MURATA UEI25-050-D48

UEI25 Series
www.murata-ps.com
Single Output Isolated 25-Watt DC/DC Converters
Output (V)
Typical unit
Current (A)
3.3
7.5
48
5
5
48
12
2.1
48
FEATURES
PRODUCT OVERVIEW
„
Cost effective small footprint DC/DC converter,
ideal for high current applications
Featuring a full 25 Watt output in one square inch
of board area, the UEI25 series isolated DC/DC
converter family offers efficient regulated DC power
for printed circuit board mounting. The 0.96" x 1.1"
x 0.32" (24.4 x 27.9 x 8.1 mm) converter accepts a
2:1 input voltage range of 36 to 75 Volts DC, ideal
for telecom equipment. The industry-standard pinout fits larger 1" x 2" converters. The fixed output
voltage is tightly regulated. Applications include
small instruments, area-limited microcontrollers,
data communications equipment, remote sensor
systems, telephone equipment, vehicle and portable
electronics.
The UEI25 series includes full magnetic and
optical isolation with Basic protection up to 2250
Volts DC. For powering digital systems, the outputs
„
Industry standard 0.96" x 1.1" x 0.32" open
frame package and pinout
„
Input voltage range of 36-75 Vdc
„
3.3V, 5V, or 12Vdc fixed output voltages
„
Isolation up to 2250 VDC (basic)
„
Up to 25 Watts total output power with extensive self-protection shutdown features
„
High efficiency synchronous rectifier forward
topology up to 91%
„
Stable operation with no required external
components
Nominal Input (V)
offer fast settling to step transients and will accept
higher capacitive loads. Excellent ripple and noise
specifications assure compatibility to noise-susceptible circuits. For systems requiring controlled
startup/shutdown, an external remote On/Off control
may use a switch, transistor or digital logic.
A wealth of self-protection features avoid both
converter and external circuit faults. These include
input undervoltage lockout and overtemperature
shutdown. The outputs current limit using the
“hiccup” autorestart technique and the outputs are
short-circuit protected. Additional features include
output overvoltage and reverse conduction elimination. The high efficiency offers minimal heat buildup
and “no fan” operation.
„
Usable -40 to 85°C temperature range (with
derating)
„
Certified to UL 60950-1, CAN/CSA-C22.2 No.
60950-1, IEC60950-1, EN60950-1 safety
approvals, 2nd edition
F1
*TPMBUJPO
Barrier
+Vin (1)
+Vout (3)
t4XJUDIJOH
External
DC
Power
Source
On/Off
Control
(6)
Open = On
$MPTFE0GG
1PTJUJWF
polarity)
t'JMUFST
Controller
and Power
5SBOTGFS
t$VSSFOU4FOTF
Reference and
Error Amplifier
Trim (4)
-Vin (2)
-Vout (5)
Figure 1. Connection Diagram
Typical topology is shown. Murata Power Solutions
recommends an external fuse.
For full details go to
www.murata-ps.com/rohs
www.murata-ps.com
MDC_UEI25W.B03 Page 1 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
PERFORMANCE SPECIFICATIONS SUMMARY AND ORDERING GUIDE ➀ ➂
Output
Input
R/N (mVp-p)
Root Models ➀
VOUT
(V)
IOUT Total
(A, Power
max) (W) Typ. ➁ Max.
Regulation (Max.)
IIN,
min.
VIN
Nom. Range load
(V)
(V) (mA)
IIN,
full
load
(A)
Efficiency
Line
Load
Case (inches)
Case (mm)
3.3
7.5
25
50
80
±0.1%
±0.2%
48
36-75
75
0.58
87.0% 89.5%
0.96x1.1x0.32
24.4x27.9x8.1
P85
UEI25-050-D48
5
5
25
50
80
±0.1%
±0.2%
48
36-75
30
0.57
89.0%
0.96x1.1x0.32
24.4x27.9x8.1
P85
UEI25-120-D48
12
2.1
25.2
95
120
±0.1%
±0.1%
48
36-75
20
0.6
86.0% 87.5%
0.96x1.1x0.32
24.4x27.9x8.1
P85
UEI25-033-D48 ➃
Notes:
➀ Please refer to the part number structure for additional options and complete ordering part numbers.
➁ Ripple and Noise is shown at 20 MHz bandwidth.
➂ All specifications are at nominal line voltage and full load, +25 °C. unless otherwise
noted. See detailed specifications for full conditions.
Min.
Typ.
Package, C75
91%
Pinout
Output capacitors are 1 μF ceramic in parallel with 10 μF electrolytic. The input cap
is 4.7 μF ceramic, low ESR.
I/O caps are necessary for our test equipment and may not be needed for your application.
➃ Minimum load is 10% for rated specifications.
PART NUMBER STRUCTURE
UEI25 - 033 - D48 P M Lx - C
Unipolar Output Isolated
25-Watt Series
Nominal Output Voltage
in Tenths of a Volt
Input Voltage Range
D48 = 36-75 Vdc
RoHS-6 Hazardous Substance Compliance
(Does not claim EU RoHS exemption 7b, lead in solder)
Pin Length Option (through-hole only)
Blank = Std. pin length 0.25˝ (6.3mm)
L1 = 0.110˝ (2.79mm)*
L2 = 0.145˝ (3.68mm)*
Surface Mount Option
Blank = Through-hole mount
M = Surface mount (MSL rating 2)
On/Off Control Polarity:
P = Positive
N = Negative
Note:
Some model number combinations
may not be available.
Contact Murata Power Solutions.
*Alternate pin lengths may
require quantity order.
www.murata-ps.com
MDC_UEI25W.B03 Page 2 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
FUNCTIONAL SPECIFICATIONS – MODEL UEI25-033-D48
ABSOLUTE MAXIMUM RATINGS
Input Voltage, Continuous
Input Voltage, Transient
Conditions ➀
Full power operation
Operating or non-operating, 100 mS max.
duration
Input to output tested 100 mS
None, install external fuse
Power on or off, referred to -Vin
Minimum
Typical/Nominal
Maximum
Units
0
80
Vdc
0
100
Vdc
Isolation Voltage
2250
Vdc
Input Reverse Polarity
None
Vdc
On/Off Remote Control
0
15
Vdc
Output Power
0
25.25
W
Output Current
Current-limited, no damage, short-circuit protected
0
7.5
A
Storage Temperature Range
Vin = Zero (no power)
-55
125
˚C
Absolute maximums are stress ratings. Exposure of devices to greater than any of these conditions may adversely affect long-term reliability. Proper operation under conditions other than those
listed in the Performance/Functional Specifications Table is not implied or recommended.
INPUT
Operating voltage range
Recommended External Fuse
Start-up threshold
Undervoltage shutdown
Overvoltage shutdown
Reverse Polarity Protection
Internal Filter Type
Input current
Full Load Conditions
Low Line
Inrush Transient
Output in Short Circuit
No Load
Standby Mode (Off, UV, OT)
Reflected (back) ripple current ➁
Pre-biased startup
Fast blow
Rising input voltage
Falling input voltage
36
48
34
32
35.2
34.0
None
None
LC
None, install external fuse
Vin = nominal
Vin = minimum
0.58
0.79
0.05
50
75
1
30
Monotonic
Iout = minimum, unit=ON
Measured at input with specified filter
External output voltage < Vset
75
1.5
36
35.2
Vdc
A
Vdc
Vdc
Vdc
Vdc
0.60
0.81
A
A
A2-Sec.
mA
mA
mA
mA, RMS
100
100
2
GENERAL and SAFETY
Efficiency
Isolation
Isolation Voltage
Insulation Safety Rating
Isolation Resistance
Isolation Capacitance
Safety
Calculated MTBF
Calculated MTBF
Vin=48V, full load
Vin=36V, full load
87
86.5
Input to output, continuous
2250
89.5
87.5
%
%
Vdc
basic
10
Mohm
pF
1000
Certified to UL-60950-1, CSA-C22.2 No.60950-1,
IEC/EN60950-1, 2nd edition
Per MIL-HDBK-217F, ground benign,
Tambient=+30˚C
Per Telcordia SR332, issue 1, class 3, ground
fixed, Tambient=+40°C
Yes
TBD
Hours x 106
2
Hours x 106
DYNAMIC CHARACTERISTICS
Fixed Switching Frequency
Startup Time
Startup Time
Dynamic Load Response
Dynamic load di/dt
Dynamic Load Peak Deviation
300
Power On to Vout regulated
Remote ON to Vout regulated
50-75-50% load step, settling time to within
±2% of Vout
same as above
330
360
50
50
KHz
mS
mS
180
250
μSec
±30
2
±100
A/μSec
mV
1.2
15
V
V
mA
15
1.2
V
V
mA
FEATURES and OPTIONS
Remote On/Off Control ➃
"N" suffix
Negative Logic, ON state
Negative Logic, OFF state
Control Current
"P" suffix
Positive Logic, ON state
Positive Logic, OFF state
Control Current
ON = Ground pin or external voltage
OFF = Pin open or external voltage
-0.7
10
1
ON = Pin open or external voltage
OFF = Ground pin or external voltage
10
-0.7
1
www.murata-ps.com
MDC_UEI25W.B03 Page 3 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
FUNCTIONAL SPECIFICATIONS (CONT.) – MODEL UEI25-033-D48
OUTPUT
Total Output Power
Voltage
Nominal Output Voltage
Setting Accuracy
Output Voltage Range
Overvoltage Protection
Current
Output Current Range
Minimum Load ➂
Current Limit Inception
Short Circuit
Short Circuit Current
Short Circuit Duration (remove short for
recovery)
Short circuit protection method
Regulation ➄
Line Regulation
Load Regulation
Ripple and Noise
Temperature Coefficient
Maximum Capacitive Loading (10% ceramic,
90% Oscon)
MECHANICAL (Through Hole Models)
Outline Dimensions (no baseplate)
(Please refer to outline drawing)
Weight
Conditions ➀ ➂
Minimum
Maximum
Units
0.0
25.0
25.25
W
No trim
At 50% load
User-adjustable
Via magnetic feedback
3.267
-1
-10
4.2
3.30
3.333
+1
+10
5.7
Vdc
% of Vset.
% of Vnom.
Vdc
0.7575
7.575
10% minimum load
10
7.575
11
A
% of Iout
A
0.3
A
±0.1
±0.2
80
% of Vout
% of Vout
mV pk-pk
% of Vnom./°C
2000
μF
98% of Vnom., after warmup
8.5
5
Hiccup technique, autorecovery
Output shorted to ground, no damage
Continuous
Current limiting
Vin=min. to max., Vout=nom., 50% load
Iout=min. to max., Vin=48V
5 Hz- 20 MHz BW
At all outputs
Cap. ESR=<0.02Ω, full resistive load
Conditions ➀
50
0.02
0
Minimum
C75 case
WxLxH
Typical/Nominal
Maximum
0.9x1.1x0.32
22.86x27.9x8.1
0.32
9.07
0.04
1.016
Copper alloy
50
5
Through Hole Pin Diameter
Through Hole Pin Material
TH Pin Plating Metal and Thickness
Typical/Nominal
See Derating
Nickel subplate
Gold overplate
Units
Inches
mm
Ounces
Grams
Inches
mm
μ-inches
μ-inches
ENVIRONMENTAL
Operating Ambient Temperature Range
Storage Temperature
Thermal Protection/Shutdown
Electromagnetic Interference
Conducted, EN55022/CISPR22
Radiated, EN55022/CISPR22
Relative humidity, non-condensing
Altitude
With derating, 200 LFM
No derating, 200 LFM
Vin = Zero (no power)
Measured in center
External filter is required
-40
-40
-55
110
115
85
70
125
120
°C
°C
°C
°C
90
10,000
3048
Class
Class
%RH
feet
meters
B
B
To +85°C
must derate -1%/1000 feet
RoHS rating
10
-500
-152
RoHS-6
Notes
➀ Unless otherwise noted, all specifications are at nominal input voltage, nominal output voltage and full load. General conditions are +25˚ Celsius ambient temperature,
near sea level altitude, natural convection airflow. All models are tested and specified
with external parallel 1 μF and 10 μF multi-layer ceramic output capacitors. The external input capacitor is 4.7 μF ceramic. All capacitors are low-ESR types wired close
to the converter. These capacitors are necessary for our test equipment and may not
be needed in the user's application.
➁ Input (back) ripple current is tested and specified over 5 Hz to 20 MHz bandwidth.
Input filtering is Cbus=220 μF, Cin=33 μF and Lbus=12 μH.
➂ All models are stable and regulate to specification under minimum (10%) load.
Operation under no load will not damage the converter but may increase regulation,
output ripple, and noise.
➃ The Remote On/Off Control is referred to -Vin.
➄ Regulation specifications describe the output voltage changes as the line voltage or
load current is varied from its nominal or midpoint value to either extreme.
www.murata-ps.com
MDC_UEI25W.B03 Page 4 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
FUNCTIONAL SPECIFICATIONS – MODEL UEI25-050-D48
ABSOLUTE MAXIMUM RATINGS
Input Voltage, Continuous
Input Voltage, Transient
Conditions ➀
Full power operation
Operating or non-operating, 100 mS max.
duration
Input to output tested 100 mS
None, install external fuse
Power on or off, referred to -Vin
Minimum
Typical/Nominal
Maximum
Units
0
80
Vdc
0
100
Vdc
Isolation Voltage
2250
Vdc
Input Reverse Polarity
None
Vdc
On/Off Remote Control
0
15
Vdc
Output Power
0
25.25
W
Output Current
Current-limited, no damage, short-circuit protected
0
5
A
Storage Temperature Range
Vin = Zero (no power)
-55
125
˚C
Absolute maximums are stress ratings. Exposure of devices to greater than any of these conditions may adversely affect long-term reliability. Proper operation under conditions other than those
listed in the Performance/Functional Specifications Table is not implied or recommended.
INPUT
Operating voltage range
Recommended External Fuse
Start-up threshold
Undervoltage shutdown
Overvoltage shutdown
Reverse Polarity Protection
Internal Filter Type
Input current
Full Load Conditions
Low Line
Inrush Transient
Output in Short Circuit
No Load
Standby Mode (Off, UV, OT)
Reflected (back) ripple current ➁
Pre-biased startup
Fast blow
Rising input voltage
Falling input voltage
36
48
34
32
35
33.5
None
None
LC
None, install external fuse
Vin = nominal
Vin = minimum
0.57
0.76
0.05
50
30
1
30
Monotonic
Iout = minimum, unit=ON
Measured at input with specified filter
External output voltage < Vset
75
1.5
36
34.5
Vdc
A
Vdc
Vdc
Vdc
Vdc
0.59
0.79
A
A
A2-Sec.
mA
mA
mA
mA, RMS
100
50
3
GENERAL and SAFETY
Efficiency
Isolation
Isolation Voltage
Insulation Safety Rating
Isolation Resistance
Isolation Capacitance
Safety
Calculated MTBF
Calculated MTBF
Vin=48V, full load
Vin=36V, full load
89
89
Input to output, continuous
2250
91
91
%
%
Vdc
basic
10
Mohm
pF
2000
Certified to UL-60950-1, CSA-C22.2 No.60950-1,
IEC/EN60950-1, 2nd edition
Per MIL-HDBK-217F, ground benign,
Tambient=+30˚C
Per Telcordia SR332, issue 1, class 3, ground
fixed, Tambient=+40°C
Yes
TBD
Hours x 106
2
Hours x 106
DYNAMIC CHARACTERISTICS
Fixed Switching Frequency
Startup Time
Startup Time
Dynamic Load Response
Dynamic load di/dt
Dynamic Load Peak Deviation
300
Power On to Vout regulated
Remote ON to Vout regulated
50-75-50% load step, settling time to within
±2% of Vout
330
360
50
50
KHz
mS
mS
2
A/μSec
mV
0.7
15
V
V
mA
15
0.8
V
V
mA
200
same as above
μSec
±150
FEATURES and OPTIONS
Remote On/Off Control ➃
"N" suffix
Negative Logic, ON state
Negative Logic, OFF state
Control Current
"P" suffix
Positive Logic, ON state
Positive Logic, OFF state
Control Current
ON = Ground pin or external voltage
OFF = Pin open or external voltage
-0.7
10
1
ON = Pin open or external voltage
OFF = Ground pin or external voltage
10
-0.7
1
www.murata-ps.com
MDC_UEI25W.B03 Page 5 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
FUNCTIONAL SPECIFICATIONS (CONT.) – MODEL UEI25-050-D48
OUTPUT
Total Output Power
Voltage
Nominal Output Voltage
Setting Accuracy
Output Voltage Range
Overvoltage Protection
Current
Output Current Range
Minimum Load ➂
Current Limit Inception
Short Circuit
Short Circuit Current
Short Circuit Duration (remove short for
recovery)
Short circuit protection method
Regulation ➄
Line Regulation
Load Regulation
Ripple and Noise
Temperature Coefficient
Maximum Capacitive Loading (10% ceramic,
90% Oscon)
MECHANICAL (Through Hole Models)
Outline Dimensions (no baseplate)
(Please refer to outline drawing)
Weight
Conditions ➀ ➂
Minimum
Maximum
Units
0.0
25.0
25.25
W
No trim
At 50% load
User-adjustable
Via magnetic feedback
4.95
-1
-10
6
5.00
5.05
+1
+10
7.5
Vdc
% of Vset.
% of Vnom.
Vdc
0
5.0
No minimum load
6.8
5.0
7.3
A
% of Iout
A
0.3
A
±0.1
±0.2
80
% of Vout
% of Vout
mV pk-pk
% of Vnom./°C
2000
μF
98% of Vnom., after warmup
5.3
6.5
Hiccup technique, autorecovery
Output shorted to ground, no damage
Continuous
Current limiting
Vin=min. to max., Vout=nom., 50% load
Iout=min. to max., Vin=48V
5 Hz- 20 MHz BW
At all outputs
Cap. ESR=<0.02Ω, full resistive load
Conditions ➀
50
0.02
0
Minimum
C75 case
WxLxH
Typical/Nominal
Maximum
0.96x1.1x0.32
24.4x27.9x8.1
0.32
9.07
0.04
1.016
Copper alloy
50
5
Through Hole Pin Diameter
Through Hole Pin Material
TH Pin Plating Metal and Thickness
Typical/Nominal
See Derating
Nickel subplate
Gold overplate
Units
Inches
mm
Ounces
Grams
Inches
mm
μ-inches
μ-inches
ENVIRONMENTAL
Operating Ambient Temperature Range
Operating Case Temperature Range
Storage Temperature
Thermal Protection/Shutdown
Electromagnetic Interference
Conducted, EN55022/CISPR22
Radiated, EN55022/CISPR22
Relative humidity, non-condensing
Altitude
With derating, 200 LFM
No derating, 200 LFM, full power
No derating
Vin = Zero (no power)
Measured in center
External filter is required
-40
-40
-40
-55
110
115
85
82
105
125
120
°C
°C
°C
°C
°C
90
10,000
3048
Class
Class
%RH
feet
meters
B
B
To +85°C
must derate -1%/1000 feet
RoHS rating
10
-500
-152
RoHS-6
Notes
➀ Unless otherwise noted, all specifications are at nominal input voltage, nominal output voltage and full load. General conditions are +25˚ Celsius ambient temperature,
near sea level altitude, natural convection airflow. All models are tested and specified
with external parallel 1 μF and 10 μF multi-layer ceramic output capacitors. The external input capacitor is 4.7 μF ceramic. All capacitors are low-ESR types wired close
to the converter. These capacitors are necessary for our test equipment and may not
be needed in the user's application.
➁ Input (back) ripple current is tested and specified over 5 Hz to 20 MHz bandwidth.
Input filtering is Cbus=220 μF, Cin=33 μF and Lbus=12 μH.
➂ All models are stable and regulate to specification under no load.
➃ The Remote On/Off Control is referred to -Vin.
➄ Regulation specifications describe the output voltage changes as the line voltage or
load current is varied from its nominal or midpoint value to either extreme.
www.murata-ps.com
MDC_UEI25W.B03 Page 6 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
FUNCTIONAL SPECIFICATIONS – MODEL UEI25-120-D48
ABSOLUTE MAXIMUM RATINGS
Input Voltage, Continuous
Input Voltage, Transient
Conditions ➀
Full power operation
Operating or non-operating, 100 mS max.
duration
Input to output tested 100 mS
None, install external fuse
Power on or off, referred to -Vin
Minimum
Typical/Nominal
Maximum
Units
0
80
Vdc
0
100
Vdc
Isolation Voltage
2250
Vdc
Input Reverse Polarity
None
Vdc
On/Off Remote Control
0
15
Vdc
Output Power
0
25
W
Output Current
Current-limited, no damage, short-circuit protected
0
2.1
A
Storage Temperature Range
Vin = Zero (no power)
-55
125
˚C
Absolute maximums are stress ratings. Exposure of devices to greater than any of these conditions may adversely affect long-term reliability. Proper operation under conditions other than those
listed in the Performance/Functional Specifications Table is not implied or recommended.
INPUT
Operating voltage range
Recommended External Fuse
Start-up threshold
Undervoltage shutdown
Overvoltage shutdown
Reverse Polarity Protection
Internal Filter Type
Input current
Full Load Conditions
Low Line
Inrush Transient
Output in Short Circuit
No Load
Standby Mode (Off, UV, OT)
Reflected (back) ripple current ➁
Pre-biased startup
Fast blow
Rising input voltage
Falling input voltage
36
48
34
32
35.2
34.0
None
None
capacitive
None, install external fuse
Vin = nominal
Vin = minimum
0.600
0.809
0.05
50
20
1
30
Monotonic
Iout = minimum, unit=ON
Measured at input with specified filter
External output voltage < Vset
75
1.5
36
35.2
Vdc
A
Vdc
Vdc
Vdc
Vdc
0.617
0.842
A
A
A2-Sec.
mA
mA
mA
mA, RMS
100
35
2
GENERAL and SAFETY
Efficiency
Isolation
Isolation Voltage
Insulation Safety Rating
Isolation Resistance
Isolation Capacitance
Safety
Calculated MTBF
Calculated MTBF
Vin=48V, full load
86.0
Input to output, continuous
2250
87.5
%
Vdc
basic
10
Mohm
pF
1700
Certified to UL-60950-1, CSA-C22.2 No.609501, IEC/EN60950-1
Per MIL-HDBK-217F, ground benign,
Tambient=+30˚C
Per Telcordia SR332, issue 1, class 3, ground
fixed, Tambient=+40°C
Yes
TBD
Hours x 106
2
Hours x 106
DYNAMIC CHARACTERISTICS
Fixed Switching Frequency
Startup Time
Startup Time
Dynamic Load Response
Dynamic load di/dt
Dynamic Load Peak Deviation
295
Power On to Vout regulated
Remote ON to Vout regulated
50-75-50% load step, settling time to within
±1% of Vout
same as above
325
10
10
355
50
50
KHz
mS
mS
100
200
μSec
±250
1
±350
A/μSec
mV
0.7
15
V
V
mA
15
0.8
V
V
mA
FEATURES and OPTIONS
Remote On/Off Control ➃
"N" suffix
Negative Logic, ON state
Negative Logic, OFF state
Control Current
"P" suffix
Positive Logic, ON state
Positive Logic, OFF state
Control Current
ON = Ground pin or external voltage
OFF = Pin open or external voltage
-0.7
10
1
ON = Pin open or external voltage
OFF = Ground pin or external voltage
10
-0.7
1
www.murata-ps.com
MDC_UEI25W.B03 Page 7 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
FUNCTIONAL SPECIFICATIONS (CONT.) – MODEL UEI25-120-D48
OUTPUT
Total Output Power
Voltage
Nominal Output Voltage
Setting Accuracy
Output Voltage Range
Overvoltage Protection
Current
Output Current Range
Minimum Load ➂
Current Limit Inception
Short Circuit
Short Circuit Current
Short Circuit Duration (remove short for
recovery)
Short circuit protection method
Regulation ➄
Line Regulation
Load Regulation
Ripple and Noise
Temperature Coefficient
Maximum Capacitive Loading (10% ceramic,
90% Oscon)
MECHANICAL (Through Hole Models)
Outline Dimensions (no baseplate)
(Please refer to outline drawing)
Weight
Conditions ➀ ➂
Minimum
Maximum
Units
0.0
25.2
25.45
W
No trim
At 50% load
User-adjustable
Via magnetic feedback
11.88
-1
-10
14
12.00
12.12
+1
+10
22
Vdc
% of Vset.
% of Vnom.
Vdc
0.0
2.1
No minimum load
3
2.1
A
3.4
A
0.1
A
±0.075
±0.05
120
% of Vout
% of Vout
mV pk-pk
% of Vnom./°C
97% of Vnom., after warmup
2.3
19
Hiccup technique, autorecovery within ±1.25%
of Vout
Output shorted to ground, no damage
Continuous
Current limiting
Vin=min. to max., Vout=nom., 50% load
Iout=min. to max., Vin=48V
5 Hz- 20 MHz BW
At all outputs
Cap. ESR=<0.02Ω, full resistive load
Conditions ➀
95
0.02
0
Minimum
C75 case
WxLxH
470
Typical/Nominal
Maximum
0.96x1.1x0.32
24.38x27.94x8.13
0.32
9.07
0.04
1.016
Copper alloy
50
5
Through Hole Pin Diameter
Through Hole Pin Material
TH Pin Plating Metal and Thickness
Typical/Nominal
See Derating
Nickel subplate
Gold overplate
μF
Units
Inches
mm
Ounces
Grams
Inches
mm
μ-inches
μ-inches
ENVIRONMENTAL
Operating Ambient Temperature Range
Storage Temperature
Thermal Protection/Shutdown
Electromagnetic Interference
Conducted, EN55022/CISPR22
Radiated, EN55022/CISPR22
Relative humidity, non-condensing
Altitude
With derating, 200 LFM
Vin = Zero (no power)
Measured at hotspot
External filter is required
-40
-55
130
135
85
125
150
°C
°C
°C
90
10,000
3048
Class
Class
%RH
feet
meters
B
B
To +85°C
must derate -1%/1000 feet
RoHS rating
10
-500
-152
RoHS-6
Notes
➀ Unless otherwise noted, all specifications are at nominal input voltage, nominal output voltage and full load. General conditions are +25˚ Celsius ambient temperature,
near sea level altitude, natural convection airflow. All models are tested and specified
with external parallel 1 μF and 10 μF multi-layer ceramic output capacitors. The external input capacitor is 4.7 μF ceramic. All capacitors are low-ESR types wired close
to the converter. These capacitors are necessary for our test equipment and may not
be needed in the user's application.
➁ Input (back) ripple current is tested and specified over 5 Hz to 20 MHz bandwidth.
Input filtering is Cbus=220 μF, Cin=33 μF and Lbus=12 μH.
➂ All models are stable and regulate to specification under no load.
➃ The Remote On/Off Control is referred to -Vin.
➄ Regulation specifications describe the output voltage changes as the line voltage or
load current is varied from its nominal or midpoint value to either extreme.
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MDC_UEI25W.B03 Page 8 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
MECHANICAL SPECIFICATIONS, OPEN FRAME THROUGH-HOLE MOUNT
Dimensions are in inches (mm shown for ref. only).
Third Angle Projection
Case 75
24.4
0.96
Tolerances (unless otherwise specified):
.XX ± 0.02 (0.5)
.XXX ± 0.010 (0.25)
Angles ± 1˚
PIN #1
Components are shown for reference only.
27.9
1.10
INPUT/OUTPUT CONNECTIONS
Pin
Function P85
TOP VIEW
SIDE VIEW
MOUNTING
PLANE
.040±.002 PIN DIAMETER
.071 .002 SHOULDER DIAMETER
6X AT PINS 1-6
Negative Vin
3
Positive Vout
4
Output Trim
5
Negative Vout
6
On/Off Control*
These converters are plug-compatible to
competitive units. In case of pinout numbering
inconsistency, follow the pin FUNCTION, not
the pin number when laying out your PC board.
BOTTOM VIEW
END VIEW
20.32
0.800
0.58
[14.7]
0.15 TYP
[3.8]
0.475
[12.07]
REF
RECOMMENDED
PRI-SEC BARRIER
0.41
[10.4]
#3
10.16
0.400
CL
5.08
0.200
Positive Vin
2
*The Remote On/Off can be provided
with either positive (P suffix) or negative (N suffix) polarity
8.1
0.32 MAX
2.54
0.100
1
CL
#1
#2
#6
#4
10.16
0.400
6.3
0.25
0.30
[7.62]
10.16
0.400
CL
#5
Standard pin length is shown. Please refer to
the Ordering Guide for alternate pin lengths.
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MDC_UEI25W.B03 Page 9 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
SHIPPING TRAYS AND BOXES, THROUGH-HOLE MOUNT
Anti-static foam
Label
Label
Each tray is 6 x 5 units
(30 units per tray)
SHIPPING TRAY DIMENSIONS
UEI modules are supplied in a 30-piece (6 x 5) shipping tray. The tray is an anti-static closed-cell polyethylene foam. Dimensions are shown below.
6.4
Typ
[9.92]
252.0
28.4
Typ
6.4
Typ
18.0
5x 38.1
25.4
Typ
[9.92]
252.0
190.5
Ref
R 6.4
Typ
A
252.0
Ref
A
9.5 deep
Ref
4x 44.5
22.9
252.0
Ref
177.8
Ref
19.1
Ref
9.5 [.38 in]
Pocket
Depth
19.1 [.75 in]
SECTION A-A
Notes:
1. Material: Dow 220 antistat ethafoam
(Density: 34-35 kg/m3)
2. Dimensions: 252 x 252 x 19.1 mm
6 x 5 array (30 per tray)
3. All dimensions in millimeters [inches]
4. Tolerances unless otherwise specified: +1/-0
www.murata-ps.com
MDC_UEI25W.B03 Page 10 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
MECHANICAL SPECIFICATIONS, SURFACE MOUNT (MSL RATING 2)
Dimensions are in inches (mm shown for ref. only).
Third Angle Projection
Case 75
TOP VIEW
PIN #1
Tolerances (unless otherwise specified):
.XX ± 0.02 (0.5)
.XXX ± 0.010 (0.25)
Angles ± 1˚
24.4
0.96
Components are shown for reference only.
INPUT/OUTPUT CONNECTIONS
Pin
Function P85
27.9
1.10
SIDE VIEW
Positive Vin
2
Negative Vin
3
Positive Vout
4
Output Trim
5
Negative Vout
6
On/Off Control*
*The Remote On/Off can be provided
with either positive (P suffix) or negative (N suffix) polarity
MOUNTING
PLANE
These converters are plug-compatible to
competitive units. In case of pinout numbering
inconsistency, follow the pin FUNCTION, not
the pin number when laying out your PC board.
0.093 [2.4] TYP
BOTTOM VIEW
END VIEW
20.32
0.800
0.58
[14.7]
0.15 TYP
[3.8]
2.54
0.100
0.34
[8.64]
MAX
RECOMMENDED
PRI-SEC BARRIER
0.41
[10.4]
#3
10.16
0.400
CL
5.08
0.200
1
CL
#1
#2
#6
#4
0.30
[7.62]
10.16
0.400
#5
10.16
0.400
0.093
[2.4]
0.13 [3.3]
REF
CL
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MDC_UEI25W.B03 Page 11 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
RECOMMENDED SMT PAD LAYOUT
[20.32]
0.800
6X
[2.60 ±0.25]
.102 ±.010
6
[2.54]
0.100
5
2
4
CL
1
[2.54]
0.100
INPUT/OUTPUT CONNECTIONS
Pin
Function P85
[10.16]
0.400
[25.4]
1.00
[10.16]
0.400
3
1
Positive Vin
2
Negative Vin
3
Positive Vout
4
Output Trim
5
Negative Vout
6
On/Off Control*
*The Remote On/Off can be provided
with either positive (P suffix) or negative (N suffix) polarity
CL
[29.0]
1.14
SURFACE MOUNT TAPE AND REEL INFORMATION (MSL RATING 2)
PACKAGING CONFORMS TO EIA-481
CONVERTERS SHIPPING IN QUANTITIES
OF 100 PER REEL
NOTE: The SMT package has an MSL 2 rating.
3.00
0.118
2.00
0.079
5.0mm Nozzle Pick &
Place Location
23.10
0.909
56.0
2.20
32.00
1.260
Pitch
13.0
Feed (unwind) direction
Cover Tape
R.256
Dimensions in inches [mm]
9.27
0.365
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MDC_UEI25W.B03 Page 12 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
UEI25-033-D48 PERFORMANCE DATA
Maximum Current Temperature Derating @sea level
(airflow is from input to output)
8
Output Current (A
( mps)
Efficiency (%)
Efficiency vs. Line Voltage and Load Current @ 25°C
92
87
82
77
72
67
62
57
52
47
42
37
32
27
22
17
12
7
Vin = 36V
Vin = 48V
Vin = 60V
Vin = 75V
65 to 400 LFM
Vin = 36V, 48V and 60V
7
65 LFM
100 LFM
200 to 400
0 LFM
Vin = 75V
6
5
30
0.2
0.7
1.2
1.7
2.2
2.7
3.2
3.7
4.2
4.7
5.2
5.7
6.2
6.7
7.2
35
40
45
50
55
60
65
A bient Temperature (°C)
Am
70
75
80
85
7.7
Load Current (Amps)
Thermal image with "hot spot" at full load current with 63°C ambient, air flowing at
minimal rate of 65 LFM. Air is flowing across the converter from +Vo to -Vo at 48V input.
Identifiable and recommended maximum value to be verified in application.
On/Off ENABLE DELAY (Vin=48, Vout=nom, Iout=7.5A, Cload=0uF, Ta=+25°C.,
ScopeBW=20Mhz) Trace 1= Enable. Trace 4=Vout
On/Off ENABLE DELAY (Vin=48, Vout=nom, Iout=.7575mA, Cload=0uF, Ta=+25°C.,
ScopeBW=20Mhz) Trace 1= Enable. Trace 4=Vout
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MDC_UEI25W.B03 Page 13 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
UEI25-033-D48 PERFORMANCE DATA, CONTINUED
On/Off ENABLE DELAY (Vin=48, Vout=nom, Iout=7.5A, Cload=2000uF, Ta=+25°C.,
ScopeBW=20Mhz) Trace 1= Enable. Trace 4=Vout
Step Load Transient Response (Vin=48V, Vout=nom., Iout=50-75-50% of full load, Cload=
1 uFb ceramic || 10uF tantalum, Ta=+25°C., ScopeBW=20Mhz)
Output Ripple and Noise (Vin=48V, Vout=nom., Iout=7.5A, Cload= 1 uFb ceramic || 10uF
tantalum, Ta=+25°C., ScopeBW=20Mhz)
Output Ripple and Noise (Vin=48V, Vout=nom., Iout=.7575mA, Cload= 1 uFb ceramic ||
10uF tantalum, Ta=+25°C., ScopeBW=20Mhz)
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MDC_UEI25W.B03 Page 14 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
UEI25-050-D48 PERFORMANCE DATA
Power Dissipation vs. Load Current @ 25°C
3.50
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
75
3.00
Vin = 36V
Loss (Watts)
(
2.50
Vin = 48V
Vin = 60V
Vin = 75V
2.00
1.50
Vin = 36V
Vin = 48V
1.00
Vin = 60V
Vin = 75V
0.50
1.0
1.0
1.4
1.8
2.2
2.6
3.0
3.4
3.8
4.2
4.6
1.4
1.8
2.2
2.6
3.0
3.4
3.8
4.2
4.6
5.0
Load Current (A
( mps)
5.0
Load Current (Amps)
Maximum Current Temperature Derating @sea level
(VIN = 36V, 48V, 60V, and 75V, airflow is from pin 1 to pin 3)
5.1
5.0
Output Current (A
( mps)
Efficiency (%)
Efficiency vs. Line Voltage and Load Current @ 25°C
65 to 400 LFM
4.9
4.8
4.7
4.6
4.5
30
35
40
45
50
55
60
65
70
75
80
85
A bient temperature (°C)
Am
Thermal image with "hot spot" at full load current with 80°C ambient, air flowing at
minimal rate of 65 LFM. Air is flowing across the converter from +Vo to -Vo at 48V input.
Identifiable and recommended maximum value to be verified in application.
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MDC_UEI25W.B03 Page 15 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
UEI25-050-D48 PERFORMANCE DATA, CONTINUED
On/Off Enable Delay (Vin=48V, Vout=nom., Iout=no load, Cload=0 μF, Ta=+25°C.,
ScopeBW=20MHz) Trace 1=Enable, Trace 4=Vout
On/Off Enable Delay (Vin=48V, Vout=nom., Iout=5A, Cload=0 μF, Ta=+25°C.,
ScopeBW=20MHz) Trace 1=Enable, Trace 4=Vout
On/Off Enable Delay (Vin=48V, Vout=nom., Iout=5A, Cload=2000 μF, Ta=+25°C.,
ScopeBW=20MHz) Trace 1=Enable, Trace 4=Vout
Step Load Transient Response (Vin=48V, Vout=nom., Iout=50-75-50% of full load, Cload=1
μF ceramic || 10μF tantalum, Ta=+25°C., ScopeBW=20MHz)
Output Ripple and Noise (Vin=48V, Vout=nom., Iout=no load, Cload=1 μF ceramic || 10μF
tantalum, Ta=+25°C., ScopeBW=20MHz)
Output Ripple and Noise (Vin=48V, Vout=nom., Iout=5A, Cload=1 μF ceramic || 10μF
tantalum, Ta=+25°C., ScopeBW=20MHz)
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MDC_UEI25W.B03 Page 16 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
UEI25-120-D48 PERFORMANCE DATA
Efficiency vs. Line Voltage and Load Current @ 25°C
Power Dissipation vs. Load Current @ 25°C
89
4.46
88
3.96
87
3.46
85
Loss (Watts)
(
Efficiency (%)
86
Vin = 36V
Vin = 48V
84
Vin = 60V
Vin = 75V
83
2.96
2.46
1.96
Vin = 36V
82
Vin = 48V
1.46
Vin = 60V
Vin = 75V
81
80
0.96
79
0.46
0.4
78
0.4
0.6
0.8
0.9
1.1
1.3
1.4
1.6
1.8
1.9
0.6
0.8
0.9
1.1
1.3
1.4
1.6
1.8
1.9
2.1
Load Current (A
( mps)
2.1
Load Current (Amps)
Maximum Current Temperature Derating @sea level
(VIN = 48V, airflow is from pin 1 to pin 3)
2.25
2.2
2.2
2.175
2.15
Output Current (A
( mps)
Output Current (A
( mps)
Maximum Current Temperature Derating @sea level
(VIN = 36V, airflow is from pin 1 to pin 3)
65 LFM
100 LFM
200 LFM
300 LFM
2.1
2.05
2.0
1.95
2.15
65 LFM
100 LFM
200 LFM
2.125
2.1
2.075
2.05
2.025
1.9
65
70
75
80
85
A bient temperature (°C)
Am
Maximum Current Temperature Derating @sea level
(VIN = 60V, airflow is from pin 1 to pin 3)
2
65
70
75
A bient temperature (°C)
Am
80
85
Thermal image with "hot spot" at full load current with 65°C ambient, air flowing at
minimal rate of 65 LFM. Air is flowing across the converter from +Vo to -Vo at 48V input.
Identifiable and recommended maximum value to be verified in application.
2.2
Output Current (A
( mps)
2.175
2.15
65 LFM
100 LFM
200 LFM
2.125
2.1
2.075
2.05
2.025
2
65
70
75
A bient temperature (°C)
Am
80
85
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MDC_UEI25W.B03 Page 17 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
UEI25-120-D48 PERFORMANCE DATA, CONTINUED
Maximum Current Temperature Derating @sea level
(VIN = 75V, airflow is from pin 1 to pin 3)
On/Off ENABLE DELAY (Vin=48, Vout=nom, Iout=0A, Cload=0uF, Ta=+25°C.,
ScopeBW=20Mhz) Trace 1= Enable. Trace 4=Vout
2.2
Output Current (A
( mps)
2.15
2.1
65 LFM
100 LFM
200 LFM
300 LFM
2.05
1.95
1.9
65
70
75
80
85
A bient temperature (°C)
Am
On/Off ENABLE DELAY (Vin=48, Vout=nom, Iout=2.1A, Cload=0uF, Ta=+25°C.,
ScopeBW=20Mhz) Trace 1= Enable. Trace 4=Vout
On/Off ENABLE DELAY (Vin=48, Vout=nom, Iout=2.1A, Cload=2000uF, Ta=+25°C.,
ScopeBW=20Mhz) Trace 1= Enable. Trace 4=Vout
Stepload Transient Response (Vin = 48V, Iout = 25-75-25% of Imax, Cout = 1&10μF,
Ta = +25°C, Scope BW = 20MHz)
Output Ripple and Noise (Vin=48V, Iout = 2.1A, Cout = 1&10μF, Ta = +25°C,
Scope BW = 20MHz)
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MDC_UEI25W.B03 Page 18 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
TECHNICAL NOTES
Input Fusing
Certain applications and/or safety agencies may require fuses at the inputs of
power conversion components. Fuses should also be used when there is the
possibility of sustained input voltage reversal which is not current-limited. For
greatest safety, we recommend a fast blow fuse installed in the ungrounded
input supply line.
The installer must observe all relevant safety standards and regulations. For
safety agency approvals, install the converter in compliance with the end-user
safety standard.
Input Reverse-Polarity Protection
If the input voltage polarity is reversed, an internal diode will become forward
biased and likely draw excessive current from the power source. If this source
is not current-limited or the circuit appropriately fused, it could cause permanent damage to the converter.
Input Under-Voltage Shutdown and Start-Up Threshold
Under normal start-up conditions, converters will not begin to regulate properly
until the rising input voltage exceeds and remains at the Start-Up Threshold
Voltage (see Specifications). Once operating, converters will not turn off until
the input voltage drops below the Under-Voltage Shutdown Limit. Subsequent
restart will not occur until the input voltage rises again above the Start-Up
Threshold. This built-in hysteresis prevents any unstable on/off operation at a
single input voltage.
Users should be aware however of input sources near the Under-Voltage
Shutdown whose voltage decays as input current is consumed (such as capacitor
inputs), the converter shuts off and then restarts as the external capacitor recharges. Such situations could oscillate. To prevent this, make sure the operating
input voltage is well above the UV Shutdown voltage AT ALL TIMES.
Start-Up Delay
Assuming that the output current is set at the rated maximum, the Vin to Vout StartUp Delay (see Specifications) is the time interval between the point when the rising
input voltage crosses the Start-Up Threshold and the fully loaded regulated output
voltage enters and remains within its specified regulation band. Actual measured
times will vary with input source impedance, external input capacitance, input voltage slew rate and final value of the input voltage as it appears at the converter.
These converters include a soft start circuit to moderate the duty cycle of the
PWM controller at power up, thereby limiting the input inrush current.
The On/Off Remote Control interval from inception to VOUT regulated assumes that the converter already has its input voltage stabilized above the
Start-Up Threshold before the On command. The interval is measured from the
On command until the output enters and remains within its specified regulation
band. The specification assumes that the output is fully loaded at maximum
rated current.
Input Source Impedance
These converters will operate to specifications without external components,
assuming that the source voltage has very low impedance and reasonable input voltage regulation. Since real-world voltage sources have finite impedance,
performance is improved by adding external filter components. Sometimes only
a small ceramic capacitor is sufficient. Since it is difficult to totally characterize
all applications, some experimentation may be needed. Note that external input
capacitors must accept high speed switching currents.
Because of the switching nature of DC/DC converters, the input of these
converters must be driven from a source with both low AC impedance and
adequate DC input regulation. Performance will degrade with increasing input
inductance. Excessive input inductance may inhibit operation. The DC input
regulation specifies that the input voltage, once operating, must never degrade
below the Shut-Down Threshold under all load conditions. Be sure to use
adequate trace sizes and mount components close to the converter.
I/O Filtering, Input Ripple Current and Output Noise
All models in this converter series are tested and specified for input reflected
ripple current and output noise using designated external input/output components, circuits and layout as shown in the figures below. External input capacitors (CIN in the figure) serve primarily as energy storage elements, minimizing
line voltage variations caused by transient IR drops in the input conductors.
Users should select input capacitors for bulk capacitance (at appropriate
frequencies), low ESR and high RMS ripple current ratings. In the figure below,
the CBUS and LBUS components simulate a typical DC voltage bus. Your specific
system configuration may require additional considerations. Please note that the
values of CIN, LBUS and CBUS may vary according to the specific converter model.
TO
OSCILLOSCOPE
VIN
+
–
+
–
CURRENT
PROBE
1
+INPUT
LBUS
CBUS
CIN
2
−INPUT
CIN = 33μF, ESR < 700mΩ @ 100kHz
CBUS = 220μF, ESR < 100mΩ @ 100kHz
LBUS = 12μH
Figure 2. Measuring Input Ripple Current
In critical applications, output ripple and noise (also referred to as periodic
and random deviations or PARD) may be reduced by adding filter elements
such as multiple external capacitors. Be sure to calculate component temperature rise from reflected AC current dissipated inside capacitor ESR. In figure 3,
the two copper strips simulate real-world printed circuit impedances between
the power supply and its load. In order to minimize circuit errors and standardize tests between units, scope measurements should be made using BNC
connectors or the probe ground should not exceed one half inch and soldered
directly to the fixture.
Floating Outputs
Since these are isolated DC/DC converters, their outputs are “floating” with
respect to their input. The essential feature of such isolation is ideal ZERO
CURRENT FLOW between input and output. Real-world converters however do
exhibit tiny leakage currents between input and output (see Specifications).
These leakages consist of both an AC stray capacitance coupling component
and a DC leakage resistance. When using the isolation feature, do not allow
the isolation voltage to exceed specifications. Otherwise the converter may
be damaged. Designers will normally use the negative output (-Output) as
www.murata-ps.com
MDC_UEI25W.B03 Page 19 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
CAUTION: If you exceed these Derating guidelines, the converter may have
an unplanned Over Temperature shut down. Also, these graphs are all collected
near Sea Level altitude. Be sure to reduce the derating for higher altitude.
COPPER STRIP
+OUTPUT
C1
C2
SCOPE
RLOAD
−OUTPUT
COPPER STRIP
C1 = 1μF CERAMIC
C2 = 10μF LOW ES
LOAD 2-3 INCHES (51-76mm) FROM MODULE
Figure 3. Measuring Output Ripple and Noise (PARD)
the ground return of the load circuit. You can however use the positive output
(+Output) as the ground return to effectively reverse the output polarity.
Minimum Output Loading Requirements
These converters employ a synchronous rectifier design topology. All models
regulate within specification and are stable from 0% load to full load conditions,
unless otherwise specified. Operation under no load will not damage the converter but might, however, slightly increase regulation, output ripple, and noise.
Thermal Shutdown
To protect against thermal over-stress, these converters include thermal shutdown circuitry. If environmental conditions cause the temperature of the DC/
DC’s to rise above the Operating Temperature Range up to the shutdown temperature, an on-board electronic temperature sensor will power down the unit.
When the temperature decreases below the turn-on threshold, the converter
will automatically restart. There is a small amount of hysteresis to prevent
rapid on/off cycling. CAUTION: If you operate too close to the thermal limits, the
converter may shut down suddenly without warning. Be sure to thoroughly test
your application to avoid unplanned thermal shutdown.
Temperature Derating Curves
The graphs in the performance data section illustrate typical operation under a
variety of conditions. The Derating curves show the maximum continuous ambient
air temperature and decreasing maximum output current which is acceptable under
increasing forced airflow measured in Linear Feet per Minute (“LFM”). Note that
these are AVERAGE measurements. The converter will accept brief increases in temperature and/or current or reduced airflow as long as the average is not exceeded.
Note that the temperatures are of the ambient airflow, not the converter itself which is obviously running at higher temperature than the outside air. Also
note that “natural convection” is defined as very low flow rates which are not
using fan-forced airflow. Depending on the application, “natural convection” is
usually about 30-65 LFM but is not equal to still air (0 LFM).
Murata Power Solutions makes Characterization measurements in a closed
cycle wind tunnel with calibrated airflow. We use both thermocouples and an
infrared camera system to observe thermal performance. As a practical matter,
it is quite difficult to insert an anemometer to precisely measure airflow in
most applications. Sometimes it is possible to estimate the effective airflow if
you thoroughly understand the enclosure geometry, entry/exit orifice areas and
the fan flowrate specifications.
Output Overvoltage Protection (OVP)
This converter monitors its output voltage for an over-voltage condition using
an on-board electronic comparator. The signal is optically coupled to the primary side PWM controller. If the output exceeds OVP limits, the sensing circuit
will power down the unit, and the output voltage will decrease. After a time-out
period, the PWM will automatically attempt to restart, causing the output voltage to ramp up to its rated value. It is not necessary to power down and reset
the converter for this automatic OVP-recovery restart.
If the fault condition persists and the output voltage climbs to excessive
levels, the OVP circuitry will initiate another shutdown cycle. This on/off cycling
is referred to as “hiccup” mode.
Output Fusing
The converter is extensively protected against current, voltage and temperature
extremes. However, your application circuit may need additional protection. In the
extremely unlikely event of output circuit failure, excessive voltage could be applied
to your circuit. Consider using an appropriate external protection.
Output Current Limiting
As soon as the output current increases to approximately its overcurrent limit,
the DC/DC converter will enter a current-limiting mode. The output voltage will
decrease proportionally with increases in output current, thereby maintaining a
somewhat constant power output. This is commonly referred to as power limiting.
Current limiting inception is defined as the point at which full power falls
below the rated tolerance. See the Performance/Functional Specifications.
Note particularly that the output current may briefly rise above its rated value.
This enhances reliability and continued operation of your application. If the
output current is too high, the converter will enter the short circuit condition.
Output Short Circuit Condition
When a converter is in current-limit mode, the output voltage will drop as
the output current demand increases. If the output voltage drops too low, the
magnetically coupled voltage used to develop PWM bias voltage will also drop,
thereby shutting down the PWM controller. Following a time-out period, the
PWM will restart, causing the output voltage to begin rising to its appropriate
value. If the short-circuit condition persists, another shutdown cycle will initiate. This on/off cycling is called “hiccup mode.” The hiccup cycling reduces the
average output current, thereby preventing excessive internal temperatures.
Trimming the Output Voltage
The Trim input to the converter allows the user to adjust the output voltage over
the rated trim range (please refer to the Specifications). In the trim equations
and circuit diagrams that follow, trim adjustments use a single fixed resistor
connected between the Trim input and either Vout pin. Trimming resistors should
have a low temperature coefficient (±100 ppm/°C or less) and be mounted close
to the converter. Keep leads short. If the trim function is not used, leave the trim
unconnected. With no trim, the converter will exhibit its specified output voltage
accuracy.
There are two CAUTIONs to observe for the Trim input:
www.murata-ps.com
MDC_UEI25W.B03 Page 20 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
CAUTION: To avoid unplanned power down cycles, do not exceed EITHER the
maximum output voltage OR the maximum output power when setting the trim.
If the output voltage is excessive, the OVP circuit may inadvertantly shut down
the converter. If the maximum power is exceeded, the converter may enter
current limiting. If the power is exceeded for an extended period, the converter
may overheat and encounter overtemperature shut down.
CAUTION: Be careful of external electrical noise. The Trim input is a senstive
input to the converter’s feedback control loop. Excessive electrical noise may
cause instability or oscillation. Keep external connections short to the Trim
input. Use shielding if needed.
Trim Equations
Trim Up
Trim Down
<Connect trim resistor
between Trim and –Vout>
<Connect trim resistor
between Trim and +Vout>
UEI25-033-D48
RTUP (Ω) =
12775
VO – 3.3
– 2050
RTDOWN (Ω) =
5110 x (Vo –2.5)
3.3 – VO
CAUTION: While it is possible to control the On/Off with external logic if you
carefully observe the voltage levels, the preferred circuit is either an open
drain/open collector transistor or a relay (which can thereupon be controlled by
logic). The On/Off prefers to be set at approx. +15V (open pin) for the ON state,
assuming positive logic.
CAUTION: Do not apply voltages to the On/Off pin when there is no input
power voltage. Otherwise the converter may be permanently damaged.
On/Off Enable Control Ground Bounce Protection
To improve reliability, if you use a small signal transistor or other external
circuit to select the Remote On/Off control, make sure to return the LO side
directly to the –Vin power input on the DC/DC converter. To avoid ground
bounce errors, do not connect the On/Off return to a distant ground plane or
current-carrying bus. If necessary, run a separate small return wire directly to
the –Vin terminal. There is very little current (typically 1-5 mA) on the On/Off
control however, large current changes on a return ground plane or ground bus
can accidentally trigger the converter on or off. If possible, mount the On/Off
transistor or other control circuit adjacent to the converter.
– 2050
−INPUT
+OUTPUT
UEI25-050-D48
RTUP (Ω) =
12775
VO – 5
– 2050
RTDOWN (Ω) =
5110 x (Vo –2.5)
5 – VO
– 2050
ON/OFF
CONTROL
LOAD
TRIM
RTRIM DOWN
UEI25-120-D48
RTUP (Ω) =
25000
VO – 12
– 5110
RTDOWN (Ω) =
10000 (Vo-2.5)
12 – VO
– 5110
Where Vo = Desired output voltage. Adjustment accuracy is subject to resistor tolerances and factory-adjusted output accuracy. Mount trim resistor close
to converter. Use short leads.
Remote On/Off Control
On the input side, a remote On/Off Control can be specified with either positive
or negative logic as follows:
Positive: Models equipped with Positive Logic are enabled when the On/
Off pin is left open or is pulled high to +15VDC with respect to –VIN. An internal
bias current causes the open pin to rise to +VIN. Positive-polarity devices are
disabled when the On/Off is grounded or brought to within a low voltage (see
Specifications) with respect to –VIN.
Negative: Models with negative polarity are on (enabled) when the On/Off is
grounded or brought to within a low voltage (see Specifications) with respect to
–VIN. The device is off (disabled) when the On/Off is left open or is pulled high
to +15VDC Max. with respect to –VIN.
Dynamic control of the On/Off function should be able to sink the specified
signal current when brought low and withstand specified voltage when brought
high. Be aware too that there is a finite time in milliseconds (see Specifications)
between the time of On/Off Control activation and stable, regulated output. This
time will vary slightly with output load type and current and input conditions.
+INPUT
−OUTPUT
Figure 4. Trim adjustments to decrease Output Voltage using a Fixed Resistor
−INPUT
ON/OFF
CONTROL
+INPUT
+OUTPUT
TRIM
LOAD
R TRIM UP
−OUTPUT
Figure 5. Trim adjustments to increase Output Voltage using a Fixed Resistor
+VCC
ON/OFF
CONTROL
-INPUT
There are two CAUTIONs for the On/Off Control:
Figure 6. Driving the On/Off Control Pin (suggested circuit)
www.murata-ps.com
MDC_UEI25W.B03 Page 21 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
Emissions Performance
Murata Power Solutions measures its products for radio frequency emissions
against the EN 55022 and CISPR 22 standards. Passive resistance loads are
employed and the output is set to the maximum voltage. If you set up your
own emissions testing, make sure the output load is rated at continuous power
while doing the tests.
The recommended external input and output capacitors (if required) are
included. Please refer to the fundamental switching frequency. All of this
information is listed in the Product Specifications. An external discrete filter is
installed and the circuit diagram is shown below.
80
70
60
50
40
30
20
10
0
0.15
1.0
10.0
30.0
MHz
Resistive Load
C4
V+
C1
AV
UUT
L2
Black
QP
90
Graph 2. Conducted emissions performance with filter, Negative Line, CISPR 22, Class B,
full load, for UEI25-050-D48NM-C
Test Card
DC Source
dBμV
100
C2
C3
Vout+
Vin+
Resistive Load
inside a metal
container
C6
L1
dBμV
100
QP
Average
90
80
V-
Vin-
Vout-
70
60
50
40
C5
30
Figure 7. Conducted Emissions Test Circuit
20
10
0
0.15
[1] Conducted Emissions Parts List
Reference
L1
L2
C1, C2
C3
C4, C5
C6
Part Number
Description
Vendor
PE-62913
NC
VZ Series
VZ Series
Unknown
VZ Series
1mH, 6A
4.7uH, 3.6A
Electrolytic Capacitor 22ufd, 100V
Qty 2 - Electrolytic Capacitor 22ufd, 100V
3.3nF, 1500V
Electrolytic Capacitor 22ufd, 100V
Pulse
Murata
Panasonic
Panasonic
Unknown
Panasonic
1.0
10.0
30.0
MHz
Graph 3. Conducted emissions performance without filter, Negative Line, CISPR 22, Class
B, full load, for UEI25-050-D48NM-C
dBμV
100
QP
AV
90
80
70
[2] Conducted Emissions Test Equipment Used
„
Rohde & Schwarz EMI Test Receiver (9KHz – 1000MHz) ESPC
60
50
40
„
Rohde & Schwarz Software ESPC-1 Ver. 2.20
30
„
OHMITE 25W – 1 Ohm resistor combinations
20
10
„
DC Source Programmable DC Power Supply Model 62012P-100-50
0
0.15
[3] Conducted Emissions Test Results
dBμV
100
QP
1.0
10.0
30.0
MHz
Graph 4. Conducted emissions performance with filter, Negative Line, CISPR 22, Class B,
full load, for UEI25-120-D48P-C
AV
90
80
70
60
50
40
30
20
10
0
0.15
1.0
10.0
30.0
MHz
Graph 1. Conducted emissions performance with filter, Negative Line, CISPR 22, Class B,
full load, for UEI25-033-D48PM-C
[4] Layout Recommendations
Most applications can use the filtering which is already installed inside the
converter or with the addition of the recommended external capacitors. For
greater emissions suppression, consider additional filter components and/or
shielding. Emissions performance will depend on the user’s PC board layout,
the chassis shielding environment and choice of external components. Please
refer to Application Note for further discussion.
Since many factors affect both the amplitude and spectra of emissions, we
recommend using an engineer who is experienced at emissions suppression.
www.murata-ps.com
MDC_UEI25W.B03 Page 22 of 23
UEI25 Series
Single Output Isolated 25-Watt DC/DC Converters
Vertical Wind Tunnel
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œ«ÌˆV>Ê܈˜`œÜ
1˜ˆÌÊ՘`iÀ
ÌiÃÌÊ­11/®
Murata Power Solutions employs a custom-designed enclosed
vertical wind tunnel, infrared video camera system and test
instrumentation for accurate airflow and heat dissipation
analysis of power products. The system includes a precision low
flow-rate anemometer, variable speed fan, power supply input
and load controls, temperature gauges and adjustable heating
element.
6>Àˆ>Li
ëii`Êv>˜
The IR camera can watch thermal characteristics of the Unit
Under Test (UUT) with both dynamic loads and static steadystate conditions. A special optical port is used which is transparent to infrared wavelengths. The computer files from the IR
camera can be studied for later analysis.
,Ê6ˆ`iœÊ
>“iÀ>
i>̈˜}Ê
ii“i˜Ì
*ÀiVˆÃˆœ˜
œÜ‡À>Ìi
>˜i“œ“iÌiÀ
λÊLiœÜÊ11/
“Lˆi˜ÌÊ
Ìi“«iÀ>ÌÕÀi
Ãi˜ÃœÀ
ˆÀvœÜ
Vœˆ“>̜À
Figure 7. Vertical Wind Tunnel
Murata Power Solutions, Inc.
11 Cabot Boulevard, Mansfield, MA 02048-1151 U.S.A.
ISO 9001 and 14001 REGISTERED
Both through-hole and surface mount converters are soldered
down to a host carrier board for realistic heat absorption and
spreading. Both longitudinal and transverse airflow studies are
possible by rotation of this carrier board since there are often
significant differences in the heat dissipation in the two airflow
directions. The combination of both adjustable airflow, adjustable
ambient heat and adjustable Input/Output currents and voltages
mean that a very wide range of measurement conditions can be
studied.
The airflow collimator mixes the heat from the heating element to make uniform temperature distribution. The collimator
also reduces the amount of turbulence adjacent to the UUT by
restoring laminar airflow. Such turbulence can change the effective heat transfer characteristics and give false readings. Excess
turbulence removes more heat from some surfaces and less heat
from others, possibly causing uneven overheating.
Both sides of the UUT are studied since there are different thermal gradients on each side. The adjustable heating element and fan, built-in temperature gauges and no-contact IR camera mean that power supplies are tested in
real-world conditions.
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
notice.
© 2011 Murata Power Solutions, Inc.
www.murata-ps.com/support
MDC_UEI25W.B03 Page 23 of 23