DS26502 T1/E1/J1/64KCC BITS Element
13.8 Recommended Circuits
Figure 13-4. Software-Selected Termination, Metallic Protection
Table 13-1. Component List (Software-Selected Termination, Metallic
Protection)
NAME
F1 and F2
S1 and S2
S3 andS4
T1 and T2
T3 and T4
Note 1:
Note 2:
Note 3:
Note 4:
DESCRIPTION
1.25A slow blow fuse
25V (max) transient suppressor
77V (max) transient suppressor
Transformer 1:1CT and 1:136CT (5.0V, SMT) (Note 1)
Transformer 1:1CT and 1:2CT (3.3V, SMT) (Note 1)
Dual common-mode choke (SMT)
T3 and T4 are optional. For more information, contact the Telecom Support Group at
telecom.support@dalsemi.com.
The layout from the transformers to the network interface is critical. Traces should be at least 25
mils wide and separated from other circuit lines by at least 150 mils. The area under this portion
of the circuit should not contain power planes.
Some T1 (never in E1) applications source or sink power from the network-side center taps of
the Rx/Tx transformers.
A list of transformer part numbers and manufacturers is available by contacting
telecom.support@dalsemi.com.
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