PSC126-7LIRPCD Power-One, PSC126-7LIRPCD Datasheet - Page 11

• Manufacturer Part Number: PSC126-7LIRPCD
• Description: Psc Series Extended Positive Switching Regulators Rugged
• Manufacturer: Power-One

Table 10: Crowbar trigger levels
REV. MAY 12, 2004
Description of Options
-9 Extended Temperature Range
The operational ambient temperature range is extended to
T
P Potentiometer
Option P excludes R function. The output voltage V
adjusted with a screwdriver in the range from 0.92 - 1.08 of
the nominal output voltage V
However, the minimum differential voltage D V
input and output voltages as specified in: Electrical Input
Data should be maintained.
L Input Filter
Option L is recommended to reduce superimposed inter-
ference voltages and to prevent oscillations, if input lines
exceed approx. 5 m in total length. The fundamental wave
(approx. 120 kHz) of the reduced interference voltage be-
tween Vi+ and Gi– has, with an input line inductance of
5 µH, a maximum magnitude of 4 mV AC.
The input impedance of the switching regulator at 120 kHz
is about 3.5 Ω. The harmonics are small in comparison with
the fundamental wave. See also: Electrical Input Data: RFI .
With option L, the maximum permissible additionally su-
perimposed ripple u
a specified input frequency f
u
C Crowbar
This option is recommended to protect the load against
power supply malfunction, but it is not designed to sink ex-
ternal currents.
A fixed-value monitoring circuit checks the output voltage
V
crowbar triggers and disables the output. It may be deacti-
vated by removal of the input voltage. In case of a switching
transistor defect, an internal fuse prevents excessive cur-
rent.
V
t
i max
Characteristics
A
Note: As a central overvoltage protection device, the
crowbar is usually connected to the external load via
distributed inductance of the lines. For this reason, the
overvoltage at the load can temporarily exceed the trig-
ger voltage V
decentralized overvoltage protection elements may
have to be used additionally. For further information see:
Technical Information: Application Notes.
o
s
o c
. When the trigger voltage V
= –40 to 71°C. ( T
= 10 V
Trigger voltage
Delay time
pp
at 100 Hz or V
o c
. Depending on the application, further
i
C
of the input voltage (rectifier mode) at
= –40 to 95°C, T
Conditions
V
I
T
o
C min
i min
= 0 - I
- V
- T
pp
o nom
i
o nom
has the following values:
i max
C max
= 1000 Hz/ f
o c
.
is reached, the thyristor
13.5
min
S
= –55 to 100°C.)
12 V
i
• 1V
max
i o min
1.5
16
between
o
can be
16.5
min
Page 11 of 13
15 V
Positive Switching Regulators (Rugged)
max
1.5
19
D Save Data Input Undervoltage Monitor
Terminal D and Go– are connected to a normally conduct-
ing field effect transistor (JFET). The switching characteris-
tics of the option D output are shown in fig. Definition of V
and V
overvoltages.
The voltage V
tiometer by means of a screwdriver. The hysteresis V
is <2%. Terminal D stays low for a minimum time t
order to prevent any oscillation. V
between V
comes conductive when V
V
Fig. 13
Test circuit with definition of voltage V
Fig. 14
Definition of V
Note: Output instead of input undervoltage monitor is
available on request (Option D1).
t
V
V
D high
D low
Gi –
H
Vi +
min
27
. A 0.5 W Zener diode provides protection against
V
PSC Series Extended Data Sheet
D
24 V
i min
max
1.5
31
JFET
t
t
can be externally adjusted with a trim poten-
and V
and V
min
H
40
i max
V
36 V
t
V
. Please note that the JFET be-
D
H
45.5
8.2 V
max
1.5
Go –
increases above 7 V approx.
D
t
V
can be set to a value
min
I
55
D
D
D
48 V
and current I
max
1.5
60
10 kΩ
100 pF
low min
Unit
11025
µs
H
V
11026
D
V
+5 V
of V
i
, in
t
t