PXIe-7861 Kintex-7 FPGA Multifunction RIO Module
The PXIe-7861 is a PXI Express multifunction reconfigurable I/O module featuring a user-programmable Kintex-7 160T FPGA. It combines analog acquisition, analog generation, digital I/O and onboard memory for deterministic test, measurement and control systems.
With 16 analog inputs, 8 analog outputs, 32 bidirectional digital I/O lines and 512 MB of onboard DRAM, the PXIe-7861 is designed for hardware-in-the-loop testing, sensor simulation, custom protocol communication and high-speed control applications.
Key Features of the PXIe-7861
- Kintex-7 160T user-programmable FPGA
- 512 MB onboard DRAM
- 16 simultaneously sampled analog input channels
- 16-bit analog input resolution
- 1 MS/s maximum sampling rate per analog input
- 8 analog output channels
- 16-bit analog output resolution
- 1 MS/s maximum analog output update rate
- 32 bidirectional digital I/O lines
- 10 MHz maximum digital clock rate
- 3.3 V single-ended digital logic
- Independent timing and triggering for individual channels
- Support for multirate acquisition
- PXI peer-to-peer data streaming support
PXIe-7861 Technical Specifications
| Product Model | PXIe-7861 |
|---|---|
| Part Number | 786671-01 |
| Product Type | PXI Express Multifunction Reconfigurable I/O Module |
| FPGA | Kintex-7 160T |
| Onboard Memory | 512 MB DRAM |
| Analog Inputs | 16 |
| Analog Input Resolution | 16 bit |
| Maximum Analog Input Rate | 1 MS/s per channel |
| Analog Input Ranges | ±1 V, ±2 V, ±5 V and ±10 V |
| Maximum Differential Inputs | 16 |
| Maximum Single-Ended Inputs | 16 |
| Analog Outputs | 8 |
| Analog Output Resolution | 16 bit |
| Maximum Analog Output Rate | 1 MS/s per channel |
| Analog Output Range | ±10 V |
| Digital I/O | 32 bidirectional lines |
| Maximum Digital Clock Rate | 10 MHz |
| Digital Logic Level | 3.3 V |
| Digital Signaling | Single-ended |
| Bus Type | PXI Express |
| Peer-to-Peer Streaming | Supported |
| Operating Temperature | 0°C to 55°C |
PXIe-7861 Part Number and Accessories
| Item | Part Number | Description |
|---|---|---|
| PXIe-7861 | 786671-01 | Kintex-7 160T multifunction RIO module with 512 MB DRAM |
| SCB-68 HSDIO | 782914-01 | Shielded 68-pin connector block for high-speed digital I/O |
| SCB-68A | 782536-01 | Shielded screw-terminal I/O connector block |
| SHC68-C68-RDIO2 | 156166-02 | 2 m shielded high-speed digital I/O cable |
| SHC68-NT-S | 189041-02 | 2 m shielded cable with unterminated leads |
Accessory requirements depend on the analog and digital connector groups used in the application. Confirm cable, connector block and pinout compatibility before ordering.
Kintex-7 160T FPGA Processing
The PXIe-7861 uses a Kintex-7 160T FPGA to execute custom acquisition, generation, triggering and control logic directly in hardware. This provides deterministic response times without relying on the timing behavior of a host operating system.
Engineers can implement parallel signal processing, custom digital protocols, application-specific triggers and high-speed feedback loops within the FPGA.
512 MB Onboard DRAM
The module includes 512 MB of onboard DRAM for waveform storage, acquisition buffering and FPGA-based block processing. Data can be temporarily stored before transfer to the PXI controller or another supported module.
Onboard memory is particularly useful for long waveform records, high-throughput acquisition and applications in which host transfers cannot occur continuously.
16 Simultaneously Sampled Analog Inputs
The PXIe-7861 provides 16 analog input channels with dedicated 16-bit ADCs. All channels can acquire signals simultaneously at rates up to 1 MS/s per channel, eliminating the channel-to-channel delay associated with multiplexed acquisition hardware.
Independent channel timing and triggering allow users to implement multirate acquisition, individual channel triggers and custom sampling sequences.
Programmable Analog Input Ranges
The analog inputs support programmable ranges of ±1 V, ±2 V, ±5 V and ±10 V. Selecting the smallest suitable voltage range can improve measurement resolution for lower-level signals.
The module supports both differential and single-ended measurements, allowing the input configuration to be selected according to signal grounding and noise requirements.
Eight FPGA-Timed Analog Outputs
Eight 16-bit analog output channels provide update rates up to 1 MS/s per channel over a ±10 V range. The outputs can generate control signals, simulated sensor responses and synchronized test waveforms.
Because the outputs are controlled by FPGA logic, they can respond deterministically to acquired analog signals, digital events or custom trigger conditions.
32 Bidirectional Digital I/O Lines
The PXIe-7861 provides 32 bidirectional digital I/O lines using 3.3 V single-ended signaling. Each line can be configured as an input or output within the FPGA application.
The digital channels support update intervals as short as 100 ns, corresponding to a maximum clock rate of 10 MHz. They can be used for triggering, status monitoring, digital control and custom communication interfaces.
Independent Timing and Triggering
Traditional data acquisition modules often use fixed timing engines shared by multiple channels. The PXIe-7861 allows timing and trigger logic to be implemented directly in the FPGA.
This architecture supports individual channel triggering, multirate sampling, deterministic event sequencing and precise synchronization between analog inputs, analog outputs and digital I/O.
PXI Peer-to-Peer Streaming
The PXIe-7861 supports PXI peer-to-peer streaming, allowing data to be transferred directly to compatible PXI Express modules without routing every transfer through the host processor.
Peer-to-peer streaming can reduce latency and host processing requirements in systems combining FPGA modules, digitizers, signal generators and other high-performance instruments.
Typical Applications
- Hardware-in-the-loop simulation
- Multichannel sensor simulation
- High-speed closed-loop control
- Automotive electronic control unit testing
- Power electronics and inverter testing
- Motor control development
- Custom digital protocol implementation
- FPGA-based signal processing
- Electronic device validation
- Automated production testing
LabVIEW FPGA Programming
The PXIe-7861 can be customized using the LabVIEW FPGA Module and compatible NI-RIO software. Developers can create FPGA applications for custom measurements, signal generation, triggering, communication and control.
After compilation, the FPGA bitfile runs directly on the module, providing deterministic hardware execution and repeatable timing.
Connectivity and Signal Wiring
Compatible shielded cables and SCB-68 series connector blocks provide access to the module’s analog and digital signals. The correct cable should be selected for the multifunction analog connector or high-speed digital connector.
Use appropriate grounding, shielding and cable-routing practices to reduce interference between sensitive analog signals and digital switching lines.
PXI Express System Integration
The PXIe-7861 requires a compatible PXI Express chassis and controller. Chassis selection should consider slot compatibility, cooling capacity, backplane bandwidth and synchronization requirements.
Visit the NI PXI Modules category to explore related PXI hardware for building a complete test system.
Troubleshooting the PXIe-7861
The PXIe-7861 is not detected
Confirm that the module is installed in a compatible PXI Express slot. Check the chassis controller, PXI Platform Services and NI-RIO driver installation.
The FPGA bitfile cannot be loaded
Verify that the FPGA bitfile was compiled specifically for the PXIe-7861. Confirm that the installed LabVIEW FPGA and NI-RIO versions support the module.
Analog measurements contain excessive noise
Check signal grounding, shielding, input configuration and cable routing. Select the smallest suitable voltage range and keep analog wiring away from high-speed digital or power cables.
Digital signals are not recognized correctly
Confirm that the connected device uses compatible 3.3 V logic. Check the FPGA line direction, connector pin assignment and shared digital ground.
Data transfer performance is lower than expected
Review DMA FIFO settings, DRAM buffering, host processing load and PXI Express bandwidth. Peer-to-peer streaming may improve performance when compatible modules are used.
PXIe-7861 Comparison
| Model | FPGA | Analog Inputs | Analog Outputs | Digital I/O | DRAM |
|---|---|---|---|---|---|
| PXIe-7861 | Kintex-7 160T | 16 | 8 | 32 | 512 MB |
| PXIe-7862 | Kintex-7 325T | 16 | 8 | 32 | 512 MB |
| PXIe-7857 | Kintex-7 160T | 8 | 8 | 48 | 512 MB |
| PXIe-7858 | Kintex-7 325T | 8 | 8 | 48 | 512 MB |
Recommended Related Products
- PXIe-7862 – 16-channel multifunction RIO module with a larger Kintex-7 325T FPGA
- PXIe-7857 – Kintex-7 160T module with 8 analog inputs and 48 digital I/O lines
- PXIe-7858 – Kintex-7 325T module with 8 analog inputs and 48 digital I/O lines
- PXIe-7856 – 1 MS/s multifunction RIO module without onboard DRAM
- PXIe-1092 – PXI Express chassis for modular test and measurement systems
Selecting the PXIe-7861
Choose the PXIe-7861 when an application requires 16 simultaneous analog inputs, FPGA-timed analog outputs, digital control lines and onboard DRAM in a single PXI Express module.
If the application requires the same I/O configuration with more FPGA capacity, consider the PXIe-7862. If more digital I/O lines are more important than the number of analog inputs, the PXIe-7857 or PXIe-7858 may be more suitable.
PXIe-7861 vs PXIe-7862
The PXIe-7861 and PXIe-7862 provide the same basic configuration of 16 analog inputs, 8 analog outputs, 32 bidirectional digital I/O lines, 1 MS/s analog operation and 512 MB DRAM.
The primary difference is FPGA capacity. The PXIe-7861 uses a Kintex-7 160T FPGA, while the PXIe-7862 uses a Kintex-7 325T FPGA. The PXIe-7862 is intended for larger FPGA designs and more extensive parallel processing.
Why Choose the PXIe-7861?
- 16 simultaneously sampled analog input channels
- 1 MS/s analog input and output operation
- Eight deterministic analog output channels
- 32 configurable digital I/O lines
- 512 MB DRAM for waveform buffering
- Kintex-7 160T FPGA for custom processing and control
- Peer-to-peer streaming for PXI system integration
Frequently Asked Questions
What is the PXIe-7861 used for?
The PXIe-7861 is used for FPGA-based data acquisition, hardware-in-the-loop testing, sensor simulation, custom protocol communication and deterministic control.
Which FPGA does the PXIe-7861 use?
It uses a user-programmable Kintex-7 160T FPGA.
How many analog channels are available?
The module provides 16 analog input channels and 8 analog output channels, all with 16-bit resolution.
What is the maximum analog sampling rate?
The analog inputs can acquire signals simultaneously at rates up to 1 MS/s per channel. The analog outputs also support update rates up to 1 MS/s.
How much onboard memory does the PXIe-7861 provide?
The module includes 512 MB of onboard DRAM.
How many digital I/O lines are available?
The PXIe-7861 provides 32 bidirectional, 3.3 V digital I/O lines with a maximum clock rate of 10 MHz.
Does the PXIe-7861 support peer-to-peer streaming?
Yes. It supports direct peer-to-peer data streaming to compatible PXI Express modules.
What is the PXIe-7861 part number?
The standard NI part number for the PXIe-7861 is 786671-01.
Request a Quote for the PXIe-7861
Contact us for current availability, lead time and project pricing for the PXIe-7861 Multifunction Reconfigurable I/O Module. We can also help confirm compatible PXI chassis, controllers, cables and terminal accessories for your application.
