PSC Series Extended Data Sheet
Positive Switching Regulators (Rugged)
REV. MAY 12, 2004
Page 2 of 13
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.
Control circuit
Option P
Go–
Vo+
Gi–
Vi+
Input
Filter
Option
L
G
R
i
D (option)
Io
Vo
I i
Vi
Option C
Fuse1
03018
Option D
Vt
Vo
Fig. 1
Block diagram
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.
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.