GS1T70-D540/2
ISDN DC-DC CONVERTER
20 January 1997
1/5
PRELIMINARY DATA
Type
V
i
V
o
I
o
GS1T70-D540/2
28 to 115 V
out 1 : 5V
72 mA
out 2 : 40V
12 mA
FEATURES
Wide operating line termination voltage
Positive or negative input voltage polarity
Input and output filtering
Short-circuit protection on both outputs
Input power during shortcircuit within specifica-
tion
Minimum current drain during stand-by condition:
10
μ
A for Vi<18V
Input-Output2 insulation voltage: 3000V
RMS
for
60 seconds
Output1-Output2 insulation voltage: 3000V
RMS
for 60 seconds
Mechanical dimensions (L x W x H): 50.8 mm x
50.8 mm x 18 mm (2" x 2" x 0.71")
DESCRIPTION
The GS1T70-D540/2 converter has been designed
for the “U” interface of an ISDN-NTBA (Network
Termination Basic Access) system with either 4B3T
or 2B1Q standard trasmission.
Two outputs, 5V/72mA and 40V/12mA are sup-
plied.
The converter offers short-circuit protection (short-
circuit on 40V output doesn’t affect 5V output and
the input power never exceeds the limits of the
specification), input either voltage polarity, 80%
minimum efficiency at maximum load, input and
output filtering to meet very stringent noise require-
ments.
When the input voltage is below 18V, the converter
offers a very high input impedance and a maximum
quiescent current of 10
μ
A according to the standard
ETR 080.
In addition, the wide operating input voltage range
allows it to operate within the whole range of LT
(Line Termination) battery voltage and its relevant
line resistance.
3000V
RMS
isolation voltage for 60 second is pro-
vided between input to output 2 and between output
1 and output 2. No insulation is provided between
input and output 1.
The design of the module has been conducted
using, as reference standards, the following:
EN 60950, VDE0878 part 1 class B (EMC),
EN55022 class B (EMC), CCITT 430, ETS 300 012
and ETS 300 047 (ISDN BASIC ACCESS, Safety
and Protection); anyway, please note that no certi-
fication processes have been carried out on the
module itself.