National Instruments 777810-01 Isolated Digital I/O

Popularly known as the PCI-6527, the 777810-01 is a 48-bit, parallel, isolated digital I/O interface made specifically for PXI or CompactPCI chassis and PCI bus computers. 24 optocoupler inputs and 24 solid-state relay outputs make up the 48 isolated digital data acquisition channels on this device. It's perfect for low-voltage isolation and switching applications in industrial and laboratory settings because it can sense digital levels up to 28 VDC and switch currents up to 120 mA.

Because it is entirely software configurable and jumperless, this device ensures user-friendliness and does not require manual setting after power-up. The National Instruments PCI MITE interface is incorporated into the 777810-01, improving its dependability and performance. Input line glitches can be removed with digital filtering, and all input lines have the ability to produce interrupts on rising or falling edges to alert you to changing data.

With its optically-isolated digital input lines, the 777810-01 is suitable for checking the status of external digital logic at both TTL and non-TTL levels. Its solid-state relay outputs have the ability to regulate digital logic levels at both TTL and non-TTL levels, as well as to switch external devices that need high input currents. This device's isolation from the computer guarantees that noise and harsh ground are successfully separated from external signals, and vice versa.

Software options for programming this device include LabVIEW, LabWindows/CVI, Visual C++, and Visual Basic. These options can all be used with the NI-DAQ driver software that comes with the device. NI-DAQ offers a vast function library that lets you take full advantage of its capabilities.

The device has a 100-pin I/O connector that can be shielded with a SH100100-F cable to connect to 100-pin accessories or 50-pin accessories with a R1005050 cable. An LED, a current-limiting resistor, digital filtering, and change-detection circuitry are all included in the optically isolated inputs. Each channel has its own positive and negative terminals and can accept a maximum input voltage of +28 VDC.

The output channels have protection circuitry to guard against damage from excessive current. They use solid-state relays with LH1546 components. The relay raises its resistance when the current goes above the designated range and then resumes normal operation when the current falls back within the defined range.