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GAMMA
instabus
Release: February 2012
KNX EIB TP-UART 2-IC
Technical Manual
pages 42
Siemens AG
Infrastructure and Cities Sector,
Building Technologies
page 14
© Siemens AG 2012
Control Products and Systems
Subject to change without further notice.
P. O. Box 10 09 53,
D-93009 Regensburg
IV
2
0
[
m
A
]
Figure 3 V20 Fallback Characteristic
2.2.10 Pin IND, SMPS-output
The pin IND is the output of the switched mode power supply. Internally the node is clamped to VB-.
The voltages and currents depend on the switched mode power supply concept.
2.2.11 Pin SVCC
This input pin controls the value of VCC. It is possible to switch between 3.3 V and 5 V. If pin SVCC is
connected to VB-, VCC-voltage is 3.3 V. If pin SVCC is connected to VCC, VCC-voltage is 5 V. In any
case it is necessary to connect SVCC to a defined level.
2.2.12 Receive Pin RxIN
The Receive Pin RxIN is coupled to the EIB bus by an external capacitor.
Symbol Parameter
Min
Max
Unit
Note
C
REC
external coupling capacitance
44.5
49.5
nF
typ. 47 nF
1) AC coupled by external capacitor
47 nF
±
5%
Table 13 Receive Pin RxIN