BEL 0RSB

ISOLATED DC/DC CONVERTERS
18 Vdc - 75 Vdc Input 5 Vdc / 8 A Output, 1/16 Brick
Bel Power Inc., a subsidiary of Bel Fuse Inc.
May 24, 2011
0RSB-40U05B
RoHS Compliant
PRELIMINARY
Rev.A
Features

Isolated

Input Under Voltage Lockout

Fixed Frequency

Output Over Voltage Shutdown

High Efficiency

OCP/SCP

High Power Density

Over Temperature Protection

Low Cost

Positive/Negative Remote Sense

Output Voltage Trim

Remote On/Off

Basic Insulation

Through Hole

Class 2, Category 2, Isolated DC/DC Converter (refer to IPC-9592)

UL60950-1 Recognized (UL/cUL) (Pending)
Applications

Networking

Computers and peripherals

Telecommunications
Description
The 0RSB-40U05B is an isolated dc/dc converter that operates from a nominal 24 Vdc or 48 Vdc source. The
unit will provide up to 40 W of output power from an 18-75 Vdc wide input range. The unit is designed to be
highly efficient and low cost. Features include remote on/off, over current protection and under voltage lockout.
This converter is provided in an industry standard sixteenth brick package.
Part Selection
Output Voltage
Input Voltage
5.0 Vdc
18 Vdc - 75 Vdc
Max. Output
Current
8A
Max. Output
Power
40 W
Typical Efficiency
87%
Model Number
Active Low
0RSB-40U05B
Note: Add “G” suffix at the end of the model number to indicate Tray Packaging.
Part Number Explanation
0 R SB – 40 U 05 B
1 2
3
4
5
6 7
1---Through hole
2---RoHS 6, change “R” to “7” means RoHS 5
3---Series name, 1/16 Brick
4---Series code
5---Input range (18-75V)
6---Output voltage (5V)
7---Enable, active low, pin length is 0.11 inch
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302  Tel 201-432-0463  Fax 201-432-9542  www.belfuse.com
1
ISOLATED DC/DC CONVERTERS
18 Vdc - 75 Vdc Input 5 Vdc / 8 A Output, 1/16 Brick
Bel Power Inc., a subsidiary of Bel Fuse Inc.
May 24, 2011
Absolute Maximum Ratings
Max
Unit
-
80
V
-
100
V
-0.3
-
18
V
-
-
1500
V
Ambient Temperature
-40
-
85
C
Storage Temperature
-55
-
125
C
Parameter
Input Voltage (continuous)
Input Transient Voltage
Remote On/Off
I/O Isolation Voltage
Min
Typ
-0.3
-
Notes
100mS maximum
Note: Ratings used beyond the maximum ratings may cause a reliability degradation of the converter or may
permanently damage the device.
Input Specifications
Parameter
Input Voltage
Min
18
Typ
48
Max
75
Unit
V
Input Current (full load)
-
-
3.5
A
Input Current (no load)
-
60
120
mA
Remote Off Input Current
-
1
3
mA
Input Reflected Ripple Current
(pk-pk)
-
20
50
mA
Input Reflected Ripple Current
(rms)
-
3
7
mA
78
-
82
V
I t Inrush Current Transient
-
0.01
0.02
As
Turn-on Voltage Threshold
16.6
17.2
17.8
V
Turn-off Voltage Threshold
16.2
16.8
17.4
V
Input Over Voltage Lockout
2
Notes
With simulated source impedance of
10uH, 5Hz to 20MHz. Use a
100uF/100V electrolytic capacitor with
ESR=1 ohm max, at 200KHz@25°C.
2
Note: All specifications are typical at nominal input, full load at 25 C unless otherwise stated.
Output Specifications
Parameter
Min
Typ
Max
Unit
4.925
5.000
5.075
V
Load Regulation
-
±4
±9
mV
Line Regulation
-
±4
±9
mV
Regulation Over Temperature(-40 C to +85 C)
-
±15
±30
mV
Total Regulation
-
±23
±48
mV
Ripple and Noise (pk-pk)
-
70
120
mV
Ripple and Noise (rms)
-
25
50
mV
Output Current Range
0
-
8
A
Output Voltage Set Point
Notes
Vin=48 V; Io=50% load
0-20MHz BW, with a 1µF
ceramic capacitor and a
10uF Tantalum cap at
output.
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302  Tel 201-432-0463  Fax 201-432-9542  www.belfuse.com
2
ISOLATED DC/DC CONVERTERS
18 Vdc - 75 Vdc Input 5 Vdc / 8 A Output, 1/16 Brick
Bel Power Inc., a subsidiary of Bel Fuse Inc.
May 24, 2011
Output Specifications (continued)
Parameter
Min
Typ
Max
Unit
8.8
10
12.5
A
Short Circuit Surge Transient
-
0.5
1
As
Turn on Time
-
25
50
mS
Overshoot at Turn on
-
0
5
%
150
-
2200
uF
Overshoot
-
250
350
mV
Settling Time
-
100
200
mS
-
250
350
mV
-
100
200
mS
Output DC Current Limit
Output Capacitance
2
Notes
Hiccup mode, auto
recovery.
Transient Response
25% ~ 50%
Max Load
50% ~ 25%
Max Load
Overshoot
Vo=5 V
Settling Time
di/dt=0.1A/us, Vin=48Vdc,
Ta=25°C, with a 1µF
ceramic capacitor and a
10uF Tantalum cap at
output.
Note: All specifications are typical at nominal input, full load at 25°C unless otherwise stated.
General Specifications
Parameter
Efficiency
Switching Frequency
Over Temperature Protection
Output Voltage Trim Range
Over Voltage Protection
Min
Typ
Max
Unit
85
87
-
%
-
500
-
KHz
-
125
-
C
90
-
110
%
-
130
160
%
Dimensions
1.30 x 0.90 x 0.46
33.02 x 22.86 x 11.69
Inches (L × W × H)
Millimeters (L × W × H)
Weight
Notes
Vin=48 V, full load
The OTP threshold is set at 125C in
non-latch mode, and the module will
restart automatically when
temperature falls down to 115C.
This voltage is achieved by trimming
up output slowly.
-
-
14
-
g
-
-
1500
V
10M
-
-
Ohm
-
3900
-
pF
Isolation characteristics
Input to Output
Isolation Resistance
Isolation Capacitance
Note: All specifications are typical at 25 C unless otherwise stated.
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302  Tel 201-432-0463  Fax 201-432-9542  www.belfuse.com
3
ISOLATED DC/DC CONVERTERS
18 Vdc - 75 Vdc Input 5 Vdc / 8 A Output, 1/16 Brick
Bel Power Inc., a subsidiary of Bel Fuse Inc.
May 24, 2011
Efficiency Data
90%
85%
EFFICIENCY
80%
18V
75%
24V
48V
75V
70%
65%
60%
55%
50%
0.80
2.00
4.00
6.00
8.00
OUTPUT CURRENT (A)
Thermal Derating Curve
Maximum junction temperature of semiconductors derated to 120 degree C.
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302  Tel 201-432-0463  Fax 201-432-9542  www.belfuse.com
4
ISOLATED DC/DC CONVERTERS
18 Vdc - 75 Vdc Input 5 Vdc / 8 A Output, 1/16 Brick
Bel Power Inc., a subsidiary of Bel Fuse Inc.
May 24, 2011
Thermal Derating Curve (continued)
Derating curve under normal input
Vin= 48Vdc
Vin= 24Vdc
The OTP is achieved by thermistor R65 and the threshold is set at 120C in non-latch mode; the hottest
component Q5 reaches 125C with 100LFM air flow correspondingly. It will restart automatically when the
temperature falls down to 115C. The protecting point will be varied a little under different conditions (air flow,
ambient temperature, input voltage, load...).
Temperature reference points on top side
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302  Tel 201-432-0463  Fax 201-432-9542  www.belfuse.com
5
ISOLATED DC/DC CONVERTERS
18 Vdc - 75 Vdc Input 5 Vdc / 8 A Output, 1/16 Brick
Bel Power Inc., a subsidiary of Bel Fuse Inc.
May 24, 2011
Ripple and Noise Waveform
48Vdc input, 5Vdc output
Note: Ripple and noise at full load, with a 1uF ceramic cap and a 10 uF Tantalum cap at output, Ta=25 deg C.
Transient Response Waveforms
Vout= 5V 50%-25% Load Transients
Vout= 5V 25%-50% Load Transients
Note: Transient Response at di/dt=0.1A/uS, Vin=48Vdc, with an External 100uF Tantalum Cap and 1uF Ceramic
Cap, Ta=25 deg C.
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302  Tel 201-432-0463  Fax 201-432-9542  www.belfuse.com
6
ISOLATED DC/DC CONVERTERS
18 Vdc - 75 Vdc Input 5 Vdc / 8 A Output, 1/16 Brick
Bel Power Inc., a subsidiary of Bel Fuse Inc.
May 24, 2011
Startup
Rise time
Start up time
Ch1: Vo
Ch2: Vin
Vin=48V, Vo=5V, 100% Load
Vin=48V, Vo=5V, 100% Load
Note: Start up waveform, tested with an External 220uF Tantalum Cap and 1uF Ceramic Cap, Ta=25 deg C.
Remote On/Off
Parameter
Signal Low (Unit On)
Signal High (Unit Off)
Current Sink
Active Low
-
Min
-0.3
Typ
-
Max
0.8
Unit
V
2.4
-
18
V
0
-
1
mA
Notes
Remote On/Off pin is open,
the module is off.
Recommended remote on/off circuit for active low
Vin+
Vin+
On/off
On/off
Vin-
Vin-
Control with open collector/drain circuit
Control with photocoupler circuit
Vin+
Vin+
On/off
On/off
Vin-
Vin-
Vcc
Control with logic circuit
Permanently on
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302  Tel 201-432-0463  Fax 201-432-9542  www.belfuse.com
7
ISOLATED DC/DC CONVERTERS
18 Vdc - 75 Vdc Input 5 Vdc / 8 A Output, 1/16 Brick
Bel Power Inc., a subsidiary of Bel Fuse Inc.
May 24, 2011
Output Trim Equations
Equations for calculating the trim resistor are shown below (Unit: kΩ). The Trim Down resistor should be
connected between the Trim pin and Ground pin. The Trim Up resistor should be connected between the Trim
pin and the Vout. Only one of the resistors should be used for any given application.
Vout
Rtrimdown 
511
 10 .22 k
delta
Module
Trim
GND
Rtrimdown
Vout
(100  delta)  Vo  5.11  626
Rtrimup 
 10.22 k
1.225 delta
Module
Trim
Rtrimup
GND
Note:
delta 
Vo _ req  Vo   100 %
Vo
400
2500
360
2250
320
2000
Trim resistor value,Rtrim_up(KOhm)
Trim resistor valueRtrim_down(KOhm)
Vo_req=Desired(trimmed) output voltage[V]
Output voltage Vo=5.002V
280
240
200
160
120
80
40
0
1750
1500
1250
1000
750
500
250
4
4.1
4.2
4.3
4.4
4.5
4.6
4.7
Adjusted output voltageVo,adj (V)
4.8
4.9
5
0
5
5.05
5.1
5.15 5.2 5.25 5.3 5.35
Adjusted output voltageVo,adj(V)
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302  Tel 201-432-0463  Fax 201-432-9542  www.belfuse.com
5.4
5.45
8
5.5
ISOLATED DC/DC CONVERTERS
18 Vdc - 75 Vdc Input 5 Vdc / 8 A Output, 1/16 Brick
Bel Power Inc., a subsidiary of Bel Fuse Inc.
May 24, 2011
Remote Sense
This module has remote sense compensation feature. It can minimize the effects of resistance between
module’s output and load in system layout and facilitates accurate voltage regulation at load terminals or
other selected point.
1. The remote sense lines carries very little current and hence do not require a large cross-sectional area.
2. This module compensates for a maximum drop of 10% of the nominal output voltage.
3. If the unit is already trimmed up, the available remote sense compensation range should be
correspondingly reduced. The total voltage increased by trim and remote sense should not exceed 10%
of the nominal output voltage.
4. When using remote sense compensation, all the resistance, parasitic inductance and capacitance of the
system are incorporated within the feedback loop of this module. It can make an effect on the module's
compensation, affecting the stability and dynamic response. A 0.1uF ceramic capacitor can be
connected at the point of load to de-couple noise on the sense wires.
5. Recommend the connection of remote sense compensation as below figure. There are a resistor RS+
(51 ohm) from Vo+ to Sense+ and a resistor RS- (10 ohm)) from Vo- to Sense- inside of this module.
RS+
Vo+
Sense+
Load
RS-
Sense-
V o-
6. If not using remote sense compensation, please connect sense directly to output at module's pin, that is,
connect sense+ to Vo+ and sense- to Vo- at module's pin, the shorter the better. See below figure.
RS+
V o+
Sense+
Load
RS-
Sense-
Vo-
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302  Tel 201-432-0463  Fax 201-432-9542  www.belfuse.com
9
ISOLATED DC/DC CONVERTERS
18 Vdc - 75 Vdc Input 5 Vdc / 8 A Output, 1/16 Brick
Bel Power Inc., a subsidiary of Bel Fuse Inc.
May 24, 2011
Mechanical Outline
Pin Connections
Pin
1
2
3
4
5
6
7
8
Function
Vin (+)
On/Off
Vin (-)
Vout (-)
SENSE(-)
Trim
SENSE(+)
Vout (+)
Dia.
0.04’’
0.04’’
0.04’’
0.062’’
0.04’’
0.04’’
0.04’’
0.062’’
Note: This module is recommended and compatible with Pb-Free Wave Soldering and must be soldered
using a peak solder temperature of no more than 260 ºC for less than 5 seconds.
Note:
1) All Pins: Material - Copper Alloy;
Finish – 3 micro inches minimum Gold over 50 micro inches minimum Nickel plate.
2) Undimensioned components are shown for visual reference only.
3) All dimensions in inches (mm); Tolerances: x.xx +/-0.02 in. (x.x +/-0.5mm) x.xxx +/-0.010 in. (x.xx +/-0.25mm).
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302  Tel 201-432-0463  Fax 201-432-9542  www.belfuse.com
10
ISOLATED DC/DC CONVERTERS
18 Vdc - 75 Vdc Input 5 Vdc / 8 A Output, 1/16 Brick
Bel Power Inc., a subsidiary of Bel Fuse Inc.
May 24, 2011
Revision History
Date
Revision
2011-05-24
PA
Changes Detail
Approval
First release
JZ Wang
RoHS Compliance
Complies with the European Directive 2002/95/EC, calling for the elimination of lead and
other hazardous substances from electronic products.
2011 Bel Fuse Inc. Specifications subject to change without notice. 052411
11
CORPORATE
FAR EAST
EUROPE
Bel Fuse Inc.
206 Van Vorst Street
Jersey City, NJ 07302
Tel 201-432-0463
Fax 201-432-9542
www.belfuse.com
Bel Fuse Ltd.
8F/ 8 Luk Hop Street
San Po Kong
Kowloon, Hong Kong
Tel 852-2328-5515
Fax 852-2352-3706
www.belfuse.com
Bel Fuse Europe Ltd.
Preston Technology Management Centre
Marsh Lane, Suite G7, Preston
Lancashire, PR1 8UD, U.K.
Tel 44-1772-556601
Fax 44-1772-888366
www.belfuse.com