Application Note 1427a:
Opto-Isolation Option for ICM-1900/ICM-2900
Overview:
The ICM/AMP 1900 and ICM-2900 modules from Galil have an
option for opto-isolated outputs. This option is specified by including the
name -OPTO when ordering.
ISO OUT POWER (ICM-1900,PIN 19)
OUT POWER (ICM-2900)
OUT[x] (66 - 73)
ICM-1900 / ICM-2900
CONNECTIONS
RP4=10K OHMS
FROM
CONTROLLER
OUT[x] TTL
LOAD (OPTO-MODULE, ETC)
ISO POWER GND (ICM-1900,PIN 35)
OUT GND (ICM-2900)
+5V
The ISO OUT POWER (OUT POWER ON ICM-2900) and ISO
POWER GND (OUT GND ON ICM-2900) signals should be connected to
an isolated power supply. This power supply should be used only to
power the outputs in order to obtain isolation from the controller. The
signal "OUT[x]" is one of the isolated digital outputs where X stands for
the digital output terminals.
The default configuration is for active high outputs. When the
controller is configured in this manner, the opto-isolated outputs will sink
current when the outputs are set low and will not sink current when the
outputs are high. To invert the sense of the outputs, see the discussion
below, "Inverting the Logic Sense of the Opto-Isolation"
NOTE: If power is applied to the outputs with an isolated power
supply but power is not applied to the controller, the outputs will float
high (unable to sink current). This may present a problem when using
active high logic and care should be taken. Using active low logic should
avoid any problems associated with the outputs floating high.
The opto-isolation provides 25ma drive current / output with
approximately 400 usec response time.
