PSS, PSK Extended Data Sheet
Positive Switching Regulator (Rugged)
REV. FEB. 25 2004
Page 7 of 18
1.2
1.0
0.8
0.6
0.4
0
0.2
0.4
1.0
1.2
0.2
0.6
0.8
1.4
Vo/Vo nom
Io/Io nom
I o
no
m
Io L
05038
Fig. 4
Overload, short-circuit behaviour Vo versus Io.
Parallel and Series Connection
Outputs of equal nominal voltages can be parallel-con-
nected. Use the current sharing feature (CS) for even distri-
bution of the output current. See also:
Auxiliary Functions.
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!
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.
i Inhibit (Remote On / Off)
Note: With open i input, output is enabled (
Vo = 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. The inhibit characteristics are refer-
enced to the S– remote sense terminal.
Vi+
Gi–
S–
i
S+
Iinh
Vinh
06047
Fig. 6
Definition of Iinh and Vinh
Auxiliary Functions
S
Sense Lines
Note: Sense lines should always be connected! It is rec-
ommended to connect the sense lines directly at the
female connector. See also:
Technical Information.
This feature enables compensation of voltage drop across
the connector contacts and the load lines. In case the sense
lines are connected at the load rather than directly at the
connector, the user must ensure that
Vo max (between Vo+
and Go–) is not exceeded.
Applying generously dimensioned cross-section load leads
avoids troublesome voltage drop. To minimize noise pick-up
wire sense lines in parallel or twisted.
To ensure correct operation, both sense lines must be con-
nected to their respective power output potential. The volt-
age difference between any sense line and its respective
power output pin (as measured on the connector) should
not exceed the values given in the following table.
Table 4: MaximVm allowed voltage compensation
Nominal output
Total voltage difference
Voltage difference
voltage
between both sense lines
between
and their respective output
Go– and S–
12 - 48 V
<1.0 V
<0.25 V
Fig. 5
Sense lines connection
Vi+
i
R
CS
Gi–
Vo+
S+
S–
Go –
Load
06046
Fig. 7
Typical inhibit current Iinh versus inhibit voltage Vinh
4
2
0
–50 –40
20
40
–30
0
–20 –10
10
30
50
5
3
1
I
inh [mA]
V
inh [V]
V
o on
V
o off
V
inh
=
0.8
V
inh
=
2.4
V
06034
0
t
0
Inhibit
1
0.1
1
Vo/Vo nom
tr
tf
06001
Fig. 8
Output response as a function of inhibit signal