin DIP Package
0.045 (1.15)
Ø 0.039 (1.00)
5 HOLES
0.00394 (0.1)
7 Pin SIP Package
0.045 (1.15)
Ø 0.039 (1.00)
5 HOLES
0.00394 (0.1
0.1 (2.54)
0.1 (2.54)
0.1 (2.54)
0.1 (2.54)
TUBE OUTLINE DIMENSIONS
14 Pin DIP Tube
7 Pin SIP Tube
Unless otherwise stated all dimensions in inches (mm) ±0.5mm.
Tube length (14 Pin DIP) : 20.47 (520mm ±2mm).
Tube length (7 Pin SIP) : 20.47 (520mm ±2mm).
Tube Quantity : 25
Murata Power Solutions, Inc.
11 Cabot Boulevard, Mansfield, MA 02048-1151 U.S.A.
ISO 9001 and 14001 REGISTERED
This product is subject to the following
operating requirements
and the
Life and Safety Critical Application Sales Policy:
Refer to:
http://www.murata-ps.com/requirements/
Murata Power Solutions, Inc. makes no representation that the use of its products in the circuits described herein, or the use of other
technical information contained herein, will not infringe upon existing or future patent rights. The descriptions contained herein do not imply
the granting of licenses to make, use, or sell equipment constructed in accordance therewith. Specifications are subject to change without
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