Data Sheet
September 20, 2004
JBW050F Power Modules: dc-dc Converter;
36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
Applications
■Distributed power architectures
■Workstations
■Computer equipment
■Communications eq uipment
Options
■Heat sinks available for extended operation
■Choice of remote on/off logic configuration
■Short Pins: 3.7 mm ± 0.25 mm
(0.145 in ± 0.010 in)
■Approved for basic insulation (-B suffix)
Features
■Small size: 61.0 mm x 57.9 mm x 12.7 mm
(2.40 in. x 2.28 in. x 0.50 in.)
■High power density
■High efficiency: 81% typ ical
■Low output noise
■Constant frequency
■Industry-standard pinout
■Metal case
■2:1 input voltage range
■Overtemperature protection
■Overcurrent and overvoltage protection
■Remote sense
■Remote on/off
■Adjustable output voltage: 60% to 110% of VO, nom
■Case ground pin
■ISO9001 Certified manufacturing fa cilities
■UL* 60950 Recognized, CSA† C22.2 No. 60950-00
Certified, and EN 60950 (VDE0805):2001-12
Licensed
■CE mark meets 73/23/EEC and 93/68/EEC
directives‡
*UL is a registered trademark of Underwriters Laboratories, Inc.
†CSA is a registered trademark of Canadian Standards Assn.
‡This product is intended for integration into end-use equipmen t.
All the required procedures for CE marking of end-use equip-
ment should be followed. (The CE mark is placed on selected
products.)
Description
The JBW050F Power Mo dule is a dc-dc converter that operates over an input voltage range of 36 Vdc to 75
Vdc and provide s a precisely regulated 3.3 Vdc output. The output is fully isolated from the input, allowing a
versatile polarit y con fig uratio n an d ground ing connections. The module has a maximum power rating of 33 W
at a typical full-load efficiency of 81%.
The modules are DC board-mount able and encapsulated in metal cases . Threaded-through hole s are provided to
allow easy mount ing or addit ion o f a h eat sin k for high-temperature applica tions. The standard feature set
includes remote sensing, output trim, and remote on/off f or con venient flexibility in distributed power applications .
The JBW050F Power Module use advanced, surface-mount
technology and deliver high-quality, efficient, and compact
dc-dc conversion.
2Tyco Electronics Power Systems
Data Sheet
September 20, 2004
36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
JBW050F Power Modules: dc-dc Converter;
Absolute Maximum Ratings
Stresses in excess of the absolute maximum ratings can cause permanent damage to t he d evice. These are abso-
lute stress ratings only. Functional operation of the device is not implied at these or any other conditions in excess
of those given in the operations sections of the data sheet. Exposure to absolute maximum ratings for extended
periods can adversely affect device reliability.
Electrical Specifications
Unless otherwise indicated, specifications apply over all operating input voltage, resistive load, and temperature
conditions.
Table 1. Input Specifications
Fusing Considerations
CAUTION: This power module is not internally fused. An input line fuse must always be use d.
This encapsulated power module can be us ed in a wide variety of applications, ranging from simple stand-alone
operation to an integrated part of a sophisticated power architecture. To preserve maximum flexibility, internal fus-
ing is not included; ho w ever, to achieve maximum safety and system protection, alw ays use an input line fuse. The
safety agencies require a fast-acting fuse with a maximum rating of 10 A (see Safety Considerations section).
Based on the information provided in this data sheet on inrush energy and maximum dc input current, the same
type of fuse with a lower rating can be used. Refer to the fuse manufacturer’s data f or further information.
Parameter Symbol Min Max Unit
Input Vo lta ge :
Continuous:
Transient (100 ms) VI
VI, trans —
—75
100 Vdc
V
I/O Isolation Voltage — — 1500 Vdc
Operating Case Temperature
(See Thermal Considerations section.) TC–40 100 °C
Storage Temperatu re Tstg –55 125 °C
Parameter Symbol Min Typ Max Unit
Operat ing Input Voltage VI36 48 75 Vdc
Maximu m Input Current
(VI = 0 V to 75 V; IO = IO, max):
JBW050F (See Figure 1.) II, max ——1.2A
Inrush Transient i2t——1.0A
2s
Input Reflec te d- ripple Curr en t, Peak-to-peak
(5 Hz to 20 MHz, 12 µH source impedance;
see Figure 8.)
II —5—mAp-p
Input Ripple Rejection (120 Hz) — — 60 — dB
Tyco Electronics Power Systems 3
Data Sheet
September 20, 2004 36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
JBW050F Power Modules: dc-dc Converter;
Electrical Specifications (continued)
Table 2. Output Specifications
* Consult your sales representative or the factory.
† These are manufacturing test limits. In some situations, results may differ.
Parameter Symbol Min Typ Max Unit
Output Voltage Set Point
(VI = 48 V; IO = IO, max; TC = 25 °C) VO, set 3.25 3.3 3.35 Vdc
Output Voltage
(Ov er all operating input v oltage, re sistive load,
and temperature conditions until end of life.
See Figure 10. )
VO3.20 — 3.40 Vdc
Output Regulation:
Line (VI = 36 V to 75 V)
Load (IO = IO, min to IO, max )
Temperat ur e (TC = –40 °C to +100 °C)
—
—
—
—
—
—
0.01
0.05
15
0.1
0.2
50
%VO
%VO
mV
Output Ripple and Noise Voltage
(See Figure 9.):
RMS
Peak-to-peak (5 Hz to 20 MHz) —
——
——
—40
150 mVrms
mVp-p
External Load Capacitance — 0 — * µF
Output Current
(At IO < IO, min, the modules may exceed output
ripple specifications.)
IO0.5 — 10 A
Output Current-limit Inception
(VO = 90% of VO, nom)IO, cli —11.414
†A
Output Short-circuit Current (VO = 250 mV) — — 140 — %IO, max
Efficiency (VI = 48 V; IO = IO, max; TC = 70 °C) η—81—%
Switching Frequency — — 330 — kHz
Dynamic Response
(∆IO/∆t = 1 A/10 µs, VI = 48 V, TC = 25 °C;
tested with a 10 µF alu minum and a 1.0 µF
ceramic capacitor across the load):
(see Figure 5 and Figu re 6)
Load Change fr om IO = 50% to 75% of IO, max:
Peak Deviation
Settling Time (VO < 10% of peak deviation)
Load Change fr om IO = 50% to 25% of IO, max:
Peak Deviation
Settling Time (VO < 10% of peak deviation)
—
—
—
—
—
—
—
—
3.8
400
3.8
400
—
—
—
—
%VO, set
µs
%VO, set
µs
4Tyco Electronics Power Systems
Data Sheet
September 20, 2004
36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
JBW050F Power Modules: dc-dc Converter;
Electrical Specifications (continued)
Table 3. Isolation Specifications
General Specifications
Feature Specifications
Unless otherwise indicated, specifications apply over all operating input voltage, resistive load, and temperature
conditions. See Feature Descriptions for additional information.
* These are manufacturing test limits. In some situations, results may differ.
Parameter Min Typ Max Unit
Isolation Capacitance — 2500 — pF
Isolation Resistance 10 — — MΩ
Parameter Min Typ Max Unit
Calculated MTBF (IO = 80% of I O, max; TC = 40 °C) 3,210,000 hr.
Weight — — 100 (3.5) g (oz.)
Parameter Symbol Min Typ Max Unit
Remote On/Off Signal Interface
(VI = 0 V to 75 V; open collector or equivalent compatible;
signal referenced to VI( –) terminal; see Figure 11 and
Feature Descriptions.):
Preferred Logic:
Logic Low—Module On
Logic High—Module Off
Optional Logic:
Logic Low—Module Off
Logic High—Module On Logic Low:
At Ion/off = 1.0 mA
At Von/off = 0.0 V
Logic High:
At Ion/off = 0.0 µA
Leakage Current
Turn-on Time (See Figure 7.)
(IO = 80% of IO, max; VO within ±1% of steady state)
Von/off
Ion/off
Von/off
Ion/off
—
0
—
—
—
—
—
—
—
—
20
1.2
1.0
15
50
35
V
mA
V
µA
ms
Output Voltage Adjustment (See Feature Descriptions.):
Output Voltage Remote-sense Range
Output Voltage Set-point Adjustment Range (trim) —
——
60 —
—0.5
110 V
%VO, nom
Output Overvoltage Protection VO, clamp 3.8* — 5.3* V
Overtemperature Protection (shutdown) TC—105— °C
Data Sheet
September 20, 2004
Tyco Electronics Power Systems 5
36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
JBW050F Power Modules: dc-dc Converter;
Characteristic Curves
The following figures provide typical characteristics for the power modules. The figures are identical for both on/off
configurations.
1-0698
Figure 1. Typical Input Characteristics at Room
Temperature
1-0699
Figure 2. Typical Out put Characteristics at Room
Temperature
1-0700
Figure 3. Typical Converter Efficiency vs. Output
Current at Room Temperature
1-0701
Figure 4. Typical Output Ripple Voltage at Room
Temperature, IO = Full Load
0
0.2
0.4
0.6
0.8
1
1.2
1.4
30 35 40 45 50 55 60 65 70 75
INPUT VOLTAGE, VI (V)
INPUT CURRENT, II (A)
0
0.5
1
1.5
2
2.5
3
3.5
0123456789101112131415
OUTPUT CURRENT, IO
(
A
)
OUTPUT VOLTAGE, VO (V)
70
72
74
76
78
80
82
84
012345678910
VI = 36 V
VI = 48 V
VI = 75 V
OUTPUT CURRENT, IO (A)
EFFICIENCY, η (%)
TIME, t (1 µs/div)
OUTPUT V OLTAGE,
V
O
(V) (20 mV/div)
36 V
48 V
75 V
6Tyco Electronics Power Systems
Data Sheet
September 20, 2004
36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
JBW050F Power Modules: dc-dc Converter;
Characteristic Curves (continuted)
1-0702
Note: Tested with a 10 µF aluminum and a 1.0 µF ceramic capacitor
across the load.
Figure 5. Typical Transient Response to Step
Decrease in Load from 50% to 25% of
Full Load at Room Temperature and 48 V
Input (Waveform Averaged to Eliminate
Ripple Component.)
1-0703
Note: Tested with a 10 µF aluminum and a 1.0 µF ceramic capacitor
across the load.
Figure 6. Typical Transient Response to Step
Increase in Load fr om 50% to 75% of Full
Load at Room Temperature and
48 V Input (Waveform Averaged to
Eliminate Ripple Component.)
1-0704
Note: Tested with a 10 µF aluminum and a 1.0 µF ceramic capacitor
across the load.
Figure 7. Typical Start-Up from Remote On/Off;
IO = IO, max
Test Configurations
8-203.l
Note: Measure input reflected-ripple current with a simulated source
inductance (LTEST) of 12 µH. Capacitor CS offsets possible bat-
tery impedance. Measure current as shown above.
Figure 8. Input Reflected-Ripple Test Setup
TIME, t (100 µs/div)
OUTPUT CURRENT, I
O
(A)
(2 A/div)
OUTPUT V OLTAGE, V
O
(V)
(50 mV/div)
TIME, t (100 µs/div)
OUTPUT CURRENT, I
O
(A)
(2 A/div)
OUTPUT V OLTAGE, V
O
(V)
(50 mV/div)
TIME, t (5 ms/div)
OUTPUT V OLTAGE
V
O
(V) (1 V/div) REMOTE ON/OFF
V
ON/OFF
(V)
T
O
OSC
ILL
OSCO
PE
CURRENT
PROBE
BATTERY
LTEST
12 µH
CS 220 µF
ESR < 0.1 Ω
@ 20 °C, 100 kHz 33 µF
ESR < 0.7 Ω
@ 100 kHz
VI(+)
VI(–)
Data Sheet
September 20, 2004
Tyco Electronics Power Systems 7
36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
JBW050F Power Modules: dc-dc Converter;
Test Configurations (continuted)
8-513.d
Note: Use a 1.0 µF ceramic capacitor and a 10 µF aluminum or tan-
talum capacitor. Scope measurement should be made using a
BNC socket. Position the load between 51 mm and 76 mm
(2 in. and 3 in.) from the module.
Figure 9. Peak-to-Peak Output Noise
Measurement Test Setup
8-749
Note: A ll measurements are taken at the module terminals. When
socketing, place Kelvin connections at module terminals to
avoid measurement errors due to socket contact resistance.
Figure 10. Output Voltage and Efficiency
Measurement Test Setup
Design Considerations
Input Sour ce Impedance
The power module should be connected to a low
ac-impedance input source. Highly inductive source
impedances can affect the stability of the power mod-
ule. For the test configuration in Figure 8, a 33 µF elec-
trolytic capacitor (ESR < 0.7 Ω at 100 kHz) mounted
close to the power module helps ensure stability of the
unit. For other highly inducti ve source impedances,
consult the factory for further application guidelines.
Safety Considerations
For safety-agency approval of the system in which the
power module is used, the power module must be
installed in compliance wit h the spacing and separat ion
requirements of the end-use safety agency standard,
i.e., UL60950, CSA C22.2 No. 60950-00, and
EN 60950 (VDE0805):2001-12.
If the input source is non-SELV (ELV or a hazardous
voltage greater than 60 Vdc and less than or equal to
75 Vdc), for the module’s output to be considered
meeting the requirements of safety extra-low voltage
(SELV), all of the following must be true:
■The input source is to be provided with reinforced
insulation from any hazardous v oltages, including the
ac mains.
■One VI pin and one VO pin are to be grounded or
both the input and output pins are t o be ke pt floating.
■The input pins of th e module are not operator acces-
sible.
■Another SELV reliability test is conducted on the
whole system, as requir ed by the saf ety agencie s, on
the combination of supply source and the subject
module to verify that under a single faul t, hazardous
voltages do not appear at the module’s output.
Note: Do not ground either of the input pins of the
module without grounding one of the output pins.
This may allow a non-SELV voltage to appear
between the output pin and ground.
The pow er modu le has e xt ra-lo w voltage (ELV) outputs
when all inputs are ELV.
The input to these units is to be provided with a maxi-
mum 10 A fast-acting fuse in the ungrounded lead.
1.0 µFRESISTIVE
SCOPE
COPPER STRIP
10 µFLOAD
VO(+)
VO(–)
VI(+)
IIIO
SUPPLY
CONTACT
CONTACT AND
LOAD
SENSE(+)
VI(–)
VO(+)
VO(–)
SENSE(–)
RESISTANCE
DISTRIBUTION LOSSES
ηVO(+) – VO(–)[]IO
VI(+) – VI(–)[]II
------------------------------------------------
x 100 %=
88 Tyco Electronics Power Systems
Data Sheet
September 20, 2004
36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
JBW050F Power Modules: dc-dc Converter;
Feature Descriptions
Overcurrent Protection
To provide protection in a fault (output overload) condi-
tion, the unit is equipped with internal current-limiting
circuitry and can endure current limiting for an unlim-
ited duration. At the point of current -limit inception, the
unit shifts from voltage control to current control. If the
output voltage is pulled very low during a severe fault,
the current- limit circ uit ca n exhibit either foldback or tai-
lout characteristics (output current decrease or
increase). Th e un it op erate s no rma lly onc e th e ou tp ut
current is brou ght back into its specified range.
Remote On/Off
Two remote on/off options are available. Positive logic
remote on/off turns the module on during a logic-high
voltage on the ON/OFF pin, and off during a logic low.
Negative logic remote on/off turns the module off dur-
ing a logic high and on during a logic low. Negative
logic (code suffix “1”) is the factory-preferred configura-
tion.
To turn the power module on and off, the user m ust
supply a switch to control the voltage between the
on/off terminal and the VI(–) terminal (Von/off). The
switch can be an open collector or equivalent (see
Figure 11). A logic low is Von/off = 0 V to 1.2 V. The
maximum Ion/off during a logic low is 1 mA. The switch
should maintain a logic-low voltage while sinking 1 mA.
During a logic high, the maximum Von/off generated by
the power module is 15 V. The maximum allowable
leakage current of the switch at Von/off = 15 V is 50 µA.
If not using the remote on/ off feature, do one of the
following:
■F or negativ e logic, short ON/OFF pin to VI(–).
■For positive logic, leave ON/OFF pin open.
8-720c
Figure 11. Remote On/Off Implementation
Remote Sense
Remote sense minimizes the effects of distribution
losses by re gulating the voltage at the remote-sense
connections. The voltage between the remote-sense
pins and the output terminals must not exceed the out-
put voltage sense r ange given in t he Feature Specifica-
tions table, i.e .:
[VO(+) – VO(–)] – [SENSE(+) – SENSE(–)] ≤ 0.5 V
The voltage between the VO(+) and VO(–) terminals
must not exceed the minimum value of the output over-
voltage protection. This limit includes any increase in
v oltage due to remote-sen se compensa tion and outpu t
voltage set-point adjustment (trim). See Figure 12.
If not using the rem o te- se nse featur e to re gu la te the
output at the poin t of load, then connect SENSE(+) to
VO(+) and SENSE(–) to VO(–) at the module.
Although the out put voltage can be increased by both
the remote sense and by the trim, the maximum
increase for the output voltage is not the sum of both.
The maximum increase is the larger of either the
remote sense or the trim. Consult the factory if you
need to increase the output voltag e more than the
above limitation.
The amount of power delivered by the modu le is
defined as the voltage at the output terminals multiplied
by the output current. When using remote sense and
trim, the output voltage of the module can be
increased, which at the same output current would
increase the power output of the module. Care should
be taken to ensure that the maximum output power of
the module remains at or below the maximum rated
power.
SENSE(+)
VO(+)
SENSE(–)
VO(–)
VI(–)
+
–
Ion/off ON/OFF
VI(+)
LOAD
Von/off
Tyco Electronics Power Systems
Data Sheet
September 20, 2004 36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
JBW050F Power Modules: dc-dc Converter;
Feature Descriptions (continued)
Remote Sense (continued)
8-651m
Figure 12. Effective Circuit Configuration for
Single-Module Remote-Sense Operation
Output Voltage Set-P oint Adjustment (Trim)
Output voltage trim allows the user to increase or
decrease the outp ut v oltage set poin t of a module . This
is accomplished by connecting an external resistor
between the TRIM pin and either the SENSE(+) or
SENSE(–) pins. The trim resistor should be positioned
close to the module.
If not using the trim feature, leave t he TRIM pin open.
With an external resistor between the TRIM and
SENSE(–) pins (Radj-down), the output voltage set point
(VO, adj) decreases (see Figure 13). The following equa-
tion determines the required external-resistor value to
obtain a percentage output voltage change of ∆%.
The test results for this configuration are displayed in
Figure 14. This figure applies to all output voltages.
With an external resistor connected between the TRIM
and SENSE(+) pins (Radj-up), the output voltage set
point (VO, adj) increases (see Figure 15).
The following equation determines the required exter-
nal-resistor v alue to obtain a percentage output v oltage
change of ∆%.
The test results for this configuration are displayed in
Figure 16.
SENSE(+)
SENSE(–)
VI(+)
VI(–)
IOLOAD
CONTACT AND
SUPPLY II
CONTACT
VO(+)
VO(–)
DISTRIBUTION LOSSESRESISTANCE
Radj-down 100
∆%
----------2–
kΩ=
Radj-up VO100 ∆%+()
1.225∆%
-------------------------------------- 100 2∆%+()
∆%
----------------------------------
–
kΩ=
1010 Tyco Electronics Power Systems
Data Sheet
September 20, 2004
36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
JBW050F Power Modules: dc-dc Converter;
The voltage between the VO(+) and VO(–) terminals
must not exceed the minimum value of the output over-
voltage protection. This limit includes any increase in
v oltage due to remote-sen se compensati on and output
voltage set-point adjustment (trim). See Figure 12.
Although the output voltage can be increased by both
the remote sense and by the trim, the maximum
increase for the output voltage is not the sum of both.
The maximum increase is the larger of either the
remote sense or the trim. Consult the f actory if you
need to increase the output voltage more than the
above limitation.
The amount of power delivered by the modu le is
defined as the volta ge at the output t erminals multiplied
by the output current. When using remote sense and
trim, the output voltage of the module can be
increased, which at the same outpu t cu rrent would
increase the power output of the module. Care should
be taken to ensure that the maximum output power of
the module remain s at or below the maximum rated
power.
8-748b
Figure 13. Circuit Configuration to Decrease
Output Voltage
8-879
Figure 14. Resistor Selection for Decreased
Output Voltage
Feature Descriptions (continued)
Output Voltage Set-Point Adjustment
(Trim) (continued)
8-715b
Figure 15. Circ uit Configuration to Increase
Output Voltage
8-2090
Figure 16. Resistor Selection for Increased Output
Voltage
Output Overvoltage Protection
The output overvoltage clamp consists of control cir-
cuitry, independent of the primary regulation loop, that
monitors the voltage on the output terminals. The con-
trol loop of the clamp has a hig her voltage set point
than the primary loop (see Feature Specifications
table). This pro vides a redundant voltage control that
reduces the risk of output overvoltage.
Overtemperature Protection
The module features an ov ertemperature pro tection cir-
cuit to safeguard against thermal damage.
The circuit shuts down the module when the maxim u m
case temperature is exceeded. The module restarts
automatically after cooling.
VI
(+)
VI(–)
ON/OFF
CASE
VO(+)
VO(–)
SENSE(+)
TRIM
SENSE(–) Radj-down RLOAD
100
1k
100k
1M
10k
10 20 30 400
ADJUSTMENT RESISTOR VALUE (Ω)
% CHANGE IN OUTPUT VOLTAGE (∆%)
VI
(+)
VI(–)
ON/OFF
CASE
VO(+)
VO(–)
SENSE(+)
TRIM
SENSE(–)
Radj-up RLOAD
246
10k
100k
% CHANGE IN OUTPUT VOLTAGE ( %)
10M
100
1M
8
ADJUSTMENT RESISTOR VALUE ( )
Tyco Electronics Power Systems
Data Sheet
September 20, 2004 36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
JBW050F Power Modules: dc-dc Converter;
Thermal Considerations
Introduction
The power modules oper ate in a variety of thermal
environments; however, sufficient cooling should be
prov ided to help ensure reliable operation of the unit.
Heat-dissipating components inside the unit are ther-
mally coupled to the cas e. Heat is removed by conduc-
tion, convection, and radiation to the surrounding
environment. Proper cooling can be verified by mea-
suring the case temperature. Peak temperature (TC)
occurs at the position indicated in Figure 17.
8-716.f
Note: Top view, pin locations are for reference only.
Measurements shown in millimeters and (inches).
Figure 17. Case Temperature Measurement
Location
The temperature at this location should not exceed
100 °C. The output power of the module should not
exceed the rated power for the module as listed in the
Order i n g In formation table.
Although the maximum case temperature of the power
modules is 100 °C, you can limit this temperature to a
lower value for extremely high reliability.
Note that although the maximum case temperature
allowed is lower than 100 °C under some conditions,
this modules der ating is equiv a lent to or bett er than the
JW050F. At full load, the JW050F power module has a
higher case temperature rise than the JBW050F.
For additional information on these modules, refer to
the Thermal Management JC-, JFC-, JW-, and JFW-
Series 50 W to 150 W Board-Mounted Power Modules
Technical Note (TN97-008EPS).
Thermal Considerations (continued)
Heat Transfer Without Heat Sinks
Increasing airflow over the module enhances the heat
transfer via convection. Figure 19 shows the maximum
power that can be dissipated by the module without
e xceeding the maximum case temperature v ersus local
ambient temperature (TA) for natural convection
through 3 m/s (600 ft./min.).
Note that the natural con vection condition was mea-
sured at 0.05 m/s to 0.1 m/s (10 ft./min. to 20 ft./min.);
however, systems in which these power modules may
be used can typically
generat e natural convection airflow rat es of 0.3 m/s
(60 ft./min.) due to other heat dissipating components
in the system. The use of Figure 19 is shown in the
following ex ample.
Example
What is the minimum air flow nece ssary for a JBW050F
operatin g at VI = 54 V, an output current of 10 A, and a
maximum ambient temperature of 70 °C?
Solution
Given: VI = 54 V
IO = 10 A
TA = 70 °C
Determine P D (Use Figure 18):
PD = 7.7 W
Determine airflow (v) (Use Figure 19):
v = 0.5 m/s (100 ft./min.)
1-0706
Figure 18. Power Dissipation vs. Output Current
CASE
38.0 (1.50)
MEASU R E CASE
VI(–)
ON/OFF + SEN
TRIM
– SEN
VI(+)
VO(–)
VO(+)
38.0
TEMPERATURE
(1.50)
HERE
0
1
2
3
4
5
6
7
8
9
10
012345678910
VI = 36 V
VI = 48 V
VI = 75 V
OUTPUT CURRENT, IO (A)
POWER DISSIPATION, PD (W)
1212 Tyco Electronics Power Systems
Data Sheet
September 20, 2004
36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
JBW050F Power Modules: dc-dc Converter;
1-0705
Figure 19. Forced Convection Power Derating with
No Heat Sink; Either Orientation
Heat Transfer with Heat Sinks
The power modules have through-threaded, M3 x 0.5
mounting holes , which enab le heat sinks or cold plate s
to attach to the module. The mounting torque must not
exceed 0.5 6 N-m (5 in.-lb.) . For a screw attachment
from the pin side, the recomme nded hole size on the
customer’s PWB around the mounting holes is
0.130 ± 0.005 inches. If a larger hole is used, the
mounting torque from the pin side must not exceed
0.25 N-m (2.2 in.-lb.).
Thermal derating with heat sinks is e xpressed by using
the overall thermal resistance of the module. Total
module thermal resistance (θca) is defin ed as the max-
imum case temperature rise (∆TC, max) divided by the
module power dissipation (PD):
The location to measure case temperature ( TC) is
shown in Figure 17. Case-to-ambient thermal resis-
tance vs. airflow is shown, for various heat sink config-
uration s and heights, in Figure 20. These curves were
obtained by experimental testing of heat sinks, which
are offered in the product catalo g.
Thermal Considerations (continued)
Heat Transfer with Heat Sinks (continued)
8-1052.a
Figure 20. Case-to-Ambient Thermal Resistance
Curves; Either Orientation
These measured resistances are from heat transfer
from the sides and bo ttom of the modul e as w ell as t he
top side with the attached heat sink; therefore, the
case-to-ambient thermal resistances shown are gener-
ally lower than the resistance of the heat sink by itself.
The module used to collect the data in Figure 20 had a
thermal-conductive dry pad between the case and the
heat sink to minimize contact resistance. The use of
Figure 20 is shown in the following example.
Example
If an 85 °C case temperature is desired, what is the
minimum airflow necessary? Assume the JBW050F
module is operating at VI = 54 V and an output current
of 10 A, maximum ambient air temperature of 70 °C,
and the heat sink is 1/ 2 inch.
Solution
Given: VI = 54 V
IO = 10 A
TA = 70 °C
TC = 85 °C
Heat sink = 1/2 in.
Determine P D by using Figure 18:
PD = 7.7 W
Then solv e the following equation:
0
2
4
6
8
10
12
0 20 40 60 80 100 120
LOCAL AMBIENT TEMPERATURE, TA
(
˚C
)
POWER DISSIPATION, PD (W)
MAX CASE TEMP
3.0 m/s (600 ft./min.)
2.0 m/s (400 ft./min.)
1.0 m/s (200 ft./min.)
0.5 m/s (100 ft./min.)
0.25 m/s (50 ft./min.)
NATURAL CONVECTION
θca ∆TCmax,
PD
---------------------TCTA–()
PD
------------------------
==
00.25
(50) 0.51
(100) 0.76
(150) 1.02
(200) 1.78
(350) 2.03
(400)
0
5
6
7
8
AIR VELOCITY, ms-1 (ft./min.)
4
3
2
1
1.27
(250) 1.52
(300)
NO HEAT S INK
1/4 in. HEAT SINK
1/2 in. HEAT SINK
1 in. HEAT SINK
1 1/2 in. HEAT SINK
CASE-TO-AMBIENT THERMAL
RESISTANCE, CA (°C/W)
θca TCTA
–
PD
--------------------
=
θca 85 70–
7.7
------------------
=
θca 1.95 °C/W=
Tyco Electronics Power Systems
Data Sheet
September 20, 2004 36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
JBW050F Power Modules: dc-dc Converter;
Use Figure 20 to determine air velocity for the 1/2 inch heat sink.
The minimum airflow necessary for the JBW050F
module is 1.27 m/s (250 ft./min.).
Custom Heat Sinks
A more detailed model can be used to determine the required thermal resistance of a heat sink to provide neces-
sary cooling. The total module resistance can be separated into a resistance from case- to-sink (θcs) and sink-to-
ambient (θsa) sh own below (Figure 21).
8-1304
Figure 21. Resistance from Case-to-Sink and
Sink-to-Ambient
F or a managed interf ace using thermal grease or f oils , a va lue of θcs = 0.1 °C/W to 0.3 °C/W is typical. The solution
for heat sink resistance is:
This equation assumes tha t all dissipated power must be shed by the heat sink. Depending on t he user-defined
application environment, a more accurate model, includin g heat transfer from the sides and bot tom of the module,
can be used. This equation provides a conservative estimate for such instances.
Solder, Cleaning, and Drying Considerations
Post solder cleaning is usually the final circu it-boar d assembly process prior to electrical testing. The result o f inad-
equate circuit-board cleaning and drying can affect both the reliability of a power module and the testability of the
finished circuit-board assembly. For guidance on appropriate soldering, cleaning, and drying procedures, refer to
the Board-Mounted Power Modules Soldering and Cleaning Application Note (AP01-056EPS).
EMC Considerations
For assistance with de sig nin g for EMC compliance, please refer to the FLTR100V 10 da ta sh ee t
(FDS01-043EPS).
Layout Considerations
Copper paths must not be routed beneath the power module mounting inserts. For additional layout guidelines,
refer to the FLTR100V10 data sheet
(FDS01-043EPS).
PDTCTSTA
θcs θsa
θsa TCTA–()
PD
-------------------------θcs–=
1414 Tyco Electronics Power Systems
Data Sheet
September 20, 2004
36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
JBW050F Power Modules: dc-dc Converter;
Outline Diagram
Dimensions are in millimeters and (inches).
Tolerances: x.x mm ± 0.5 mm (x.xx in. ± 0.02 in.)
x.xx mm ± 0.25 mm (x.xxx in. ± 0.010 in.)
Top View
Note:Pinout marking for reference only
Side View
Bottom View
1-0715
57.9 (2.28) MAX
61.0
(2.40)
MAX
V
I
(-)
ON/
OFF
CASE
+ SEN
TRIM
- SEN
V
I
(+)
V
O
(-)
V
O
(+)
0.51 (0.020)
5.1 (0.20)
MIN
12.7 (0.50)
MAX 2.06 (0.081) DIA
SOLDER-PLATED BRASS,
2 PLACES (-OUTPUT
AND +OUTPUT)
1.02 (0.040) DIA
SOLDER-PLATED
BRASS, 7 PLACES
10.16
(0.400) 17.78
(0.700)25.40
(1.000)35.56
(1.400)
5
6
7
8
9
MOUNTING INSERTS
M3 x 0.5 THROUGH,
4 PLACES
10.16
(0.400)
25.40
(1.000)
50.8
(2.00)
35.56
(1.400)
5.1 (0.20)
4
3
2
1
12.7 (0.50)
4.8
(0.19)
48.26 (1.900)
TERMINALS
48.3 (1.90)
STANDOFF,
4 PLACES
7.1 (0.28)
7.1
(0.28)
MOUNTING HOLES
Tyco Electronics Power Systems
Data Sheet
September 20, 2004 36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
JBW050F Power Modules: dc-dc Converter;
Recommended Hole Pattern
Component-side footprint.
Dimensions are in millimeters and (inches).
8-1945a
Ordering Information
Table 4. Device Codes
Table 5. Device Options
* Contact Tyco Electronics Sales Representatives for
availability of these options, samples, minimum order
quantity and lead times.
** When adding multiple opti on s to the pr od uct code,
add suffix numbers in the descending orders.
10.16
(0.400)
10.16
(0.400)
12.7 (0.50)
48.26
(1.900)
4.8
(0.19)
MOUNTING INSERTS
MODULE OUTLINE
5.1 (0.20)
57.9 (2.28) MAX
17.78
(0.700)
25.40
(1.000)
35.56
(1.400)
25.40
(1.000)
50.8
(2.00)
35.56
(1.400)
61.0
(2.40)
MAX
–SEN
TRIM
+SEN
CASE
ON/OFF
VI (+) VO (+)
48.3 (1.90)
VI (–) Vo (–)
Input
Voltage Output
Voltage Output
Power Remote On/Off
Logic Device
Code Comcode
48 V 3.3 V 33 W Negative JBW050F1 TBD
48 V 3.3 V 33 W Positive JBW050F 108966052
Option* Device Code Suffix **
Short pins: 3.68 mm ± 0.25 mm
(0.145 in. ± 0.010 in.) 6
Approved for basic insulation -B
Data Sheet
September 20, 2004
36 to 75 Vdc Input, 3.3 Vdc Output; 33 W
JBW050F Power Modules: dc-dc Converter;
Tyco Electronics Corporation reserves the right to make changes to the product(s) or information contained herein without notice. No liability is assumed as a result of their use or application.
No rights under any patent accompany the sale of any such product(s) or information.
© 2002 Tyco Electronics Power Systems, Inc. (Mesquite, Texas) All International Rights Reserved.
Printed in U.S.A.
September 20, 2004
FDS02-038EPS (Replaces ADS02-013EPS)
World Wide Headquarters
Tyco E lec tronics Power Systems, Inc.
3000 Skyline Drive, Mesquite, TX 75149, USA
+1-800-526-7819
(Outside U.S.A.: +1-972-284-2626, FAX: +1-972-284-2900)
www.power.tycoelectronics.com
e-mail: techsupport1@tycoelectronics.com
Europe, Mi ddle-East and Africa Headquarters
Tyco Electronics (UK) Ltd
Tel: +44 1344 469 300, F ax: +44 1344 469 301
Caribbean-Latin America-Brazil Headquarters
Tyco Electronics Power Systems
Tel: +56 2 209 8211, Fax: +56 2 223 1477
Asia-Pacific Headquarters
Tyco Electronics Singapore Pte Ltd
Tel: +65 6416 4283, Fax: 65 6416 4299
India Headquarters
Tyco Electronics Systems India Pte Ltd
Tel: +91 80 841 1633 x3001
Ordering Information (continued)
Table 6. Device Accessories
Dimensions are in millimeters and (inches).
D000c
Figure 22. Longitudinal Heat Sink
D000-d.cvs
Figure 23. Transverse Heat Sink
Accessory Comcode
1/4 in. transvers e kit (heat sink, thermal pad, and screws) 407243989
1/4 in. longitudinal kit (heat sink, thermal pad, and screws) 407243997
1/2 in. transvers e kit (heat sink, thermal pad, and screws) 407244706
1/2 in. longitudinal kit (heat sink, thermal pad, and screws) 407244714
1 in. transverse kit (heat sink, thermal pad, and screws) 407244722
1 in. longitudinal kit (heat sink, thermal pad, and screws) 407244730
1 1/2 in. transverse kit (heat sink, thermal pad, and screws) 407244748
1 1/2 in. longitudinal kit (heat sink, thermal pad, and screws) 407244755
57.9 (2.28)
61
(2.4)
1 IN.
1 1/2 IN.
1/4 IN.
1/2 IN.
