Hardware Reference
In-Depth Information
Figure 9.18
Shaft encoder signal conditioning for low-speed applications
and position sensing
Figure 9.19
Additional logic required to provide direction sensing
connection to a digital input port. Such isolation can be achieved with the aid
of an opto-isolator. These units comprise an optically coupled infra-red emit-
ting LED and photodetector encapsulated in DIL package. The photodetector
may take various forms including a
photodiode, phototransistor
, and
photo-
Darlington
. Typical isolation voltages provided by such devices range from
