Register Structure & Connection
••
17
3.5 Isolated Digital Output Channels
The connection of isolated-digital output is shown as following
diagram. When the isolated digital output goes “ON”, the sink
current will be conducted through the transistors. When the
isolated digital output goes “OFF”, no current could flow through
the transistor. Please note that when the loading is as
“inductance type loading” such as relay, coil or motor, the VDD
signal must be connect to the external power source. The extra
connection is to utilize the ‘fly-wheel diode’ to form a current-
release closed loop, so that the transistor won’t be destroyed by
the reverse high voltage which conduct by the inductance
loading.
DD
V
Load
5~35V
-
IGND
VDD n
+
V5V
DC-DC
Convertor