National Instruments PXI-6527 Digital I/O Module

The NI PXI-6527 (Part Number: 777802-01) is a 48-bit, isolated Digital I/O Module. This module offers 24 solid state relay digital outputs and 24 optically isolated digital inputs. With this model, the user can switch up to 120 mA currents and sense digital levels to 28 VDC. The PXI-6527 operates on Windows 2000/NT/XP and is fully compatible with a broad range of software programs, including LabVIEW, Lab Windows/CVI, and Measurement Studio, etc. This device is a parallel DIO interface and features channel-to-channel isolated I/O’s to reduce noise, protect the user’s system, and break ground loops.

The NI PXI-6527 tends to read the condition of external logic at both TTL levels and non-TTL levels. Each of its 24 input channels has a couple of differential isolated terminals for the signal and its reference. It has an input current of 1.5mA maximum (per channel) at 5 V, and 8 mA max (per channel) at 24 V. A potential difference within 2 VDC to 28 VDC in-between the two terminals of the PXI-6527 registers as a logic high. On the other hand, the module considers a logic low between 0 V and 1 V. The inputs of this module provide 60 VDC isolation from the PC and between channels.