NI PCIe-6535 Digital I/O for PCI Express

The NI PCIe-6535 is a high-performance digital I/O interface for PCI Express systems, delivering 32 independently programmable digital channels plus 6 PFI lines. Built for applications requiring high-speed digital signal acquisition and generation—including pattern I/O, change detection, protocol emulation, and semiconductor testing—the device achieves 40 MB/s maximum throughput and operates at sample clock rates from 48 Hz to 10 MHz. Its per-channel directional control and configurable voltage levels (2.5 V and 3.3 V) accommodate diverse logic standards while maintaining 5 V TTL/CMOS compatibility. The device connects via a 68-pin VHDCI connector and is fully compliant with the PCI Express specification.

– Technical Specifications

Digital I/O Architecture
• 32 digital data channels with independent per-channel direction programming
• 6 Programmable Function Interface (PFI) channels
• Maximum clock rate: 5.0 MHz
• Maximum throughput: 40 MB/s
• Continuous data streaming over PCI Express bus

Electrical Characteristics
• Selectable voltage levels: 2.5 V and 3.3 V
• 5 V TTL/CMOS compatible (3.2 V to 3.3 V output)
• Output impedance: 50 Ω
• Input impedance: 50 kΩ
• Input overvoltage protection: −1 V to +6 V
• Output channel maximum: 5 V without damage
• Setup and hold times: 2.0 ns (Rev B devices)

Timing and Synchronization
• Sample clock range: 48 Hz to 10 MHz
• Trigger setup time (tSCTSU): 15 ns nominal
• Trigger delay to edge (tPC): 9 ns nominal
• Trigger to data output delay (tT2D): 65 ns nominal
• Synchronous and asynchronous timing modes
• Synchronization via RTSI, PXI trigger lines, or PFI lines

– Key Features

• Per-channel programmable I/O direction for flexible signal routing
• Change detection and handshaking modes
• 50 Ω impedance matched for signal integrity

– Typical Applications

• Pattern generation and acquisition
• Protocol emulation
• Semiconductor test automation
• Complex digital interfacing

– Compatibility & Integration

Physical
• 68-pin VHDCI connector
• Dimensions: 7.13 in. × 0.85 in. × 4.93 in. (18.1 cm × 2.2 cm × 12.6 cm)
• Weight: 0.24 lb (107.7 g)
• Operating temperature: 0 °C to +45 °C

Software
• NI-DAQmx driver (version 8.8 or newer; 9.6.1 or newer for 6535B/6536B/6537B models)
• LabVIEW, LabWindows/CVI, Microsoft Visual Studio compatible