PSC Series Extended Data Sheet
Positive Switching Regulators (Rugged)
Input voltage up to 144 VDC
Single output of 12 - 48 VDC
No input to output isolation
•
High efficiency up to 97%
•
Extremely wide input voltage range
•
Very good dynamic properties
•
Input undervoltage lock-out
32
1.3"
88
3.5"
151
5.9"
•
External output voltage adjustment and inhibit
•
Two temperature ranges
•
Continuous no-load and short-circuit proof
•
No derating
Safety according to IEC/EN 60950
Summary
The PSC series of positive switching regulators is designed
as power supply modules for electronic systems. Their ma-
jor advantages include a high level of efficiency that re-
mains virtually constant over the entire input voltage range,
high reliability, low ripple and excellent dynamic response.
Modules with input voltages up to 144 V are specially de-
signed for battery driven mobile applications. The case de-
sign allows operation at nominal load up to 71°C without
additional cooling.
Model Selection and Key Data
Table 1: Type survey
Output
voltage
V
o nom
[V]
12
15
24
36
48
1
2
Output
current
I
o nom
[A]
6
6
6
6
6
Input
voltage range
V
i
[V]
1
18 - 144
22 - 144
31 - 144
44 - 144
58 - 144
Input
voltage
V
i nom
[V]
60
60
60
80
80
Efficiency
2
Type
designation
PSC 126-7iR
PSC 156-7iR
PSC 246-7iR
PSC 366-7iR
PSC 486-7iR
Options
η
min
[%]
88
89
93
95
96
η
typ
[%]
89
90
94
96
97
-9, L, P, C, D
Surges uo to 156 V for 2 s. See also:
Electrical Input Data:
D
V
io min
.
(min. difference
V
i
-
V
o
)
Efficiency at
V
i nom
and
I
o nom
.
Non standard input/output configurations or special custom adaptions are available on request.
Table of Contents
Page
Page
Electromagnetic Compatibility (EMC) ............................. 7
Immunity to Environmental Conditions ........................... 8
Mechanical Data ............................................................. 9
Safety and Installation Instructions .................................. 9
Description of Options ................................................... 11
Accessories ................................................................... 12
EC-Declaration of Conformity ....................................... 13
Summary .......................................................................... 1
Model Selection and Key Data ......................................... 1
Part Number Description ................................................. 2
Functional Description ..................................................... 2
Electrical Input Data ......................................................... 3
Electrical Output Data ...................................................... 4
Auxiliary Functions ........................................................... 6
REV. MAY 12, 2004
Page 1 of 13
PSC Series Extended Data Sheet
Positive Switching Regulators (Rugged)
Part Number Description
PSC 12 6 -7 L i R P C D
Positive switching regulator in case C03 ................... PSC
Nominal output voltage in volt ................................ 12 - 48
Nominal output current in ampere .................................. 6
Operational ambient temperature range
T
A
–25 to 71°C ......................................................... -7
–40 to 71°C (option) ............................................ -9
Input filter (option) ............................................................ L
Inhibit input ....................................................................... i
Control input for output voltage adjustment
1
.................. R
Potentiometer
1
(option) ................................................... P
Thyristor crowbar (option) .............................................. C
Input/output voltage monitor (option) ........................ D/D1
1
Feature R excludes option P and vice versa.
Example:
PSC 126-7LiPC = A positive switching regulator with a 12 V, 6 A output, ambient temperature range of
–25 to 71°C, input filter, inhibit input, output adjust potentiometer and thyristor crowbar.
Functional Description
The switching regulators are designed using the buck con-
verter topology. See also:
Technical Information: Topolo-
gies.
The input is not electrically isolated from the output.
During the on period of the switching transistor, current is
transferred to the output and energy is stored in the output
choke. During the off period, this energy forces the current
to continue flowing through the output, to the load and
back through the freewheeling diode. Regulation is ac-
complished by varying the on to off duty ratio of the power
switch.
I
i
These regulators are ideal for a wide range of
applications, where input to output isolation is not
necessary, or where already provided by an external front
end (e.g. a transformer with rectifier). To optimise
customer’s needs, additional options and accessories are
available.
03018
Vi+
Fuse
1
Input Filter
Option L
Vo+
D (option)
i
Control circuit
Option C
I
o
V
i
V
o
R
G
Gi–
V
t
Option D
V
o
Option P
Go–
Fig. 1
Block diagram
REV. MAY 12, 2004
Page 2 of 13
PSC Series Extended Data Sheet
Positive Switching Regulators (Rugged)
Electrical Input Data
General Conditions:
T
A
= 25°C, unless
T
C
is specified
Table 2a: Input data
Input
Characteristics
Conditions
min
18
PSC 126
typ
max
144
6
12
15
35
250
5
40
250
5
40
350
25
125
A
B
2
A
B
2
35
250
5
40
350
25
125
A
B
2
A
µs
min
22
PSC 156
typ
max
144
7
19
35
mA
A
µs
min
31
PSC 246
typ
max
144
7
Unit
VDC
V
i
Operating input voltage
1
D
V
io min
Min. diff. voltage
V
i
–
V
o
I
o
= 0 -
I
o nom
T
C min
-
T
C max
V
i o
I
i 0
I
inr p
t
inr r
t
inr h
I
inr p
t
inr r
t
inr h
u
i RFI
Undervoltage lock-out
No load input current
Peak value of inrush current
Rise time
Time to half-value
Peak value of inrush current
Rise time
Time to half-value
Input RFI level, EN 55011/22
V
i nom
,
I
o nom
0.15 - 30 MHz
with option L
I
o
= 0,
V
i min
-
V
i max
V
i nom
without option L
V
i nom
with option L
350
25
125
Table 2b: Input data
Input
Characteristics
Conditions
min
44
PSC 366
typ
max
144
8
29
40
40
250
5
40
350
25
125
A
B
2
250
5
40
350
25
125
A
B
2
A
µs
45
mA
A
µs
min
58
PSC 486
typ
max
144
10
Unit
VDC
V
i
V
i o
I
i 0
I
inr p
t
inr r
t
inr h
I
inr p
t
inr r
t
inr h
u
i RFI
1
2
Operating input voltage
1
D
V
io min
Min. diff. voltage
V
i
–
V
o
Undervoltage lock-out
No load input current
I
o
= 0 -
I
o nom
T
C min
-
T
C max
I
o
= 0,
V
i min
-
V
i max
Peak value of inrush current
V
i nom
without option L
Rise time
Time to half-value
Peak value of inrush current
V
i nom
with option L
Rise time
Time to half-value
Input RFI level, EN 55011/22
V
i nom
,
I
o nom
0.15 - 30 MHz
with option L
Surges up to 156 V for 2 s (complying to LES-DB standard for
V
Bat.
= 110 V).
With external input capacitor
C
e
= 470
µF/200
V and option L.
04016
External Input Circuitry
The sum of the lengths of the supply lines to the source or
to the nearest capacitor
≥100 µF
(a + b) should not exceed
5 m unless option L is fitted. This option is recommended in
order to prevent power line oscillations and reduce super-
imposed interference voltages. See also:
Technical Infor-
mation: Application Notes.
+
Vi+
a
b
Gi–
Vo+
Go–
Fig. 2
Switching regulator with long supply lines.
REV. MAY 12, 2004
Page 3 of 13
PSC Series Extended Data Sheet
Positive Switching Regulators (Rugged)
Electrical Output Data
General Conditions:
–
T
A
= 25°C, unless
T
C
is specified
– With R or option P, output voltage
V
o
=
V
o nom
at
I
o nom
Table 3a: Output data
Output
Characteristics
Conditions
min
11.93
0
6.0
30
34
25
30
100
60
±2
±0.02
PSC 126
typ
max
12.07
6.0
7.8
45
49
40
50
min
14.91
0
6.0
50
54
25
30
100
60
±3
±0.02
PSC 156
typ
max
15.09
6.0
7.8
70
74
40
50
min
23.86
0
6.0
50
54
80
60
120
80
±5
±0.02
µs
mV/K
%/K
PSC 246
typ
max
24.14
6.0
7.8
70
75
100
100
mV
mV
pp
Unit
V
A
V
o
I
o
I
oL
u
o
Output voltage
Output current
1
Output current limitation
response
Output
voltage
noise
V
i nom
,
I
o nom
V
i min
-
V
i max
T
C min
-
T
C max
Switching freq.
V
i nom
,
I
o nom
IEC/EN 61204
2
Total
BW = 20 MHz
D
V
o U
D
V
o l
Static line regulation
Static load regulation
Dynamic
load
regulation
Voltage deviat.
V
i min
-
V
i max
,
I
o nom
V
i nom
,
I
o
= 0 -
I
o nom
u
o d
t
d
a
Uo
V
i nom
I
↔
1
/
3
I
o nom
Recovery time
o nom
IEC/EN 61204
2
V
i min
-
V
i max
I
o
= 0 -
I
o nom
Temperature coefficient
D
V
o
/DT
C
(T
C min
-
T
C max
)
Table 3b: Output data
Output
Characteristics
Conditions
min
35.78
0
6.0
50
54
200
120
140
100
±8
±0.02
typ
PSC 366
max
36.22
6.0
7.8
90
94
300
200
min
47.71
0
6.0
55
59
100
180
150
100
±10
±0.02
µs
mV/K
%/K
typ
PSC 486
max
48.29
6.0
7.8
110
115
200
250
mV
mV
pp
Unit
V
A
V
o
I
o
I
oL
u
o
Output voltage
Output current
1
V
i nom
,
I
o nom
V
i min
-
V
i max
T
C min
-
T
C max
Output current limitation
response
Output
voltage
noise
Switching freq.
V
i nom
,
I
o nom
IEC/EN 61204
2
Total
BW = 20 MHz
D
V
o U
D
V
o l
Static line regulation
Static load regulation
Dynamic
load
regulation
Voltage deviat.
V
i min
-
V
i max
,
I
o nom
V
i nom
,
I
o
= 0 -
I
o nom
u
o d
t
d
a
Uo
V
i nom
I
↔
1
/
3
I
o nom
Recovery time
o nom
IEC/EN 61204
2
V
i min
-
V
i max
I
o
= 0 -
I
o nom
Temperature coefficient
D
V
o
/DT
C
(T
C min
-
T
C max
)
1
2
See also:
Thermal Considerations.
See:
Technical Information: Measuring and Testing.
V
o
Vod
05010
D
V
o I
D
V
o I
t
d
I
o
/I
o nom
1
Vod
t
d
t
0
≥10
µs
≥10
µs
t
Fig. 3
Dynamic load regulation.
Page 4 of 13
REV. MAY 12, 2004
PSC Series Extended Data Sheet
Positive Switching Regulators (Rugged)
Thermal Considerations
When a switching regulator is located in free, quasi-station-
ary air (convection cooling) at a temperature
T
A
= 71°C and
is operated at its nominal output current
I
o nom
, the case
temperature
T
C
will be about 95°C after the warm-up
phase, measured at the
Measuring point of case tempera-
ture T
C
(see:
Mechanical Data).
Under practical operating conditions, the ambient tem-
perature
T
A
may exceed 71°C, provided additional meas-
ures (heat sink, fan, etc.) are taken to ensure that the case
temperature
T
C
does not exceed its maximum value of
95°C.
Example: Sufficient forced cooling allows
T
A max
= 85°C. A
simple check of the case temperature
T
C
(T
C
≤
95°C) at full
load
/I
o nom
I
o
ensures correct operation of the system.
Forced cooling
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
05031
Short Circuit Behaviour
A constant current limitation circuit holds the output current
almost constant whenever an overload or a short circuit is
applied to the regulator's output. It acts self-protecting and
recovers – in contrary to the fold back method – automati-
cally after removal of the overload or short circuit condition.
V
o
/V
o nom
1.2
1.0
0.8
0.6
0.4
0.2
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
I
o nom
05033
I
o L
I
o
/I
o nom
Fig. 5
Overload, short-circuit behaviour V
o
versus I
o
.
Convection cooling
T
C max
Auxiliary Functions
i Inhibit
for Remote On and Off
Note:
With open i-input, output is enabled (V
o
= on)
The inhibit input allows the switching regulator output to be
disabled via a control signal. In systems with several units,
this feature can be used, for example, to control the activa-
tion sequence of the regulators by a logic signal (TTL, C-
MOS, etc.). An output voltage overshoot will not occur when
switching on or off.
I
inh
[mA]
06034
T
A min
50
60
70
80
90
100
T
A
[˚C]
Fig. 4
Output current derating versus temperature
Output Protection
A voltage suppressor diode which in worst case conditions
fails into a short circuit (or a thyristor crowbar, option C),
protects the output against an internally generated over-
voltage. Such an overvoltage could occur due to a failure of
either the control circuit or the switching transistor. The out-
put protection is not designed to withstand externally ap-
plied overvoltages. The user should ensure that systems
with Power-One power supplies, in the event of a failure, do
not result in an unsafe condition (fail-safe).
Parallel and Series Connection
Outputs of equal nominal voltages can be parallel-con-
nected. However, the use of a single unit with higher output
power, because of its power dissipation, is always a better
solution.
In parallel-connected operation, one or several outputs may
operate continuously at their current limit knee-point which
will cause an increase of the heat generation. Conse-
quently, the max. ambient temperature value should be re-
duced by 10 K.
Outputs can be series-connected with any other module. In
series-connection the maximum output current is limited by
the lowest current limitation. Electrically separated source
voltages are needed for each module!
REV. MAY 12, 2004
4
3
2
1
V
o
on
V
inh
= 0.8 V
V
inh
= 2.4 V
5
V
o
off
V
inh
[V]
0
–50 –40 –30 –20 –10
0
10
20
30
40
50
Fig. 6
Typical inhibit current I
inh
versus inhibit voltage V
inh
Vi+
Vo+
i
06009
I
inh
V
inh
Gi–
Go–
Fig. 7
Definition of I
inh
and V
inh
Page 5 of 13