Board Mountable
DC-DC Converters
G Series
Edition 5/5.2000
4/16
Electrical Input Data
General conditions:
–
TA = 25
°C, unless T
C is specified.
– Connector pins i (inhibit) and Vi– interconnected unless
Uinh is specified.
– R input not connected.
Table 2: Input data
Input
BG
CG
Characteristics
Conditions
min
typ
max
min
typ
max
Unit
U
i
Input voltage range
TC min…TC max
14
36
75
V DC
Ui nom Nominal input voltage
Io = 0...Io nom
24
48
U
i uv
Undervoltage lock-out
10
25
P
i 0
No-load input power
U
i nom, Io = 0
2
W
I
i inh
Input current when
U
inh > 2.4 V
16
10
mA
inhibited
U
i min...Ui max
I
inr p
Peak inrush current
U
i nom
1
11
3
A
C
i
Input capacitance
9
2
F
f
s
Switching frequency 2
U
i nom, Io nom
1 Source impedance according to prETS 300132-2 (Ver. 4.3).
2 The switching frequency varies with input voltage and output load (see: Typical performance curves).
Reverse Polarity Protection at Input
The suppressor diode at the input also provides for reverse
polarity protection by conducting current in the reverse di-
rection, thus protecting the unit. An external fuse is required
to limit reverse current:
– for BG units a fast 3 A (F3A) fuse is required.
– for CG units a fast 1.25 A (F1.25A) fuse is required.
Filter recommendations for compliance with
EN 55022, level B
Electromagnetic
emission
requirements
according
to
EN 55022, level B can be achieved by adding an external
filter to the input of the converter. (tbd)
Input Transient Voltage Protection
A suppressor diode at the input together with the input filter
provides an effective protection against input transients
which may be caused for example by short circuits accross
the input lines where the network inductance may generate
high energy pulses.
Table 3: Built-in transient voltage suppressor
Type
Breakdown
Peak power
Peak pulse
voltage (1 mA)
at 1 ms
current
VBR min [V]
PP [W]
IP [A]
BG 1
43
600
8.6
CG 1
90
600
4.1
1 To achieve higher input transient ratings an additional inductor
and capacitor should be provided externally.
Inrush current
The inrush current has been kept as low as possible by
choosing a small internal input capacitance.
Fig. 2
Typical inrush current at Ui nom, Po nom versus time
(BG 3040) measured according prETS 300132-2 (Ver. 4.3).
Steady state
input current
2 A/Div.
50
s/Div.
04007
0