NPH25S SERIES
Isolated 25W Single Output DC-DC Converters
SELECTION GUIDE
Nominal
Input Voltage
Output
Voltage
Output
Current
Efficiency
Order Code
1
NPH25S2403i
NPH25S2405i
NPH25S2412i
NPH25S2415i
NPH25S4803i
NPH25S4805i
NPH25S4812i
NPH25S4815i
(V)
24
24
24
24
48
48
48
48
(V)
3.4
5.1
12.1
15.1
3.4
5.1
12.1
15.1
(A)
7.3
5.0
2.1
1.7
7.3
5.0
2.1
1.7
(%)
81
84
86
87
83
85
88
89
FEATURES
■
High Efficiency to 89%
■
Power Density up to 1.78W/cm
(28W/in
3
)
■
1.5kV Input to Output Isolation
■
Industry Standard Pinout
■
UL 1950 Recognised
■
Non Latching Current Limit
■
Constant 350kHz Frequency
■
Versatile Control Options
■
Continuous Rating to 30W at 60°C
Without Heatsink
■
Operation to Zero Load
■
Protected Against All Load Faults
■
Internal Over Temperature Protection
■
Uses No Electrolytic Capacitors
■
UL 94V-0 Package Materials
DESCRIPTION
The NPH25S series of DC-DC Converters
combines ease of application with versatility.
The pin pattern is based on the popular
industry standard, but two additional pins
may optionally be fitted to provide a variety
of features not commonly found on units of
this type. High efficiency enables full rating to
be achieved in a small package without
heatsinking, and a high surge capability will
provide for start-up and transient loads, whilst
being thermally protected against sustained
overload. Overload protection of the
“constant current” type ensures start-up
into complex load conditions. The copper
case achieves efficient heat transfer and
screening. The product range has been
recognised by Underwriters Laboratory (UL)
to UL 1950 for operational insulation, file
number E179522 applies.
3
INPUT CHARACTERISTICS
Parameter
Conditions
MIN
NOM
MAX
Units
Voltage Range
Continuous operation, 24V input types
Continuous operation, 48V input types
18
36
24
48
36
75
V
OUTPUT CHARACTERISTICS
Parameter
Conditions
MIN
TYP
MAX
Units
Voltage Set
Point Error
Overall
Voltage Error
Temperature Coefficient
of Output Voltage
(slope)
Deviation of
Output Voltage
Line Regulation
Load Regulation
Ripple
50% load
Case temperature –40°C to 110°C
Load 0% - 100%
Input specified range
0.5
2.5
250
%
%
ppm°C
%
%
%
mV
Temperature MIN-MAX
Operating voltage range, 50% load
0% - 100% rated load
2
rms
0.5
1
0.1
0.5
70
CONTROL CHARACTERISTICS
Parameter
Conditions
MIN
TYP
MAX
Units
Voltage Trimming
Range
Remote Switch Input
3
(voltage relative
to input negative)
At rated load,
Trim control at either output
Not operating
Operating, open circuit voltage
Time from application of valid input
voltage to output being in specification
Specified drive signal
±10
-15
9
0
10
25
320
330
350
1.5
11
50
440
395
%
V
mS
kHz
kHz
Start Delay
Synchronisation
3
Switching Frequency
ABSOLUTE MAXIMUM RATINGS
Input voltage, 24V input types
Input voltage, 48V input types
Output Voltage
Output trim control
Synchronisation/shutdown control
–0.5V to 40V
4
–0.5V to 80V
4
–0.3V to regulated voltage
–1V to +30V
±15V relative to input return
ISOLATION CHARACTERISTICS
Parameter
Conditions
MIN
TYP
MAX
Units
Isolation Voltage
Resistance
Flash tested for 1 second
Viso=500VDC
1500
1
4000
VDC
GΩ
1 1 If optional pins ADJ and SS are required (as indicated in the pin connections diagram) prefix the ending “i” with
an E when ordering, e.g. NPH25S4803Ei.
2 A minimum load of 10% of rating is recommended for typical applications.
3 Optional where fitted.
4 Absolute maximum value for 30 seconds. Prolonged operation may damage the product.
All specifications typical at TA=25°C, nominal input voltage and rated output current unless otherwise specified.