User Manual

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
IV20 [mA]
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