LW025G - GE Critical Power - Datasheet.Directory

2 Tyco Electronics

Data Sheet

March 22, 2000

36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Absolute Maximum Ratings

Stresses in excess of the absolute maximum ratings can cause permanent damage to the devices. These are

absolute stress ratings only. Functional operation of the devices 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.

* Maximum case temperature varies based on power dissipation. See derating curves, Figures 24—25, for details.

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 used.

This encapsulated power module can be used 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, always use an input line fuse . The

safety agencies require a normal-blow fuse with a maximum rating of 5 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 for further information.

Parameter Symbol Min Max Unit

Input Voltage:

Continuous

Transient (100 ms) V

I

V

I, trans

0

080

100 Vdc

V

Operating Case Temperature

(See Thermal Considerations section.) T

C

–40 110*

°

C

Storage Temperature T

stg

–55 125

°

C

I/O Isolation Voltage (for 1 minute) — — 1500 Vdc

Parameter Symbol Min Typ Max Unit

Operating Input Voltage V

I

36 48 75 Vdc

Maximum Input Current

(V

I

= 0 V to V

I, max

; I

O

= I

O, max

; see Figures 1—3.) I

I, max

— — 1.2 A

Inrush Transient i

2

t — — 0.1 A

2

s

Input Reﬂected-ripple Current

(50 Hz to 20 MHz; 12

µ

H source impedance,

T

C

= 25

°

C; see Figure 19.)

I

— 3 — mAp-p

Input Ripple Rejection (100 Hz—120 Hz) — — 60 — dB

Tyco Electronics 3

Data Sheet

March 22, 2000 36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Electrical Speciﬁcations

(continued)

Table 2. Output Speciﬁcations

Parameter Device Code

or Sufﬁx Symbol Min Typ Max Unit

Output Voltage Set Point

(V

I

= 48 V; I

O

= I

O, max

; T

C

= 25

°

C) LW025D

LW025G

LW025F

LW025A

V

O, set

V

O, set

V

O, set

V

O, set

1.97

2.46

3.25

4.92

2.0

2.5

3.3

5.0

2.03

2.54

3.35

5.08

Vdc

Output Voltage

(Over all line, load, and temperature

conditions until end of life; see Figure 21.)

LW025D

LW025G

LW025F

LW025A

V

O

V

O

V

O

V

O

1.92

2.40

3.17

4.85

—

2.08

2.60

3.43

5.15

Vdc

Output Regulation:

Line (V

I

= 36 V to 75 V)

Load (I

O

= I

O, min

to I

O, max

)

Temperature (T

C

= –40

°

C to +100

°

C)

A, D, F

G

D

G

A, F

All

—

0.01

0.15

0.3

0.2

0.05

0.5

0.1

0.3

0.5

0.7

0.4

1.0

%V

O

%V

O

%V

O

%V

O

%V

O

%V

O

Output Ripple and Noise (See Figure 20.):

RMS

Peak-to-peak (5 Hz to 20 MHz) All

All —

——

20 40

100 mVrms

mVp-p

Output Current

(At I

O

< I

O , min

, the modules ma y e xceed output

ripple and regulation speciﬁcations.)

All I

O

0.4 — 5.0 A

Output Current-limit Inception

(V

O

= 90% x V

O, set

; see Figures 4—7.) All I

O

103 — 150 %I

O, max

Output Short-circuit Current (V

O

= 250 mV) D

A, F, G I

O

I

O

—

—150

135 220

200 %I

O, max

%I

O, max

Efﬁciency

(V

I

= V

I, nom

; I

O

= I

O , max

; T

C

= 25

°

C; see Figures

8—11 and 21.)

LW025D

LW025G

LW025F

LW025A

η

67

70.5

75

77

69

73.25

77

79

—

%

Switching Frequency All — — 256 — kHz

Dynamic Response

(

∆

I

O

/

∆

t = 1 A/10

µ

s, V

I

= V

I, nom

, T

A

= 25

°

C):

Load Change from I

O = 50% to 75% of IO , max:

Peak Deviation

Settling Time (VO < 10% peak deviation)

Load Change from IO = 50% to 25% of IO , max:

Peak Deviation

Settling Time (VO < 10% peak deviation)

D

G

A, F

All

D

G

A, F

All

—

6

3

2

1

6

3

2

1

—

%VO, set

ms

%VO, set

ms

4 Tyco Electronics

Data Sheet

March 22, 2000

36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Electrical Speciﬁcations (continued)

Table 3. Isolation Speciﬁcations

General Speciﬁcations

Parameter Min Typ Max Unit

Isolation Capacitance — 0.002 — µF

Isolation Resistance 10 — — MΩ

Parameter Min Typ Max Unit

Calculated MTBF (IO = 80% of IO, max; TC = 40 °C) 3,900,000 hours

Weight — — 54 (1.9) g (oz.)

Tyco Electronics 5

Data Sheet

March 22, 2000 36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Feature Speciﬁcations

Unless otherwise indicated, speciﬁcations apply over all operating input voltage, resistive load, and temperature

conditions. See Feature Descriptions and Design Considerations for further information.

Parameter Device Symbol Min Typ Max Unit

Remote On/Off Signal Interface:

(VI = 0 V to VI, max; open collector or equivalent

compatible; signal referenced to VI(–) terminal. See

Figure 22 and Feature Descriptions.):

Negative Logic: Device Code Sufﬁx “1”:

Logic Low—Module On

Logic High—Module Off

Positive Logic: If Device Code Sufﬁx “1” Is Not

Speciﬁed:

Logic Low—Module Off

Logic High—Module On

Module Speciﬁcations:

On/Off Current:

Logic Low

On/Off Voltage:

Logic Low

Logic High (Ion/off = 0)

Open Collector Switch Speciﬁcations:

Leakage Current During Logic High

(Von/off = 10 V)

Output Low Voltage During Logic Low

(Ion/off = 1 mA)

All

Ion/off

Von/off

Ion/off

Von/off

—

–0.7

—

1.0

1.2

10

50

1.2

mA

V

µA

V

Turn-on Delay and Rise Times

(at 80% of IO, max; T A = 25 °C):

Case 1: On/Off Input Is Set for Unit On and Then

Input Power Is Applied (delay from point at which

VI = 48 V until VO = 10% of VO, nom).

Case 2: 48 V Input Is Applied for at Least One

Second, and Then the On/Off Input Is Set to Turn

the Module On (delay from point at which on/off

input is toggled until VO = 10% of VO, nom).

Output Voltage Rise Time (time for VO to rise from

10% of VO, nom to 90% of VO, nom)

Output Voltage Overshoot (at 80% of IO, max;

TA = 25 °C)

All

Tdelay

Trise

—

27

2

1.5

—

50

10

3.0

5

ms

%

Output Voltage Set-point Adjustment Range All — 90 — 110 %VO, nom

Output Overvoltage Protection (clamp) LW025D

LW025G

LW025F

LW025A

VO, clamp

2.6

2.9

3.9

5.6

—

3.5

3.8

5.0

7.0

V

6 Tyco Electronics

Data Sheet

March 22, 2000

36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Characteristics Curves

8-2560(C)

Figure 1. LW025D, G Typical Input Characteristics

8-2233(C)

Figure 2. LW025F Typical Input Characteristics

8-1982(C).b

Figure 3. LW025A Typical Input Characteristics

8-2667(C)

Figure 4. LW025D Typical Output Characteristics

0.2

0.0

0.4

0.6

0.7

0.1

0.3

0.5

10 20 30 70

40 80

0

INPUT CURRENT, I

I

(A)

60

50

INPUT VOLTAGE, V

I

(V)

I

O

= 5.0 A

I

O

= 2.6 A

I

O

= 0.4 A

10 20 30 40 50 60

0.0

INPUT VOLTAGE, V

I

(V)

0.8

INPUT CURRENT, I

I

(A)

800

0.5

0.2

0.4

0.3

70

0.1

I

O

= 5 A

I

O

= 2.5 A

I

O

= 0.4 A

0.6

0.7

10 20 30 40 50 60

0.0

INPUT VOLTAGE, V

I

(V)

0.8

0.6

INPUT CURRENT, I

I

(A)

1.2

800

0.4

70

0.2

1.0

I

O

= 2.5 A

I

O

= 5 A

I

O

= 0.4 A

123456

0.0

1.5

OUTPUT CURRENT, I

O

(A)

1.0

2.0

90

0.5

78

2.5

OUTPUT VOLTAGE, V

O

(V)

V

I

= 36 V

V

I

= 48 V

V

I

= 75 V

Tyco Electronics 7

Data Sheet

March 22, 2000 36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Characteristics Curves (continued)

8-2666(C)

Figure 5. LW025G Typical Output Characteristics

8-2234(C)

Figure 6. LW025F Typical Output Characteristics

123456

0.0

1.5

OUTPUT CURRENT, I

O

(A)

1.0

2.0

90

0.5

78

2.5

3.0

OUTPUT VOLTAGE, V

O

(V)

V

I

= 36 V

V

I

= 48 V

V

I

= 75 V

123456

0.0

OUTPUT CURRENT, I

O

(A)

3.5

OUTPUT VOLTAGE, V

O

(V)

80

2.0

0.5

1.5

1.0

7

V

I

= 36 V

V

I

= 48 V

V

I

= 75 V

2.5

3.0

8-1983(C)

Figure 7. LW025A Typical Output Characteristics

8-2650(C)

Figure 8. LW025D Typical Converter Efﬁciency vs.

Output Current

123456

0

OUTPUT CURRENT, I

O

(A)

4

3

OUTPUT VOLTAGE, V

O

(V)

6

70

2

1

5

V

I

= 48 V

V

I

= 36 V

V

I

= 75 V

0.9 1.4 1.9 2.4 2.9

30

OUTPUT CURRENT, I

O

(A)

65

70

75

0.4

50

55

60

EFFICIENCY, (%)

3.4 3.9 4.4 4.9

45

40

35

V

I

= 75 V

V

I

= 48 V

V

I

= 36 V

88 Tyco Electronics

Data Sheet

March 22, 2000

36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Characteristics Curves (continued)

8-2646(C)

Figure 9. LW025G Typical Converter Efﬁciency vs.

Output Current

8-2478(C)

Figure 10. LW025F Typical Converter Efﬁciency vs.

Output Current

8-1984(C)

Figure 11. LW025A Typical Converter Efﬁciency vs.

Output Current

8-1261(C).f

Figure 12. LW025D Typical Output Voltage for a

Step Load Change from 50% to 25%

0.9 1.4 1.9 2.4 2.9

60

OUTPUT CURRENT, I

O

(A)

68

70

76

0.4

62

64

66

EFFICIENCY, (%)

3.4 3.9 4.4 4.9

V

I

= 75 V

V

I

= 48 V

V

I

= 36 V

72

74

0.9 1.4 1.9 2.4 2.9 3.4

60

76

OUTPUT CURRENT, I

O

(A)

72

70

74

78

0.4

62

68

EFFICIENCY, (%)

3.9 4.4 4.9

66

64

V

I

= 36 V

V

I

= 48 V

V

I

= 75 V

1.0 1.5 2.0 2.5 3.0 3.5

60

OUTPUT CURRENT, I

O

(A)

80

75

EFFICIENCY, (%)

85

5.00.5

70

4.0 4.5

65

V

I

= 48 V

V

I

= 75 V

V

I

= 36 V

TIME, t (100 µs/div)

OUTPUT CURRENT, I

O

(A)

(1.25 A/div) OUTPUT VOLTAGE, V

O

(V)

1.25 A

2.5 A

106%

100%

Tyco Electronics 9

Data Sheet

March 22, 2000 36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Characteristics Curves (continued)

8-1261(C).g

Figure 13. LW025G Typical Output Voltage for a

Step Load Change from 50% to 25%

8-1261(C).h

Figure 14. LW025A, F Typical Output Voltage for a

Step Load Change from 50% to 25%

8-1262(C).f

Figure 15. LW025D Typical Output Voltage for a

Step Load Change from 50% to 75%

8-1262(C).g

Figure 16. LW025G Typical Output Voltage for a

Step Load Change from 50% to 75%

TIME, t (100 µs/div)

OUTPUT CURRENT, IO (A)

(1.25 A/div) OUTPUT VOLTAGE, VO (V)

1.25 A

2.5 A

103%

100%

TIME, t (100 µs/div)

OUTPUT CURRENT, IO (A)

(1.25 A/div) OUTPUT VOLTAGE, VO (V)

1.25 A

2.5 A

102%

100%

OUTPUT CURRENT, IO (A)

(1.25 A/div) OUTPUT VOLTAGE, VO (V)

TIME, t (100 µs/div)

2.5 A

3.75 A

100%

94%

OUTPUT CURRENT, IO (A)

(1.25 A/div) OUTPUT VOLTAGE, VO (V)

TIME, t (100 µs/div)

2.5 A

3.75 A

100%

97%

10 Tyco Electronics

Data Sheet

March 22, 2000

36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Characteristics Curves (continued)

8-1262(C).h

Figure 17. LW025A, F Typical Output Voltage for a

Step Load Change from 50% to 75%

8-1263(C).e

Figure 18. LW025A, D, F, G Typical Output Voltage

Start-Up when Signal Is Applied to

Remote On/Off

Test Conﬁgurations

8-203(C)

Note: Input reﬂected-ripple current is measured with a simulated

source impedance of 12 µH. Capacitor Cs offsets possible

battery impedance. Current is measured at the input of the

module.

Figure 19. Input Reﬂected-Ripple Test Setup

8-513(C)

Note: Use a 0.1 µF ceramic capacitor. Scope measurement should

be made using a BNC socket. Position the load between

50 mm and 75 mm (2 in. and 3 in.) from the module.

Figure 20. Peak-to-Peak Output Noise

Measurement Test Setup

8-204(C)

Note: All 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 21. Output Voltage and Efﬁciency

Measurement Test Setup

OUTPUT CURRENT, IO (A)

(1.25 A/div) OUTPUT VOLTAGE, VO (V)

TIME, t (100 µs/div)

2.5 A

3.75 A

100%

98%

TIME, t (1 ms/div)

0

5 V

NORMALIZED

OUTPUT VOLTAGE, V

O

0

REMOTE ON/OFF,

V

on/off

(V) (2 V/div)

12 µH

C

S

220 µF

IMPEDANCE < 0.1 Ω

@ 20 °C, 100 kHz

V

I

(+)

V

I

(–)

33 µF

CURRENT

PROBE

L

TEST

TO

OSCILLOSCOPE

BATTERY

V

O

(+)

V

O

(–)

RESISTIVE

LOAD

SCOPE

0.1 µF

COPPER STRIP

V

I

(+)

V

I

(–)

V

O

(+)

V

O

(–)

I

O

SUPPLY

CONTACT RESISTANCE

CONTACT AND

DISTRIBUTION LOSSES

LOAD

ηVO(+) VO(–)–[]IO

VI(+) VI(–)–[]II

------------------------------------------------





100

×=%

Tyco Electronics 11

Data Sheet

March 22, 2000 36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Design Considerations

Grounding Considerations

For modules without the isolated case ground pin

option, the case is internally connected to the V I(+) pin.

For modules with the isolated case ground pin, device

code sufﬁx “7,” the VI(+) pin is not connected to the

case.

Input Source 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 19, a 33 µF

electrolytic capacitor (ESR < 0.7 Ω at 100 kHz)

mounted close to the power module helps ensure sta-

bility of the unit. For other highly inductive 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 with the spacing and separation

requirements of the end-use safety agency standard,

i.e.,

UL

1950,

CSA

C22.2 No. 950-95, and

VDE

0805

(EN60950, IEC950).

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 other hazardous voltages, includ-

ing the ac mains; and

■One VI pin and one V O pin are to be grounded or both

the input and output pins are to be kept ﬂoating; and

■The input pins of the module are not operator acces-

sible; and

■Another SELV reliability test is conducted on the

whole system, as required by the saf ety agencies, on

the combination of supply source and the subject

module to verify that under a single fault, 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 pins and ground.

The power module has extra-low v oltage (ELV) outputs

when all inputs are ELV.

The input to these units is to be provided with a maxi-

mum 5 A normal-blow fuse in the ungrounded lead.

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 circuit can exhibit either foldback or

tailout characteristics (output-current decrease or

increase). The unit operates normally once the output

current is brought 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 REMOTE ON/OFF pin, and off during a

logic low. Negative logic, device code sufﬁx “1,” remote

on/off turns the module off during a logic high and on

during a logic low.

To turn the power module on and off, the user must

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 Fig-

ure 22). A logic low is Von/off = –0.7 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 6 V. The maximum allowable leak-

age current of the switch at Von/off = 6 V is 50 µA.

The module has internal capacitance to reduce noise

at the ON/OFF pin. Additional capacitance is not gen-

erally needed and may degrade the start-up character-

istics of the module.

12 Tyco Electronics

Data Sheet

March 22, 2000

36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Feature Descriptions (continued)

Remote On/Off (continued)

8-758(C).a

Figure 22. Remote On/Off Implementation

Output V oltage Adjustment

Output voltage trim allows the user to increase or decrease the output voltage set point of a module. This is accom-

plished by connecting an external resistor between the TRIM pin and either the VO(+) or VO(–) pins. With an exter-

nal resistor between the TRIM and VO(+) pins (Radj-down), the output voltage set point (VO, adj) decreases. With an

external resistor between the TRIM pin and VO(–) pin (Radj-up), V O, adj increases.

The following equations determine the required external resistor value to obtain an output voltage change of ∆%:

The adjusted output voltage cannot exceed 110% of the nominal output voltage between the VO(+) and VO(–)

terminal.

The modules have a ﬁxed current-limit set point. Therefore, as the output voltage is adjusted down, the available

output power is reduced. In addition, the minimum output current is a function of the output voltage. As the output

voltage is adjusted down, the minimum required output current can increase.

Device abcd–5% VO Radj-down +5% VO Radj-up

LW025D 5.11 2.05 3.13 1.63 32.3 kΩ60.6 kΩ

LW025G 14.0 51.1 6.86 2.04 77.6 kΩ86.2 kΩ

LW025F 14.0 51.1 5.2 2.7 111.7 kΩ52.7 kΩ

LW025A 4.02 16.9 2.01 2.0 19.3 kΩ23.3 kΩ

+

I

on/off

–

V

on/off

REMOTE

ON/OFF

V

I

(+)

V

I

(–)

Radj-down cd 1 ∆%–()1–⋅[]

∆%

------------------------------------------------ b–kΩ=

Radj-up a

d∆⋅ %

-----------------b–kΩ=

Tyco Electronics 13

Data Sheet

March 22, 2000 36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Feature Descriptions (continued)

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 protection circuit has a higher voltage

set point than the primary loop (see Feature Speciﬁca-

tions table). In a fault condition, the overvoltage clamp

ensures that the output voltage does not exceed VO,

clamp, max. This provides a redundant v oltage-control that

reduces the risk of output overvoltage.

Synchronization (Optional)

The unit is capable of external synchronization from an

independent time base with a switching rate of

256 kHz. The amplitude of the synchronizing pulse

train is TTL compatible and the duty cycle ranges

between 40% and 60%. Synchronization is referenced

to VI(+).

Thermal Considerations

Introduction

The LW025 Single-Output-Series P o w er Modules oper-

ate in a variety of thermal environments; however, sufﬁ-

cient cooling should be provided to help ensure reliab le

operation of the unit. Heat-dissipating components

inside the unit are thermally coupled to the case. Heat

is removed by conduction, convection, and radiation to

the surrounding environment. Proper cooling can be

veriﬁed b y measuring the case temperature. P eak case

temperature (TC) occurs at the position indicated in Fig-

ure 23.

8-1265(C).c

Note: Dimensions are in millimeters and (inches). Pin locations are

for reference only.

Figure 23. Case Temperature Measurement

Location

Note that the view in Figure 23 is of the metal surface

of the module—the pin locations shown are for refer-

ence. The temperature at this location should not

exceed the maximum case temperature indicated in

the derating curves shown in Figures 24—25. The out-

put power of the module should not exceed the rated

power for the module as listed in the Ordering Informa-

tion table.

Heat T ransfer

Increasing airﬂow over the module enhances the heat

transfer via convection. Figures 24—25 show the maxi-

mum power that can be dissipated by the modules

without exceeding the maximum case temperature ver-

sus local ambient temperature (TA) for natural convec-

tion through 3.0 ms–1 (600 ft./min.).

Systems in which these power modules may be used

typically generate natural convection airﬂow rates of

0.3 ms–1 (60 ft./min.) due to other heat-dissipating

components in the system. Therefore, the natural con-

vection condition represents airﬂow rates of up to

0.3 ms–1 (60 ft./min.). Use of Figure 25 is shown in the

following example.

Example

What is the minimum airﬂow necessary for a LW025A

operating at VI = 75 V, an output current of 3.5 A, and a

maximum ambient temperature of 85 °C?

19.6

(0.77)

TRIM

–

+

OUT

ON/OFF

NC

+

–

IN

LW025A871

DC-DC CONVERTER

MADE IN USA

IN:DC 36-75V, 1.20A

OUT:DC 5.0V, 5.0A

tyco

CASE PIN (OPTIONAL)

26.9

(1.06)

TUV Rheinland

VDE

1414 Tyco Electronics

Data Sheet

March 22, 2000

36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Thermal Considerations (continued)

Heat T ransfer (continued)

Solution

Given: VI = 75 V, IO = 3.5 A, TA = 85 °C

Determine PD (Figure 29): PD = 4.5 W

Determine airﬂow (Figure 25): v = 1.0 ms–1

(200 ft./min.)

8-2477(C)

Note: Conversion factor for linear feet per minute to meters per

second: 200 ft./min. = 1 ms–1.

Figure 24. LW025D, F, G Forced Convection Power

Derating; Either Orientation

8-1985(C)

Note: Conversion factor for linear feet per minute to meters per

second: 200 ft./min. = 1 ms–1.

Figure 25. LW025A Forced Convection Power

Derating; Either Orientation

8-2649(C)

Figure 26. LW025D Power Dissipation vs. Output

Current

8-2645(C)

Figure 27. LW025G Power Dissipation vs. Output

Current

50 60 70 80 90 100

0

4

MAX AMBIENT TEMPERATURE, T

A

(°C)

2

1

3

40 110

MAX CASE

TEMPERATURE

3.0 ms

–1

(600 ft./min.)

5

POWER DISSIPATION, P

D

(W)

2.0 ms

–1

(400 ft./min.)

1.0 ms

–1

(200 ft./min.)

NATURAL

CONVECTION

50 60 70 80 90 100

0

MAX AMBIENT TEMPERATURE, T

A

(°C)

7

3

2

1

4

POWER DISSIPATION, P

D

(W)

9

11040

8

5

6

MAX CASE TEMPERATURE

2.0 ms

–1

(400 ft./min.)

3.0 ms

–1

(600 ft./min.)

1.0 ms

–1

(200 ft./min.)

NATURAL CONVECTION

0.9 1.4 1.9 2.4 2.9

0

OUTPUT CURRENT, I

O

(A)

4

5

6

0.4

1

2

3

POWER DISSIPATION, P

D

(W)

3.4 3.9 4.4 4.9

V

I

= 36 V

V

I

= 48 V

V

I

= 75 V

0.9 1.4 1.9 2.4 2.9

0

OUTPUT CURRENT, I

O

(A)

2

3

6

0.4

1

POWER DISSIPATION, P

D

(W)

3.4 3.9 4.4 4.9

V

I

= 75 V

V

I

= 48 V

V

I

= 36 V

4

5

Tyco Electronics 15 15

Data Sheet

March 22, 2000 36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Thermal Considerations (continued)

Heat T ransfer (continued)

8-2479(C)

Figure 28. LW025F Power Dissipation vs. Output

Current, TA = 25 °C

8-1888(C).a

Figure 29. LW025A Power Dissipation vs. Output

Current, TA = 25 °C

Module Derating

The derating curves in Figures 24—25 were deter-

mined from measurements obtained in an experimental

apparatus shown in Figure 30. Note that the module

and the printed-wiring board (PWB) that it is mounted

on are vertically oriented. The passage has a rectangu-

lar cross-section.

8-1126(C).d

Note: Dimensions are in millimeters and (inches).

Figure 30. Experimental Test Setup

Layout Considerations

Copper paths must not be routed beneath the power

module standoffs.

0.9 1.4 1.9 2.4 2.9 3.4

0

4

OUTPUT CURRENT, I

O

(A)

2

1

3

0.4 4.9

5

3.9 4.4

6

POWER DISSIPATION, P

D

(W)

V

I

= 75 V

V

I

= 48 V

V

I

= 36 V

8

7

5

4

00.5 1 1.5 2 4.5 5

OUTPUT CURRENT, I

O

(A)

POWER DISSIPATION, P

D

(W)

2.5 3 3.5 4

3

2

1

6V

I

= 75 V

V

I

= 48 V

V

I

= 36 V

AIR VELOCITY

AND AMBIENT

TEMPERATURE

MEASURED

BELOW THE

MODULE

AIRFLOW

13 (0.5)

FACING PWB

MODULE

76 (3.0)

PWB

16 Tyco Electronics

Data Sheet

March 22, 2000

36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Outline Diagram

Dimensions are in millimeters and (inches).

Tolerances: x.x ± 0.5 mm (0.02 in.), x.xx ± 0.25 mm (0.010 in.). Pin-to-pin tolerances are not cumulative.

Note: For standard modules, VI(+) is internally connected to the case.

8-1198(C).f

T op View Pin Function

1 Remote

On/Off

2 No Connec-

tion (sync fea-

ture optional)

3V

I(–)

4V

I(+)

5 Case Pin

(pin optional)

6Trim

7 – Output

8 + Output

Side View

Bottom View

50.8

(2.00)

50.8 (2.00)

CASE PIN

(OPTIONAL)

TRIM

–

ON/OFF

NC

–

IN

+

LW025A871

DC-DC CONVERTER

+

MADE IN USA

OUT

IN:DC 36-75V, 1.20A

OUT:DC 5.0V, 5.0A

tyco

9.91 ± 0.38

(0.390 ± 0.015)

0.38 ± 0.13

(0.015 ± 0.005)

STANDOFFS

1.78 x 0.51 THICK

(0.070 x 0.020),

4 PLACES

4.70 (0.185)

MIN

1.02 (0.040) DIA

SOLDER-PLATED BRASS,

ALL PINS

20.3 (0.80)

2.5

(0.10)

4

22.9

(0.90)

5.08 (0.200)

5.08

(0.200)

2.5 (0.10)

REF

10.16 (0.400)

1

2

3

6

7

8

45.72 ± 0.38

(1.800 ± 0.015)

5

5.08

(0.200)

TUV Rheinland

VDE

Tyco Electronics 17

Data Sheet

March 22, 2000 36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Recommended Hole Pattern

Component-side footprint. Dimensions are in millimeters and (inches).

8-1198(C).f

Ordering Information

Table 4. Device Codes

Optional features may be ordered using the device code sufﬁxes shown below. To order more than one option, list

sufﬁxes in numerically descending order. Please contact your Tyco Electronics Account Manager or Applica-

tion Engineer for pricing and availability of options.

Table 5. Option Codes

Input V oltage Output V oltage Output Power Device Code Comcode

48 V 2.0 V 10 W L W025D 108413477

48 V 2.5 V 12.5 W L W025G 108485145

48 V 3.3 V 16.5 W L W025F 108448234

48 V 5 V 25 W L W025A TBD

Option Device Code Sufﬁx

Short pins: 2.79 mm ± 0.25 mm

(0.110 in. ± 0.010 in.) 8

Case ground pin 7

Short pins: 3.68 mm ± 0.25 mm

(0.145 in. ± 0.010 in.) 6

Synchronization 3

Negative logic on/off 1

50.8 (2.00)

CASE OUTLINE

DRILL HOLE OF APPROX.

2.54 (0.100) DIAMETER

TO RECESS STANDOFFS

IF LOWER HEIGHT IS NEEDED

5.08

(0.200)

12.7

(0.50)

2.54 (0.100)

50.8 (2.00)

2.5

(0.10)

10.16

(0.400)

20.32

(0.800)

37.8

(1.49)

3.43

(0.135) 38.86

(1.530)

7.62 (0.300)

12.4

(0.49)

17.78

(0.700)

50.8

(2.00)

45.72 (1.800)

15.24

(0.600)

18 Tyco Electronics

Data Sheet

March 22, 2000

36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Notes

Tyco Electronics 19

Data Sheet

March 22, 2000 36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Notes

Data Sheet

March 22, 2000

36 Vdc to 75 Vdc Inputs; 25 W

LW025 Single-Output-Series Power Modules:

Printed in U.S.A.

March 22, 2000

DS99-393EPS (Replaces DS98-052EPS) Printed On

Recycled Paper

For additional information, contact your Lucent Technologies Account Manager or the following:

POWER SYSTEMS UNIT: Network Products Group, Lucent Technologies Inc., 3000 Skyline Drive, Mesquite, TX 75149, USA

+1-800-526-7819 (Outside U.S.A.: +1-972-284-2626, FAX +1-888-315-5182) (product-related questions or technical assistance)

INTERNET: http://www.lucent.com/networks/power

E-MAIL: techsupport@lucent.com

ASIA PACIFIC: Lucent Technologies Singapore Pte. Ltd., 750D Chai Chee Road #07-06, Chai Chee Industrial Park, Singapore 469004

Tel. (65) 240 8041, FAX (65) 240 8438

CHINA: Lucent Technologies (China) Co. Ltd., SCITECH Place No. 22, Jian Guo Men Wai Avenue, Beijing 100004, PRC

Tel. (86) 10-6522 5566 ext. 4187, FAX (86) 10-6512 3634

JAPAN: Lucent Technologies Japan Ltd., Mori Building No. 21, 4-33, Roppongi 1-Chome, Minato-ku, Tokyo 106-8508, Japan

Tel. (81) 3 5561 5831, FAX (81) 3 5561 1616

LATIN AMERICA: Lucent Technologies Inc., Room 416, 2333 Ponce de Leon Blvd., Coral Gables, FL 33134, USA

Tel. +1-305-569-4722, FAX +1-305-569-3820

EUROPE: Data Requests: DATALINE: Tel. (44) 7000 582 368, FAX (44) 1189 328 148

Technical Inquiries:GERMANY: (49) 89 95086 0 (Munich), UNITED KINGDOM: (44) 1344 865 900 (Ascot),

FRANCE: (33) 1 40 83 68 00 (Paris), SWEDEN: (46) 8 594 607 00 (Stockholm), FINLAND: (358) 9 4354 2800 (Helsinki),

ITALY: (39) 02 6608131 (Milan), SPAIN: (34) 91 807 1441 (Madrid)

Lucent Technologies Inc. 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.