Data Sheet
May 1998
CW025 Triple-Output-Series Power Modules:
36 Vdc to 75 Vdc Input; 25 W
The CW025 Triple-Output-Series Power Modules use
adv anced, surface-mount technology and deliver high-quality,
compact, dc-dc conversion at an economical price.
Features
■
Small size: 71.1 mm x 61.0 mm x 12.7 mm
(2.80 in. x 2.40 in. x 0.50 in.)
■
Low output noise
■
Industry-standard pinout
■
Metal case
■
2:1 input voltage range
■
Remote on/off (positive logic)
■
UL
* Recognized,
CSA
†
Certified, and VDE
Licensed
■
Within FCC and CISPR Class A radiated limits
■
Higher accuracy output voltage clamp set point
■
CE mark meets 73/23/EEC and 93/68/EEC
directives
‡
Applications
■
Distributed power architectures
■
Telecommunications
Options
■
Isolated case ground pin
■
Short pins: 2.79 mm
±
0.25 mm
(0.110 in.
±
0.010 in.)
■
Negative logic remote on/off
■
Heat sink available for extended operation
Description
The CW025 Triple-Output-Series P o wer Modules are
dc-dc converters that operate over an input voltage
range of 36 Vdc to 75 Vdc and pro vide three outputs .
These modules offer extremely low noise levels with
industry-standard pinouts in a small footprint. Each
highly reliable and efficient unit features remote
on/off and current limit.
The maximum total output power of the CW025
Triple-Output-Series Power Modules is limited to
25 W. The main output (V
O1
) is designed to deliver
the entire 25 W. The auxiliary outputs (V
O2
and V
O3
)
can provide a total of 22.5 W, as long as the total out-
put power does not exceed 25 W.
Efficiency greater than 80%, a wide operating
temperature range, and a metal case are additional
features of these modules.
*
UL
is a registered trademark of Underwriters Laboratories, Inc.
†
CSA
is a registered trademark of Canadian Standards Associa-
tion.
‡ This product is intended for integration into end-use equipment.
All the required procedures for CE marking of end-use equip-
ment should be followed. (The CE mark is placed on selected
products.)
22 Lucent Technologies Inc.
Data Sheet
May 1998
36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Absolute Maximum Ratings
Stresses in excess of the absolute maximum ratings can cause permanent damage to the device. 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 to all modules over all operating input voltage, resistive load, and
temperature conditions.
* Operation is specified to 75 V, provided the minimum load on Output 1 is at least 0.75 A. Safety agency reports specify 75 V maximum input.
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; however, to achieve maximum safety and system protection, alw ays use an input line fuse. The
safety agencies require a normal-blow, dc fuse with a maximum rating of 5 A in series with the ungrounded input
lead. 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 V
I
— 80 Vdc
I/O Isolation Voltage:
dc
Transient (1 minute) —
——
—500
850 V
V
Operating Case Temperature T
C
–40 100
°
C
Storage Temperature T
stg
–55 125
°
C
Table 1. Input Specifications
Parameter Symbol Min Typ Max Unit
Operating Input Voltage V
I
36 48 72* Vdc
Maximum Input Current
(V
I
= 0 V to 75 V; I
O
= I
O, max
)I
I, max
— — 2.0 A
Inrush Transient i
2
t — — 0.2 A
2
s
Input Reflected-ripple Current, Peak-to-peak
(5 Hz to 20 MHz, 12
µ
H source impedance;
T
C
= 25
°
C; see Figure 18 and Design
Considerations section.)
— — 25 — mAp-p
Input Ripple Rejection (120 Hz) — — 60 — dB
Lucent Technologies Inc. 3
Data Sheet
May 1998 36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Electrical Specifications
(continued)
Table 2. Output Specifications
Parameter Device Symbol Min Typ Max Unit
Output Voltage
(Over all operating input
voltage, resistive load, and
temperature conditions until
end of life. See Figure 20.)
CW025ABK-M
CW025ACL-M
V
O1
V
O2
V
O3
V
O1
V
O2
V
O3
4.80
10.80
–10.80
4.80
13.77
–13.77
—
—
—
—
—
—
5.20
13.70
–13.70
5.20
17.20
–17.20
Vdc
Vdc
Vdc
Vdc
Vdc
Vdc
Output Voltage Set Point
(V
I
= 48 V; T
C
= 25
°
C;
I
O1
= 2.0 A, I
O2
= I
O3
= 0.5 A)
CW025ABK-M
CW025ACL-M
V
O1, set
V
O2, set
V
O3, set
V
O1, set
V
O2, set
V
O3, set
4.90
11.83
–11.83
4.90
14.84
–14.84
5.00
12.20
–12.20
5.00
15.30
–15.30
5.10
12.57
–12.57
5.10
15.76
–15.76
Vdc
Vdc
Vdc
Vdc
Vdc
Vdc
Output Regulation:
Line (V
I
= 36 V to 75 V)
Load (I
O1
= I
O, min
to I
O, max
,
I
O2
=
I
O3
=
I
O, min
)
Temperature (T
C
= –40
°
C to
+100
°
C)
All
All
All
—
V
O1
V
O1
—
—
—
0.1
0.1
0.5
0.2
0.2
1.5
%
%
%
Output Ripple and Noise
(See Figure 19.):
RMS
Peak-to-peak (5 Hz to
20 MHz)
All
All
V
O1
V
O2,
V
O3
V
O1
V
O2,
V
O3
—
—
—
—
—
—
—
—
25
30
100
150
mVrms
mVrms
mVp-p
mVp-p
Output Current
(At I
O
< I
O , min
, the modules ma y
exceed output ripple
specifications.)
CW025ABK-M
CW025ACL-M
I
O1
I
O2,
I
O3
I
O1
I
O2,
I
O3
0.5
0.1
0.5
0.1
—
—
—
—
5.0
1.0
5.0
0.83
A
A
A
A
Output Current-limit Inception
(V
O
= 90% of V
O, nom
and
minimum load on other
outputs.)
CW025ABK-M
CW025ACL-M
I
O1
I
O2,
I
O3
I
O1
I
O2,
I
O3
—
—
—
—
6
2
6
2
7.5
3.0
7.5
3.0
A
A
A
A
Output Short-circuit Current
(V
O
= 1 V and minimum load on
other outputs.)
CW025ABK-M
CW025ACL-M
I
O1
I
O2,
I
O3
I
O1
I
O2,
I
O3
—
—
—
—
8
3
8
3
10.5
4.5
10.5
4.5
A
A
A
A
Efficiency
(V
I
= 48 V; T
C
= 25
°
C; see
Figures 13, 14, and 20.):
I
O1
= 2.5 A, I
O2
= I
O3
= 0.5 A
I
O1
= 2.0 A, I
O2
= I
O3
= 0.5 A CW025ABK-M
CW025ACL-M η
η80
80 82
83 —
—%
%
4 Lucent Technologies Inc.
Data Sheet
May 1998
36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
General Specifications
Dynamic Response
(∆IO/∆t = 1 A/10 µs, VI = 48 V,
TC = 25 °C):
Load Change from IO = 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)
All
All
All
All
VO1
—
VO1
—
—
—
—
—
80
1
80
0.5
—
—
—
—
mV
ms
mV
ms
Table 3. Isolation Specifications
Parameter Min Typ Max Unit
Isolation Capacitance — 0.02 — µF
Isolation Resistance 10 — — MΩ
Parameter Min Typ Max Unit
Calculated MTBF (IO = 80% of IO, max; TC = 40 °C) 2,906,000 hours
Weight — — 113 (4.0) g (oz.)
Table 2. Output Specifications (continued)
Parameter Device Symbol Min Typ Max Unit
Electrical Specifications (continued)
Lucent Technologies Inc. 5
Data Sheet
May 1998 36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-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
(VI = 0 V to 75 V; open collector or equivalent
compatible; signal referenced to VI(–)
terminal. See Figure 21 and Feature
Descriptions.):
CW025XXX-M (positive logic):
Logic Low—Module Off
Logic High—Module On
CW025XXX1-M (negative logic):
Logic Low—Module On
Logic High—Module Off
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)
Turn-on Time
(IO = 80% of IO , max; VO within ±1% of steady
state)
Output Voltage Overshoot
All
All
All
All
All
All
All
Ion/off
Von/off
Von/off
Ion/off
Von/off
—
—
—
0
—
—
—
—
—
—
—
—
—
—
5
0
1.0
1.2
10
50
1.2
—
5
mA
V
V
µA
V
ms
%
Output Overvoltage Clamp CW025ABK-M
CW025ACL-M
VO1
VO2
VO3
VO1
VO2
VO3
—
—
—
—
—
—
6
15
–15
6
19
–19
6.8
17
–17
6.8
21
–21
V
V
V
V
V
V
Output Voltage Set-point Adjustment Range All — 90 — 110 %VO, nom
66 Lucent Technologies Inc.
Data Sheet
May 1998
36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Characteristic Curves
8-1102(C)
Figure 1. CW025 T riple-Output-Series Typical Input
Characteristics
8-1078(C)
Figure 2. CW025 Triple-Output-Series Typical Output
Voltage Variation of 5 V Output Over Ambi-
ent Temperature Range
8-1079(C)
Figure 3. CW025 T riple-Output-Series Typical Out-
put Voltage Variation of 12 V Output Over
Ambient Temperature Range
8-1080(C)
Figure 4. CW025 Triple-Output-Series Typical Output
Voltage Variation of 15 V Output Over
Ambient Temperature Range
01020 80
0.0
1.0
INPUT VOLTAGE, V
I
(V)
INPUT CURRENT, I
I
(A)
30 70
0.1
0.8
0.9
40 50 60
0.2
0.3
0.4
0.5
0.6
0.7
–40 –20 0 20 40 60 80 100
4.95
4.97
4.99
5.01
CASE TEMPERATURE, T (°C)
OUTPUT VOLTAGE, VO1 (V)
5.00
4.98
4.96
–40 –20 0 20 40 60 80 100
11.95
12.10
12.20
12.30
CASE TEMPERATURE, T (°C)
OUTPUT VOLTAGE, V
O
(V)
12.00
12.25
12.15
12.05
–40 –20 0 20 40 60 80 100
15.10
15.20
15.40
15.50
15.60
CASE TEMPERATURE, T (°C)
OUTPUT VOLTAGE, V
O
(V)
15.30
15.55
15.45
15.35
15.25
15.15
Lucent Technologies Inc. 7
Data Sheet
May 1998 36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Characteristic Curves (continued)
8-1103(C)
Figure 5. CW025ABK-M Typical Load Regulation
8-1104(C)
Figure 6. CW025ABK-M Typical Cross Regulation
with Respect to IO1
0.0 0.1 0.2 1.0
11.0
13.5
OUTPUT CURRENT, I
O2
(
A
)
0.3 0.7
12.5
13.0
0.4 0.5 0.6
11.5
12.0
V
I
= 54 V, I
O1
= 0.5 A, I
O3
= 0.1 A
0.8 0.9
V
I
= 54 V, I
O1
= 2.5 A, I
O3
= 0.5 A
OUTPUT VOLTAGE, V
O2
(V)
0 0.5 1.0 4.5
11.0
13.5
OUTPUT CURRENT, I
O1
(A)
1.5 3.5 4.0
12.0
12.5
13.0
11.5
2.0 2.5 3.0
V
I
= 54 V, I
O2
= I
O3
= 0.5 A
V
I
= 54 V, I
O2
= I
O3
= 0.1 A
OUTPUT VOLTAGE, V
O2
(V)
8-1105(C)
Figure 7. CW025ACL-M Typical Load Regulation
8-1106(C)
Figure 8. CW025ACL-M Typical Cross Regulation
with Respect to IO1
0 0.1 0.2 0.8
13.8
16.3
OUTPUT CURRENT, IO2 (A)
0.3 0.7
14.3
14.8
15.3
0.4 0.5 0.6
VI = 54 V, IO1 = 2.5 A, IO3 = 0.45 A
VI = 54 V, IO1 = 0.5 A, IO3 = 0.1 A
15.8
OUTPUT VOLTAGE, VO2 (V)
0.0 0.4 0.9 4.4
13.8
14.8
16.8
OUTPUT CURRENT, I
O1
(A)
1.4 1.9 2.4
15.3
15.8
16.3
14.3
V
I
= 54 V, I
O2
= I
O3
= 0.45 A
2.9 3.4 3.9
V
I
= 54 V, I
O2
= I
O3
= 0.1 A
OUTPUT VOLTAGE, V
O2
(V)
Note: Given the same load conditions, Output 3 has regulation characteristics similar to Output 2, except the
polarity is negative.
88 Lucent Technologies Inc.
Data Sheet
May 1998
36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Characteristic Curves (continued)
8-1107(C)
Figure 9. CW025ABK-M Typical 5 V Output Characteristics
8-1108(C)
Figure 10. CW025ABK-M Typical 12 V Output Characteristics
8-1109(C)
Figure 11. CW025ACL-M Typical 5 V Output Characteristics
0 8
0
5.0
OUTPUT CURRENT, I
O1
(A)
OUTPUT VOLTAGE, V
O1
(V)
2
4.0
4.5
1
3.0
3.5
57
2.5
2.0
0.5
1.5
1.0
34 6
V
I
= 36 V, I
O2
= I
O3
= 0.5 A
V
I
= 54 V
V
I
= 72 V V
I
= 54 V
V
I
= 36 V
9
V
I
= 72 V, I
O2
= I
O3
= 0.1 A
0 4.0
0
14
OUTPUT CURRENT, I
O2
(A)
OUTPUT VOLTAGE, V
O2
(V)
1.00.5
12
2.5 3.5
10
8
2
6
4
1.5 2.0 3.0
V
I
= 36 V, I
O1
= 2.5 A, I
O3
= 0.5 A
V
I
= 54 V
V
I
= 72 V
V
I
= 72 V, I
O1
= 0.5 A, I
O3
= 0.1 A
V
I
= 54 V
V
I
= 36 V
0 8
0
5.0
OUTPUT CURRENT, I
O1
(A)
OUTPUT VOLTAGE, V
O1
(V)
2
4.0
4.5
1
3.0
3.5
57
V
I
= 72 V, I
O2
= I
O3
= 0.45 A
V
I
= 54 V
V
I
= 36 V
2.5
2.0
0.5
1.5
1.0
34 6
V
I
= 72 V,
I
O2
= I
O3
= 0.1 A
V
I
= 54 V
V
I
= 36 V
Data Sheet
May 1998
Lucent Technologies Inc. 9
36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Characteristic Curves (continued)
8-1110(C)
Figure 12. CW025ACL-M Typical 15 V Output Characteristics
0 2.5
3
16
OUTPUT CURRENT, I
O2
(A)
1.0
12
14
0.5
8
10
1.5 2.0
V
I
= 72 V, I
O1
= 2.5 A, I
O3
= 0.45 A
V
I
= 54 V
V
I
= 36 V
6
5
4
OUTPUT VOLTAGE, V
O2
(V)
V
I
= 72 V, I
O1
= 0.5 A, I
O3
= 0.1 A
V
I
= 54 V
V
I
= 36 V
8-1111(C)
Note: Loads varied proportionately from minimum to 50% of full load.
Figure 13. CW025ABK-M Typical Converter
Efficiency
0 20 40 120
55
65
85
PERCENT OF FULL LOAD (%)
EFFICIENCY, η (%)
60 80 100
70
75
80
60
V
I
= 36 V
V
I
= 54 V
V
I
= 72 V
8-1112(C)
Note: Loads varied proportionately from minimum to 50% of full
load.
Figure 14. CW025ACL-M Typical Converter
Efficiency
0 20 40 120
55
65
85
PERCENT OF FULL LOAD (%)
EFFICIENCY, η (%)
60 80 100
70
75
80
60
V
I
= 72 V
V
I
= 36 V
V
I
= 54 V
1010 Lucent Technologies Inc.
Data Sheet
May 1998
36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Characteristic Curves (continued)
8-1098(C)
Figure 15. CW025 Triple-Output-Series Typical
Output Voltage for a Step Load Change
from 75% to 50% of Full Load on
Output 1
8-1099(C)
Figure 16. CW025 Triple-Output-Series Typical
Output Voltage for a Step Load Change
from 25% to 50% of Full Load on
Output 1
8-1100(C)
Figure 17. CW025 Triple-Output-Series Typical
Output Voltage Start-Up when Signal
Applied to Remote On/Off
Test Configurations
8-489(C).a
Note: Input reflected-ripple current is measured with a simulated
source impedance (LTEST) of 12 µH. Capacitor CS offsets pos-
sible battery impedance. Current is measured at the input of
the module.
Figure 18. Input Reflected-Ripple Test Setup
TIME, t (100 µs/div)
OUTPUT VOLTAGE, V
O
(V)
(% OF V
O, set
)
OUTPUT CURRENT, I
O
(A)
(% OF I
O, max
)
75%
50%
25%
99%
100
%
101
%
102
%
TIME, t (100 µs/div)
OUTPUT VOLTAGE, V
O
(V)
(% OF V
O, set
)
OUTPUT CURRENT, I
O
(A)
(% OF I
O, max
)
101%
100%
99%
75%
50%
25%
REMOTE ON/OFF
(2 V/div)
TIME, t (2 ms/div)
OUTPUT VOLTAGE, V
O
(V)
(% OF V
O, set
)
6
4
2
0
0%
50%
100%
TO OSCILLOSCOPE
C
S
220 µF
IMPEDANCE < 0.1 Ω
@ 20 °C, 100 kHz
V
I
(+)
V
I
(–)
L
TEST
BATTERY
12 µH
Lucent Technologies Inc. 11
Data Sheet
May 1998 36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Test Configurations (continued)
8-810(C).c
Note: Use the specified ceramic capacitor. Scope measurement
should be made by using a BNC socket. Position the load
between 50 mm (2 in.) and 75 mm (3 in.) from the module.
Figure 19.Output Noise Measurement Test Setup
8-749(C).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 20. Triple Output Voltage and Efficiency
Measurement Test Setup
Design Considerations
Input Source Impedance
The power module should be connected to a low
ac-impedance input source. Highly inductive source im-
pedances can aff ect the stability of the power module . A
33 µF electrolytic capacitor (ESR < 0.7 Ω at 100 kHz)
mounted close to the power module helps to ensure the
stability of the unit.
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
22.2-950, and EN60950.
For the converter output to be considered meeting the
requirements of saf ety extra-low v oltage (SELV), one of
the following must be true:
■All inputs are SELV and floating, with the output also
floating.
■All inputs are SELV and grounded, with the output
also grounded.
■Any non-SELV input must be provided with reinf orced
insulation from any other hazardous voltages, includ-
ing the ac mains, and must have a SELV reliability
test performed on it in combination with the convert-
ers. Inputs must meet SELV requirements.
If the input meets e xtra-low v oltage (ELV) requirements,
then the converter’s output is considered ELV.
The input to these units is to be provided with a maxi-
mum 5 A normal-blow fuse in the ungrounded lead.
V
O2
(+)
V
O3
(–)
SCOPE
0.47 µF
COPPER STRIP
0.47 µF
R
LOAD3
V
O1
(–)
0.1 µF SCOPE
R
LOAD1
V
O1
(+)
SCOPE
V
O2
, V
O3
,
COM
R
LOAD2
V
I
(+)
I
I
I
O2
SUPPLY
CONTACT
RESISTANCE
CONTACT AND
DISTRIBUTION LOSSES
LOAD3
SENSE
V
O2
(+)
SENSE
V
O3
(–)
V
O2
(+)
V
I
(–) V
O1
(+)
V
O1
(–)
LOAD2
LOAD1
I
O1
SENSE
V
O1
(–)
SENSE
V
O1
(+)
V
O2
, V
O3
COM
SENSE
V
O2,
V
O3
COM
I
O3
V
O3
(+)
η
VOj +() VCOM–[]IOj
j1=
3
∑
VI+() VI–()–()+[]II
--------------------------------------------------------------- 100×=
1212 Lucent Technologies Inc.
Data Sheet
May 1998
36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Feature Descriptions
Output Overvoltage Clamp
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 higher voltage set point
than the primary loop (see Feature Specifications
table). This provides a redundant voltage control that
reduces the risk of output overvoltage.
Current Limit
To provide protection in a fault (output overload) condi-
tion, the unit is equipped with internal current-limiting
circuitry. At the point of current-limit inception, the unit
shifts from voltage control to current control. If the out-
put 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.
Output Voltage Set-Point Adjustment
The output voltage adjustment feature provides the
capability of increasing or decreasing the output volt-
age set point of a module. When the output voltage
adjustment f eature is used, the output v oltage set point
of all three outputs is adjusted.
The output voltage adjustment can be accomplished b y
using an e xternal resistor connected between the TRIM
pin and either the VO1(+) or common pins. With an
external resistor between the TRIM and common pins
(Radj-up), the output voltage set point (VO, adj) increases.
Note: The output voltage adjustment range must not
exceed 110% of the nominal output voltage
between the VO1(+) and common terminals.
With an e xternal resistor connected between the TRIM
and V O1(+) pins (Radj-down), the output voltage set point
(VO, adj) decreases.
Note: The output voltage adjustment must be 90% or
more of the nominal output voltage between the
VO1(+) and common terminals.
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 remote on/off, suffix code “1,”
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
Figure 21). A logic low is Von/off = 0 V to 1.2 V. The max-
imum 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 10 V. The maximum allowable
leakage current of the switch at Von/off = 10 V is 50 µA.
8-758(C).a
Figure 21. Remote On/Off Implementation
CAUTION: To avoid damaging the module or exter-
nal circuitry, the VI(–) pin must be con-
nected to the –48 V source before or
simultaneously to connecting the
ON/OFF pin to the –48 V source (either
directly or through the external on/off
circuitry).
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 option,
the VI(+) is not connected to the case.
Radj-up 42.35
VO, adj VO, nom–
----------------------------------


kΩ
=
Radj-down VO, adj 2.5–()16.94×
VO, nom VO, adj–
-------------------------------------------------


kΩ=
+
–
Von/off
REMOTE
ON/OFF
Ion/off
VI (+)
VI (–)
Data Sheet
May 1998
Lucent Technologies Inc. 13
36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Thermal Considerations
Note: Dimensions are in millimeters and (inches). Drawing is not to scale. 8-866(C).b
Figure 22. Thermal Test Setup
50.8
(2.00)
12.7 (0.50)
101.6
(4.00)
203.2 (8.00)
AIRFLOW
MEASURE CASE
TEMPERATURE AT
THIS POINT
CONNECTORS TO
LOADS, POWER
SUPPLIES, AND
DATALOGGER,
6.35 (0.25) TALL
203.2
(8.00)
9.7 (0.38)
19.1 (0.75)
WIND TUNNEL WALL
AIR VELOCITY PROBE
AMBIENT TEMPERATUR
E
THERMOCOUPLE
AIR-
FLOW
27.9
(1.1)
27.9
(1.1)
dc-dc POWER MODULE
MADE IN USA
12.7 (0.50)
The 25 W triple output power modules are designed to
operate in a variety of thermal environments. As with
any electronic component, sufficient cooling must be
provided to ensure reliable operation. Heat dissipating
components inside the module are thermally coupled
to the case to enable heat removal by conduction, con-
vection, and radiation to the surrounding environment.
The thermal data presented is based on measure-
ments taken in a wind tunnel. The test setup shown in
Figure 22 was used to collect data. Actual performance
can vary depending on the particular application
environment.
1414 Lucent Technologies Inc.
Data Sheet
May 1998
36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Thermal Considerations (continued)
Basic Thermal Performance
The maximum operating temper ature of the CW025 Tri-
ple-Output-Series Power Modules at a given operating
condition can be predicted by combining the power dis-
sipation curv es (Figures 23 through 27), the power der-
ating curve (Figure 28), and the thermal resistance
curve (Figure 29).
Use Figures 23 through 28 and the steps below to pre-
dict the safe operating region for many different operat-
ing and environmental conditions.
1. Calculate the total output power.
POtotal = (IO1 x VO1) + (IO2 x VO2) + (IO3 x VO3)
2. Use POtotal with the appropriate figure (Figure 23
or 24) to determine the fixed losses (PP) associ-
ated with operating at POtotal. These losses are
independent of which output the load is being
drawn from.
3. Use the desired output current (IO1) with
Figure 25 to determine PS1, which is the addi-
tional power being dissipated due to loading of
the main output.
4. Repeat Step 3 for outputs 2 and 3 using the
appropriate figure (Figure 26 or 27) to determine
PS2 and PS3, which is the power dissipated due to
loading of the auxiliary outputs.
5. Find the total power dissipated (PDtotal) by add-
ing the four power dissipations obtained in Steps
2 through 4.
PDtotal = PP + PS1 + PS2 + PS3
6. Use the estimated total power dissipated (PDtotal)
along with Figure 28 to determine the maximum
ambient temperature allowable for a given air
velocity.
For example, consider the CW025ABK-M power
module operating with 54 V input and output currents
IO1 = 2.5 A, IO2 = 0.5 A, IO3 = 0.5 A.
The total output power (POtotal) is 24.5 W. The total
power dissipation is PDtotal = 4.74 W, which is obtained
by adding:
PP= 4.4 W (from Figure 23)
PS1 = 0.22 W (from Figure 25)
PS2 = 0.06 W (from Figure 26)
PS3 = 0.06 W (from Figure 26)
Figure 28 shows that, in natural convection, the maxi-
mum ambient temperature that this module can oper-
ate at is approximately 67 °C.
Keep in mind that the procedure above provides
approximations of the temperature and air velocities
required to keep the case temperature below its maxi-
mum rating. The maximum case temperature, as moni-
tored at the point shown in Figure 22, should be
maintained at 100 °C or less under all conditions.
Air Velocity
The air velocity required to maintain a desired maxi-
mum case temperature for a given power dissipation
and ambient temperature can be calculated using
Figure 28 and the following equation:
where:
■θCA is the thermal resistance from case-to-ambient
air (°C/W).
■TC, max is the desired maximum case temperature
(°C).
■TA is the ambient inlet temperature (°C).
■PDtotal is the total power dissipated by the module
(W) at the desired operating condition.
F or example, to maintain a maximum case temperature
of 85 °C with an ambient inlet temperature of 65 °C and
a power dissipation of 4.74 W, the thermal resistance is:
This corresponds to an airflow greater than 0.36 ms–1
(70 fpm) in Figure 28.
θCA TCmax,TA–
PDtotal
-------------------------------=
θCA ≤ 85 °C65 °C–
4.74
W
------------------------------------- 4.2
°
C/W=
Lucent Technologies Inc. 15
Data Sheet
May 1998 36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Thermal Considerations
(continued)
Air Velocity
(continued)
8-1113(C)
Figure 23. CW025ABK-M Fixed Losses, P
P
8-1114(C)
Figure 24. CW025ACL-M Fixed Losses, P
P
8-1115(C)
Figure 25. CW025ABK-M, CW025ACL-M Losses,
Associated with 5 V Output, P
S1
8-1116(C)
Figure 26. CW025ABK-M, Losses Associated with
±
12 V Output, P
S2
/P
S3
0 5 10 30
1.0
3.5
5.5
OUTPUT POWER, P
O
(W)
POWER DISSIPATION, P
D
(W)
15 20 25
4.0
4.5
5.0
1.5 V
I
= 36 V
V
I
= 72 V
V
I
= 54 V
3.0
2.5
2.0
0 5 10 30
1.0
1.5
2.0
4.0
6.0
OUTPUT POWER, P
O
(W)
POWER DISSIPATION, P
D
(W)
15 20 25
4.5
5.0
5.5
2.5
3.0
3.5
V
I
= 36 V
V
I
= 72 V
V
I
= 54 V
0.0 0.5 1.0 5.0
0.0
0.2
0.4
0.6
1.4
OUTPUT CURRENT, I
O1
(A)
POWER DISSIPATION, P
D
(W)
1.5 2.0 2.5
0.8
1.0
1.2
3.0 3.5 4.0 4.5
V
I
= 36 V
V
I
= 54 V
V
I
= 72 V
0.0 0.1 0.2 1.0
0.00
0.05
0.15
0.20
0.25
0.45
OUTPUT CURRENT, I
O2
OR I
O3
(A)
POWER DISSIPATION, P
D
(W)
0.3 0.4 0.5
0.30
0.35
0.40
0.6 0.7 0.8 0.9
0.10
1616 Lucent Technologies Inc.
Data Sheet
May 1998
36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Thermal Considerations
(continued)
Air Velocity
(continued)
8-1117(C)
Figure 27. CW025ACL-M Losses Associated with
±
15 V Output, P
S2
/P
S3
8-1118(C)
Figure 28. Total Power Dissipation vs. Local
Ambient Temperature and Air Velocity
8-1101(C)
Figure 29. Case-to-Ambient
Thermal Resistance vs.
Air Velocity
Use of Heat Sinks and Cold Plates
The CW025 Triple-Output-Series case includes
through-threaded M3 x 0.5 mounting holes, allowing
attachment of heat sinks or cold plates from either side
of the module. The mounting torque must not exceed
0.56 N/m (5 in.-lb).
The f ollowing thermal model can be used to determine
the required thermal resistance of the sink to provide
the necessary cooling:
where P
D
is the power dissipated by the module,
θ
CS
represents the interfacial contact resistance between
the module and the sink, and
θ
SA
is the sink-to-ambient
thermal impedance (
°
C/W). For thermal greases or
foils, a value of
θ
CS
= 0.1
°
C/W to 0.3
°
C/W is typical.
The required
θ
SA
is calculated from the following equa-
tion:
Note that this equation assumes that all dissipated
power must be shed by the sink. Depending on the
user-defined application environment, a more accur ate
model including heat transf er from the sides and rear of
the module can be used. This equation provides a con-
servative estimate in such instances.
For further information, refer to the
Thermal Energy
Management CC-, CW-, DC-, and DW-Series 25 W
to
30 W
Board-Mounted Power Modules
Technical Note.
0.0 0.1 0.2 1.0
0.00
0.05
0.15
0.20
0.25
0.45
OUTPUT CURRENT, I
O2
OR I
O3
(A)
POWER DISSIPATION, P
D
(W)
0.3 0.4 0.5
0.30
0.35
0.40
0.6 0.7 0.8 0.9
0.10
40 50 60 100
0.0
1.0
2.0
3.0
4.0
8.0
LOCAL AMBIENT TEMPERATURE, T
A
(°C)
TOTAL POWER DISSIPATION, P
D
TOTAL (W)
70 80 90
5.0
6.0
7.0
2.03 ms
–1
(400 ft./min.)
NATURAL CONVECTION
1.02 ms
–1
(200 ft./min.)
0.51 ms
–1
(100 ft./min.)
NAT
CONV 0.25
(50.0) 0.51
(100.0) 2.03
(400.0)
0.0
8.0
VELOCITY, ms
–1
(ft./min.)
0.76
(150.0) 1.78
(350.0)
1.0
6.0
7.0
1.02
(200.0) 1.27
(250.0) 1.52
(300.0)
5.0
4.0
3.0
2.0
THERMAL RESISTANCE (°C/W)
CASE-TO-AMBIENT
PDθCS
T ATc Ts
θSA
•
θSA TCTA–
PDtotal
-------------------- θCS–=
Lucent Technologies Inc. 17
Data Sheet
May 1998 36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Outline Diagram
Dimensions are in millimeters and (inches).
Copper paths must not be routed beneath the power module standoffs.
Tolerances: x.x ± 0.5 mm (0.02 in.), x.xx ± 0.25 mm (0.010 in.).
Note: For standard modules, VI(+) is internally connected to the case and the CASE GROUND pin is not present.
If the CASE GROUND pin is chosen, device code suffix 7, then VI(+) is not connected to the case and the
CASE GROUND pin is floating.
8-1053(C).a
T op View
Side View
Bottom View
12.7 (0.50)
MAX
5.1 (0.020)
0.51
(0.020) 1.02 (0.040) ± 0.08 (0.003) DIA
TIN-PLATED BRASS,
9 PLACES
MIN
4.8 (0.19)
ON/OFF
TRIM
5.1 (0.20)
11.4 (0.45)
3.8 (0.15)
MOUNTING INSERTS
M3 x 0.5,
4 PLACES
10.16 (0.400)
5.08 (0.200)
50.8
(2.00)
20.32
(0.800)
7.1 (0.28)
CASE PIN
OPTIONAL
V
O2
(+)
12.70
(0.500)
7.62
(0.300)
27.94
(1.100)
17.78
(0.700)
25.40
(1.000)
15.24
(0.600)
24.1
(0.95)
61.0
(2.40)
MAX
48.3 (1.90)
71.1 (2.80) MAX
V
O1
(–)
V
O1
(+)
V
O3
(–)
V
O2 &
V
O3
COM
V
I
(–)
V
I
(+)
63.50 ± 0.38 (2.500 ± 0.015)
STANDOFF,
4 PLACES
61.0
(2.40)
MAX
71.1 (2.80) MAX
DC-DC Power Module
Lucent
M3
MADE IN USA
PIN 1
INDICATOR
18 Lucent Technologies Inc.
Data Sheet
May 1998
36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Recommended Hole Pattern
Component-side footprint.
Dimensions are in millimeters and (inches).
Recommended hole size for pin: 1.27 mm (0.050 in.).
8-1053(C).a
11.4 (0.45)
3.8 (0.15)
5.1 (0.20)
CASE OUTLINE
10.16 (0.400)
48.3 (1.90)
71.1 (2.80) MAX
M3 x 0.5 CLEARANCE HOLE
4 PLACES (OPTIONAL)
50.8
(2.00)
12.70
(0.500)
5.08 (0.200)
27.94
(1.100)
17.78
(0.700)
7.62
(0.300)
20.32
(0.800)
25.4
(1.000)
15.24
(0.600)
24.1
(0.95)
61.0
(2.40)
MAX
63.50 ± 0.38 (2.500 ± 0.015)
Lucent Technologies Inc. 19
Data Sheet
May 1998 36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
Ordering Information
Table 4. Ordering Information Table
Optional features may be ordered using the device code suffixes shown below. To order more than one option, list
suffix es in n umerically descending order follow ed by the -M suffix, indicating metric (M3 x 0.5 heat sink hardware).
The heat sinks designed for this package have an M prefix, i.e., MHSTxxx45 and MHSLxxx45 (see
Thermal
Energy Management CC-, CW-, DC-, and DW-Series 25 W to 30 W Board-Mounted Power Modules
Technical
Note).
Table 5. Options Table
Please contact your Lucent Technologies Account Manager or Application Engineer for pricing and availability of
options.
Input
Voltage Output
Voltage Output
Power Remote On/
Off Logic Device
Code Comcode
36 V—75 V +5 V, ±12 V 25 W positive CW025ABK-M 107587206
36 V—75 V +5 V, ±15 V 25 W positiv e CW025A CL-M 107587875
Option Device Code Suffix
Short pins: 2.79 mm ± 0.25 mm
(0.110 in. ± 0.010 in.) 8
Isolated case ground pin 7
Negative remote on/off logic 1
Data Sheet
May 1998
36 Vdc to 75 Vdc Input; 25 W
CW025 Triple-Output-Series Power Modules:
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 +1-972-329-8202) (product-related questions or technical assistance)
INTERNET: http://www.lucent.com
E-MAIL: techsupport@lucent.com
ASIA PACIFIC: Lucent Technologies Singapore Pte. Ltd., 750A Chai Chee Road #05-01, Chai Chee Industrial Park, Singapore 469001
Tel. (65) 240 8041, FAX (65) 240 8053
JAPAN: Lucent Technologies Japan Ltd., 7-18, Higashi-Gotanda 2-chome, Shinagawa-ku, Tokyo 141-0022, Japan
Tel. (81) 3 5421 1600, FAX (81) 3 5421 1700
LATIN AMERICA: Lucent Technologies Inc., Room 9N128, One Alhambra Plaza, Coral Gables, FL 33134, USA
Tel. +1-305-569-4722, FAX +1-305-569-3820
EUROPE: Data Requests: DATALINE: Tel. (44) 1189 324 299, FAX (44) 1189 328 148
Technical Inquiries:GERMANY: (49) 89 95086 0 (Munich), UNITED KINGDOM: (44) 1344 865 900 (Bracknell),
FRANCE: (33) 1 41 45 77 00 (Paris), SWEDEN: (46) 8 600 7070 (Stoc kholm), FINLAND: (358) 9 4354 2800 (Helsinki),
ITALY : (39) 2 6601 1800 (Milan), SPAIN: (34) 1 807 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.
Copyright © 1998 Lucent Technologies Inc.
All Rights Reserved
Printed in U.S.A.
May 1998
DS97-423EPS (Replaces DS94-141EPS) Printed On
Recycled Paper