User`s manual

PCI-FRM01 User’s Manual (Rev 1.1)
-15-
[Description of P1 connector]
PCI-FRM01 Board has six photo-coupler isolated digital outputs and four digital inputs. The equivalent circuit
is as shown figure [4-5].
COM
IN
To FPGA
R
VCC
< Photo coupler input>
OUTP
OUTN From FPGA
R
VCC
<Photo coupler output>
[Figure 4-5. Photo-coupler In/Out Circuit]
The input resistance is 680 ohms thus the flow current is about 5mA when 5V input or about 15mA when 12V
power applied. Maximum operation input voltage is 12V.
The output current is limited by output resistance, the output resistance is 10 ohms.
Continuous output current has to be used under 10mA. The user can change the Input/Output resistance for
special operation.