User Manual

GAMMA instabus
Release: February 2012
KNX EIB TP-UART 2-IC
Siemens AG pages 42 Technical Manual
Infrastructure and Cities Sector,
Building Technologies
Control Products and Systems © Siemens AG 2012 page 39
P. O. Box 10 09 53, Subject to change without further notice.
D-93009 Regensburg
7 Appendix
7.1 Typical Application Circuits
In all the applications circuits shown below a default value of VCC=5V is used.
7.1.1 Mode of Operation – Normal
V20
C7
22u/35V
U2
SMAJ43CA
D1
BYG21M
A
B
C3
10u
C4
330u/35V
R1
68/1W
RESn
VCC
GND
TxD
RxD
C5
10n
C6
10n
SAVE
L1
220uH
1 2
TW
C8
220n
C9
220n
1)
NC0
1
R20
2
V20
3
VDDH
4
VSSH
5
SVCC
6
VCC
7
25
X2
24
X1
23
TSTOUT_TW
22 21 20
RxIN
19
VSP
10
11
IND
12
13
VB+
14
VB
15
TxO
16
VDP
34
33
32
31
30
29
28
STxO
8 9
17
18
26 27
35
36
TSTIN_ BDS
TESTMODE
MODE 0
MODE 1
MODE 2
MODE 3
CTM
DIV
V20PD
NC2
NC3
+
+
+
1)
C1
47n/
50V
RxD
VIF
SAVE
RESn
TxD
VB
Y1
4,915MHz
CBYP
47n/
50V
BYP
BDS
1. recommended (close to Pins VDDH and VCC)
Figure 10 Mode of Operation – Normal