Design Guide
Revision 1.12
1998-08-12
HMS F
IELDBUS
S
YSTEMS
AB
Page 33 (35)
Appendix B Hardware Design Examples
B1 Power Supply
B1.1 Dual-Galvanical Isolated Supply for BUS and Electronics.
The dual power supply is based on the DC/DC Brandner DH5W2-41. This circuit has both overload and
over temperature protection. Maximum current for each output is 150 mA.
+24V
24V_Gnd
+5V_BUS
GND_BUS
Vcc
DC
DC
+
+
+
IN
-
-
-
OUT1
OUT2
DH5W2-41
BRANDNER
L1
EMI
1
2
3
D1
SMBJ24A
L2
EMI
1
2
3
C1
10uF
D0
1N5819
1
2
C2
100nF
C3
100uF
+
C4
100nF
C5
100uF
+
Ref.
Component
Note
C1
Capacitor 10u/50V
Electrolyte
C2, C4
Capacitor 100n/63V
Polyester
C3, C5
Capacitor 100u/16V
Electrolyte
D0
Diode 1N5819
D1
Diode SMBJ24A
Transient protection
L1, L2
EMI filter
NFM61R30T472
DC/DC
DC/DC
DH5W2-41
B1.2 Galvanically Isolated Supply for BUS Electronics:
This single power supply is galvanic isolated and built on the DC/DC TRACO TEM2 2411. The circuit has
both overload and over temperature protection. Maximum current is 400mA.
+24V
24V_Gnd
+5V_BUS
GND_BUS
DC
DC
+
+
IN
-
-
OUT
TEM2
2411
TRACO
C1
10uF
D0
1N5819
1
2
L1
EMI
1
2
3
D1
SMBJ24A
C2
100nF
C3
100uF
+