RabbitCore RCM2200, User Manual

Page: 47 / 60

User’s Manual Sample Circuits D–5
D.4 D/A Converter
The output will initially be 0 V to -10.05 V after the first inverting op-amp, and 0 V to +10.05 V after the sec-
ond inverting op-amp. All lows produce 0 V out, FF produces 10 V out. The output can be scaled by chang-
ing the feedback resistors on the op-amps. For example, changing 5.11 k
Ω
to 2.5 k
Ω
will produce an output
from 0 V to -5 V. Op-amps with a very low input offset voltage are recommended.
Figure D–5:
Sample D/A Converter Connections
+
–
+
– 649 k W
324 k W
162 k W
80.6 k W
40.2 k W
20 k W
10 k W
5.11 k W
CT0–CT7
PA0–PA7
HC374
47 k W
47 k W
CLK
E
+5 V
+5 V
PE2 PE4
1.19 k W
4.99 k W
10 k W
10 k W 5.11 k W
22 pF
22 pF
V
o
V+ > 12 V
V– < –12 V