User`s manual

Signal Connections 45

ADLINK Technology Inc. PCI-9524

3.3.5 Interfacing Isolated DI with External Devices

Connecting to a low-side push button

Alternatively, the push button can be connected at the high-side,

i.e. between the ISOVDD and IDn+ pins. Also, the IDIn+ and IDIn-

can be interchanged, since the opto-coupler accepts bipolar input

signals.

Figure 3-17: Connecting to a low-side push button

IDIn+

IDIn-

2.7KO

ISOGND

PCI-9524

5 VDC

ISO5VDD

Push Button