Output Data Word Format For Em 232 And Em 235; Output Block Diagram For Em 232 And Em 235 - Siemens SIMATIC S7-200 System Manual

S7-200 Specifications

Output Data Word Format for EM 232 and EM 235

Figure A-23 shows where the 12-bit data value is placed within the analog output
word of the CPU.
Figure A-23 Output Data Word Format for EM 232 and EM 235
Note
The 12 bits of the digital-to-analog converter (DAC) readings are left-justified in
the output data word format. The MSB is the sign bit: zero indicates a positive
data word value. The four trailing zeros are truncated before being loaded into
the DAC registers. These bits have no effect on the output signal value.

Output Block Diagram for EM 232 and EM 235

Figure A-24 shows the EM 232 and EM 235 output block diagrams.
11
DATA
Digital-to-analog converter
Figure A-24
A-46
MSB
15 14
AQW XX 0
MSB
15
AQW XX
+
-
Vref
D/A converter
+/- 2V
0
EM 232 and EM 235 Output Block Diagram
4
Data value 11 Bits
Current output data format
4
Data value 12 Bits
Voltage output data format
R
-
+
Voltage-to-current converter
R
M
+
-
R
1/4 R Voltage output buffer
M
S7-200 Programmable Controller System Manual
LSB
3 0
0 0 0 0
LSB
3 0
0 0 0 0
+24 Volt
100
Iout
0..20 mA
Vout
-10.. +10 Volts
A5E00066097-02