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Product Specification
TXS Series: 75…120 A DC-DC Converters
36 to 75 V DC Input, 1.2, 1.5, 1.8, 2.0 and 2.5 V Output, 90 W to 250 W
REV. FEB 18, 2003
21 of 27
www.power-one.com
Figure 47: TXS100ZB-N with a two stage input
filter according to Figure 32.
Peak measurement in the Vi (-) line.
A two stage input filter can be used, if a better high
frequency damping is required.
Grounded output or grounded case
For safety reasons or to reduce possible EMI
coupling to the secondary, the output circuit may
need to be connected to protective earth.
Grounding the output or the case has a negative
influence on the EMI performance. To overcome
this problem, a two stage input filter is proposed
(see figures 50/51).
Alternatively, if the ground connection is needed
for safety reasons only, an inductor in the ground
line can be used (Figures 48/49). This solution
allows a safe connection and minimises high
frequency emission.
According UL 60950, the ground inductor should
be capable to conduct 1.5 times the value of the
input fuse without failure. The overall impedance of
the connection should be below 0.1
.
One stage input filter and ground Inductor
Vo (+)
Sense (+)
Trim
Sense (-)
Vo (-)
R Load
U o
Vi (+)
Vi (-)
ON/OFF
6
4
7
8
5
2
3
1
Io
U i
C1, C2: 100 uF/100 V
C3, C3: 2.2 nF Y
L1: 1 mH, Ferrite
Ii
+
C3
C4
C2
C1
L1
L2
Figure 48:
TXS100ZB-N with a one stage input
filter according figure 44 and an
inductor in the ground line to the
output.
L2 = 9.6 mH,
I = 50’000, (VAC W620)
Figure 49:
TXS100ZB-N with a one stage input
filter and an earthed output over an
inductor in the ground line according
to Figure 48
Peak measurement in the Vi (-) line.
Two stage input filter and grounded output
Vo (+)
Sense (+)
Trim
Sense (-)
Vo (-)
R Load
U o
Vi (+)
Vi (-)
ON/OFF
6
4
7
8
5
2
3
1
Io
U i
C1, C2: 100 uF/100 V
C3, C3: 2.2 nF Y
L1: 1 mH, Ferrite
L2: 13mH, Amorph
Ii
+
C2
C1
L1
L2
C4
C3
Figure 50:
TXS100ZB-N with a two stage input
filter and ground output.
C1, C2 = 100 uF/100 V (Rubycon YXA), C3, C4 =
2.2 nF/250 V (Wima MP3-Y). L1 = 1 mH; Ferrite
I = 10’000, 16 turns
(B64290L658 T38 Epcos),
L2 = 13 mH, 15 turns, amorphous core (Magnetec
M128-01)
Figure 51:
TXS100ZB-N with a two stage input
filter and an earthed output. Peak
measurement in the Vi (-) line
F