PXI-5421 100 MS/s 16-Bit PXI Arbitrary Waveform Generator
The NI PXI-5421 is a single-channel PXI arbitrary waveform generator designed for automated electronic testing, communications research, component characterization and stimulus-response systems. It combines 16-bit output resolution, sampling rates up to 100 MS/s and 43 MHz analog bandwidth in a compact one-slot PXI module.
The PXI-5421 can generate standard functions, user-defined arbitrary waveforms, linked waveform sequences and scripted output patterns. Available onboard memory configurations range from 8 MB to 512 MB, allowing engineers to generate long, nonrepetitive waveforms and complex test sequences without continuously transferring data from the system controller.
Key Features of the PXI-5421
- Single analog waveform output channel
- 16-bit digital-to-analog converter resolution
- Up to 100 MS/s standard sampling rate
- Up to 105 MS/s in supported clock configurations
- Up to 400 MS/s effective sample rate with interpolation
- 43 MHz analog output bandwidth
- Up to 43 MHz sine-wave generation
- Up to 25 MHz square-wave generation using the low-gain path
- Up to 12.5 MHz square-wave generation using the high-gain path
- Up to 5 MHz triangle and ramp generation
- 12 Vpk-pk maximum output into a 50 Ω load
- Up to 24 Vpk-pk maximum amplitude into an open load
- Software-selectable 50 Ω or 75 Ω output impedance
- 8 MB, 32 MB, 256 MB or 512 MB onboard memory options
- Arbitrary waveform and arbitrary sequence modes
- Waveform linking and programmable looping
- Single, continuous, stepped and burst triggering
- Four external trigger inputs when equipped with the digital connector
- Marker-event output support
- External sample-clock and reference-clock inputs
- PXI_CLK10 and PXI trigger-line support
- NI-TClk multi-module synchronization
- Optional 16-bit LVDS digital pattern output
- Onboard self-calibration
- NI-FGEN software support
PXI-5421 Technical Specifications
| Product Model | PXI-5421 |
|---|---|
| Product Type | PXI arbitrary waveform generator |
| Number of Analog Output Channels | 1 |
| DAC Resolution | 16 bits |
| Maximum Sampling Rate | 100 MS/s nominal; up to 105 MS/s in supported configurations |
| Maximum Effective Sample Rate | 400 MS/s with digital interpolation |
| Analog Bandwidth | 43 MHz |
| Maximum Sine-Wave Frequency | 43 MHz |
| Maximum Square-Wave Frequency | 25 MHz low-gain path; 12.5 MHz high-gain path |
| Maximum Ramp Frequency | 5 MHz |
| Maximum Triangle Frequency | 5 MHz |
| Maximum Output into 50 Ω | 12 Vpk-pk |
| Maximum Output into 1 kΩ | 22.9 Vpk-pk |
| Maximum Output into Open Load | 24 Vpk-pk |
| Minimum Output into 50 Ω | 5.64 mVpk-pk on the low-gain amplifier path |
| DC Offset Range | ±25% of the selected amplitude range |
| Output Impedance | Software-selectable 50 Ω or 75 Ω |
| Output Attenuation | 0 dB to 51 dB |
| Digital Interpolation | 2×, 4× or 8× FIR interpolation |
| Analog Filter | Software-selectable seven-pole elliptical filter |
| Onboard Memory | 8 MB, 32 MB, 256 MB or 512 MB |
| Waveform Generation Modes | Standard function, arbitrary waveform, arbitrary sequence and script |
| Loop Count | 1 to 16,777,215; unlimited for supported burst triggering |
| Start Trigger Modes | Single, continuous, stepped and burst |
| Trigger Edge Detection | Rising edge |
| Minimum Trigger Pulse Width | 25 ns |
| Reference Clock Range | 5 MHz to 20 MHz in 1 MHz increments |
| External Sample Clock Range | Up to 105 MHz, depending on waveform and clock type |
| Internal Clock Accuracy | ±25 ppm |
| Analog Output Connector | SMB jack |
| Clock Input Connector | SMB jack |
| PFI Connectors | 2 × bidirectional SMB jacks |
| Digital Data Connector | Optional 68-pin VHDCI connector |
| Calibration Interval | 2 years |
| Warm-Up Time | 15 minutes |
| Typical Power Consumption | 21.9 W |
| Operating Temperature | 0°C to 55°C in supported chassis |
| Dimensions | 21.6 × 2.0 × 13.0 cm |
| Weight | 345 g |
| Module Format | 3U, one-slot PXI/cPCI module |
| Software Driver | NI-FGEN |
PXI-5421 Part Numbers and Memory Options
| Part Number | Onboard Memory | Digital Output Configuration |
|---|---|---|
| 778697-01 | 8 MB | Without optional LVDS digital pattern output |
| 778697-02 | 32 MB | With LVDS digital pattern output |
| 778697-03 | 256 MB | With LVDS digital pattern output |
| 778697-04 | 512 MB | With LVDS digital pattern output |
The memory configuration affects the maximum waveform length, number of stored waveforms and sequence capacity. Confirm the complete part number, installed memory and presence of the optional digital connector before ordering a PXI-5421.
PXI-5421 Assembly Numbers
| Assembly Number | Configuration |
|---|---|
| 189898-01L | 8 MB PXI-5421 without LVDS output |
| 189898-02L | 32 MB PXI-5421 with LVDS output |
| 189898-03L | 256 MB PXI-5421 with LVDS output |
| 189898-04L | 512 MB PXI-5421 with LVDS output |
16-Bit Arbitrary Waveform Generation
The PXI-5421 uses a 16-bit DAC, providing 65,536 possible digital output codes. This resolution supports precise reconstruction of standard functions and user-created arbitrary waveforms.
Higher vertical resolution is valuable when generating low-level signals, smooth waveforms or stimulus patterns containing small amplitude variations. Final output accuracy also depends on the selected signal path, amplitude range, calibration condition and load impedance.
100 MS/s Sampling Performance
The PXI-5421 supports sampling rates up to 100 MS/s under normal waveform-generation configurations. Its clock architecture also supports rates up to 105 MS/s with applicable clock sources and generation settings.
This sampling performance allows the module to reproduce complex baseband signals, modulated waveforms, pulses and other application-specific stimulus patterns.
400 MS/s Effective Sample Rate
Software-selectable FIR interpolation factors of 2×, 4× and 8× increase the effective sample rate to as much as 400 MS/s. Interpolation inserts calculated samples between the original waveform data points and filters unwanted images from the generated signal.
The 400 MS/s value is an effective interpolated rate. The original user waveform is still generated from the configured waveform-memory sample rate.
43 MHz Analog Bandwidth
The PXI-5421 provides 43 MHz analog bandwidth and can generate sine waves up to 43 MHz. This makes it suitable for communications testing, frequency-response measurements, IF signal generation and general electronic validation.
The direct, low-gain and high-gain output paths have different amplitude and frequency-response characteristics. Select the output path based on the required voltage, waveform type and signal fidelity.
Three Analog Output Paths
Direct Output Path
The direct path provides an amplitude range of approximately 0.707 Vpk-pk to 1 Vpk-pk into 50 Ω. It offers the fastest pulse response and is appropriate when signal fidelity and bandwidth are more important than high output voltage.
Low-Gain Amplifier Path
The low-gain path supports amplitudes from 5.64 mVpk-pk to 2 Vpk-pk into 50 Ω. It can generate square waves up to 25 MHz and provides a broad output range for general-purpose stimulus applications.
High-Gain Amplifier Path
The high-gain path provides up to 12 Vpk-pk into 50 Ω, 22.9 Vpk-pk into 1 kΩ or 24 Vpk-pk into an open load. It supports sine waves up to 43 MHz and square waves up to 12.5 MHz.
Programmable Output Amplitude
The PXI-5421 supports signals ranging from millivolt-level stimulus to 12 Vpk-pk into a terminated 50 Ω load. Software automatically selects the appropriate amplifier and attenuation configuration for the requested amplitude.
Because voltage at the DUT depends on load impedance, always configure the correct load value in NI-FGEN. A high-impedance DUT receives approximately twice the voltage delivered to a matched 50 Ω load.
Programmable DC Offset
The DC offset can be adjusted over a span equal to ±25% of the selected amplitude range. This allows AC waveforms to be positioned around a required bias voltage.
Offset capability is useful for testing unipolar circuits, biased amplifiers, comparators, ADC inputs and other devices that cannot accept a waveform centered at zero volts.
Standard Function Generation
The PXI-5421 generates standard waveforms including sine, square, triangle, ramp-up, ramp-down and DC signals. Standard functions can be configured without first creating and downloading a complete arbitrary waveform record.
The recommended maximum frequency depends on the selected waveform and output path. Sine waves are supported up to 43 MHz, while triangle and ramp signals are recommended up to 5 MHz.
Arbitrary Waveform Mode
Arbitrary waveform mode generates a single user-defined waveform selected from the waveforms stored in onboard memory. The waveform can be generated once, continuously or according to a programmed trigger configuration.
This mode is suitable for customized pulses, transient simulation, sensor emulation, communications signals and other waveform shapes that cannot be created using standard functions.
Arbitrary Sequence Mode
Arbitrary sequence mode allows multiple stored waveforms to be generated in a programmed order. Each segment can identify the required waveform, loop count and marker position.
Sequence generation reduces memory requirements when a long output pattern contains repeated sections. Instead of storing the same waveform data many times, the application can store it once and reference it repeatedly.
Waveform Linking and Looping
The PXI-5421 supports programmable loop counts from one to 16,777,215 for applicable waveform sequences. Supported burst-trigger applications can repeat a waveform without a fixed loop-count limit.
Waveform linking allows engineers to assemble long test patterns from smaller reusable segments, simplifying waveform development and reducing download time.
Deep Onboard Waveform Memory
The PXI-5421 was offered with 8 MB, 32 MB, 256 MB and 512 MB memory configurations. Waveforms and sequence instructions share the onboard Synchronization and Memory Core memory.
| Memory Configuration | Maximum Arbitrary Waveform Samples |
|---|---|
| 8 MB | Approximately 4.19 million samples |
| 32 MB | Approximately 16.78 million samples |
| 256 MB | Approximately 134.22 million samples |
| 512 MB | Approximately 268.44 million samples |
Available sample capacity is slightly different in arbitrary sequence mode because some memory is used for waveform and sequence instructions.
Optional 16-Bit LVDS Digital Pattern Output
Selected PXI-5421 configurations include a 68-pin Digital Data and Control connector. This interface provides a 16-bit LVDS digital pattern output with clock and marker signals.
The analog and digital outputs can be used together to create mixed-signal stimulus for converters, communications hardware, embedded devices and digital control systems.
The 8 MB version is commonly supplied without the optional LVDS connector. Verify the front panel and complete part number when digital pattern output is required.
Triggering and Marker Events
The PXI-5421 supports immediate, software, front-panel and PXI backplane triggering. Generation modes include single, continuous, stepped and burst operation.
Marker events can be placed at defined positions within waveform segments and routed through front-panel PFI connections, the optional digital connector or PXI trigger lines. Markers can coordinate measurements, switching events or external DUT operations with the generated waveform.
External Sample Clock Input
The CLK IN front-panel connector accepts an external sample clock or PLL reference. Supported external sample-clock frequencies extend to 105 MHz, depending on the input waveform type and selected clock destination.
External clocking is useful when waveform generation must follow a DUT clock, system timing source or another synchronized instrument.
PXI_CLK10 and PLL Synchronization
The internal clock can be phase locked to the PXI_CLK10 chassis reference or an external reference connected through CLK IN. Supported PLL reference frequencies range from 5 MHz to 20 MHz in 1 MHz increments.
Using a common reference reduces relative frequency drift between the PXI-5421 and other instruments in a stimulus-response measurement system.
NI-TClk Multi-Module Synchronization
NI-TClk can synchronize multiple compatible SMC-based PXI instruments. This allows engineers to create phase-coherent multichannel waveform-generation systems using several PXI-5421 modules.
NI-TClk can also coordinate the waveform generator with compatible digitizers and digital waveform instruments. Precise performance depends on the chassis, reference clock, sample-clock configuration and applied delay adjustments.
Onboard Self-Calibration
The PXI-5421 includes an onboard 24-bit ADC and precision voltage reference for calibrating DC gain and offset. The software-initiated self-calibration procedure takes approximately 75 seconds.
NI specifies a two-year external-calibration interval and a 15-minute warm-up period. Allow the module to reach a stable temperature before performing accuracy-sensitive tests or self-calibration.
Typical PXI-5421 Applications
- Automated electronic functional testing
- Communications signal generation
- Consumer-electronics validation
- Automotive electronic testing
- Aerospace and defense system testing
- Scientific research
- Component characterization
- Amplifier and filter testing
- Sensor-signal simulation
- Mixed-signal device testing
- ADC and DAC testing
- Long arbitrary waveform generation
- Phase-coherent multichannel stimulus
- Production test equipment
Communications Testing
The combination of 16-bit resolution, 43 MHz bandwidth and deep waveform memory allows the PXI-5421 to generate baseband and intermediate-frequency communications signals.
Engineers can create modulated signals, bursts, multitone waveforms and long nonrepeating patterns for receiver, amplifier, filter and communications-subsystem testing.
Automotive and Aerospace Validation
User-defined waveforms can reproduce sensor outputs, transients and application-specific stimulus patterns used in controller validation. Triggering and marker outputs allow the stimulus to be synchronized with the controller’s operating sequence.
The complete system should include suitable grounding, isolation and external protection when the DUT can expose the generator to high voltage, current or inductive transients.
ADC and Mixed-Signal Testing
The PXI-5421 can provide precise analog stimulus to analog-to-digital converters and mixed-signal devices. Its optional LVDS digital output can provide related digital patterns or control signals.
For converter testing, coordinate the generator with an appropriate digitizer or digital waveform instrument and use a common reference clock to improve timing repeatability.
Stimulus-Response Systems
The PXI-5421 can be paired with a PXI-5122 high-speed digitizer or another compatible PXI measurement module. The generator applies the stimulus while the digitizer captures the DUT response.
PXI backplane timing and NI-TClk synchronization allow these instruments to operate as an integrated automated measurement system.
NI-FGEN Software Support
The PXI-5421 is controlled through the NI-FGEN instrument driver. NI-FGEN provides functions for configuring standard waveforms, downloading arbitrary waveform data, building sequences, configuring scripts and controlling triggers.
The driver supports LabVIEW, LabWindows/CVI and compatible text-based programming environments. TestStand applications can call NI-FGEN-based code as part of automated production and validation sequences.
PXI Chassis Integration
The PXI-5421 occupies one slot in a compatible 3U PXI chassis. Later hardware revisions support PXI hybrid-compatible connections, but chassis and slot compatibility should always be verified before installation.
Ensure adequate chassis airflow because typical power consumption is approximately 21.9 W. Connector clearance should also be checked when using the optional VHDCI digital cable.
PXI-5421 Troubleshooting
The PXI-5421 Is Not Detected
Confirm that the module is fully installed in a compatible PXI slot. Check chassis power, controller communication and NI-FGEN installation, then inspect the device in NI Measurement & Automation Explorer.
No Analog Output Is Generated
Verify that CH 0 is enabled and that waveform generation has been initiated. Check whether the module is waiting for a trigger and confirm the SMB cable and DUT connection.
The Output Amplitude Is Incorrect
Confirm that the configured load impedance matches the actual DUT termination. A high-impedance load receives a different voltage than a matched 50 Ω load.
A Custom Waveform Is Distorted
Check the programmed sample rate, interpolation factor and analog-filter configuration. Confirm that the waveform’s spectral content remains within the 43 MHz analog bandwidth and that the output cable is properly terminated.
A Sequence Stops Unexpectedly
Review the segment instructions, loop counts, waveform allocation and trigger configuration. Confirm that sufficient onboard memory is available for both waveform data and sequence instructions.
The Optional Digital Output Does Not Work
Verify that the installed PXI-5421 version includes the 68-pin VHDCI connector and LVDS output circuitry. Check the digital-data cable, output clock and receiver termination.
External Clock Lock Fails
Confirm that the reference frequency is within the supported range and that the input amplitude, duty cycle and impedance meet the CLK IN requirements. Inspect the SMB cable and reference source.
Multiple Modules Are Not Synchronized
Verify that the modules use a common reference clock and compatible NI-TClk settings. Review the sample rates, trigger routes, interpolation factors and programmed clock-delay adjustments.
Self-Calibration Fails
Allow the module to warm up for at least 15 minutes, disconnect inappropriate external signals and confirm that NI-FGEN can communicate with the device before repeating self-calibration.
PXI-5421 Comparison with Related Waveform Generators
| Model | Primary Configuration | Best Suited For |
|---|---|---|
| PXI-5402 | 14 bit, 100 MS/s, 20 MHz function generator | Standard functions and frequency-list generation |
| PXI-5412 | 14 bit, 100 MS/s arbitrary waveform generator | General-purpose arbitrary waveform generation at lower bandwidth |
| PXI-5421 | 16 bit, 100 MS/s, 43 MHz, up to 512 MB | High-resolution and long arbitrary waveform generation |
| PXI-5441 | High-performance 16-bit PXI arbitrary waveform generator | Advanced communications and signal-generation applications |
| PXIe-5451 | High-speed PXI Express arbitrary waveform generator | Applications requiring higher bandwidth and PXI Express throughput |
PXI-5421 vs PXI-5402
The PXI-5402 is a 14-bit function generator with 20 MHz bandwidth and limited user-defined waveform storage. It is suitable for standard functions, frequency sweeps and relatively simple custom signals.
The PXI-5421 provides 16-bit resolution, 43 MHz bandwidth, deep waveform memory and arbitrary sequence generation. Choose the PXI-5421 when waveform length, signal resolution and sequence flexibility are important.
PXI-5421 vs PXI-5412
The PXI-5412 is a 14-bit, 100 MS/s arbitrary waveform generator with 20 MHz bandwidth. The PXI-5421 increases resolution to 16 bits and provides 43 MHz bandwidth.
Select the PXI-5421 for higher-frequency signals, improved vertical resolution and deeper memory options. The PXI-5412 may be sufficient for lower-bandwidth arbitrary waveform applications.
Selecting the Right PXI-5421 Memory Version
Choose the 8 MB version for shorter waveforms and basic standard-function applications that do not require LVDS digital output. Select the 32 MB version when moderate arbitrary waveform records and the optional digital interface are required.
The 256 MB and 512 MB versions are better suited to long nonrepeating waveforms, complex sequences and applications that store multiple large waveform records in onboard memory.
Recommended Related Products
- PXI-5402 20 MHz Waveform Generator
- PXI-5412 Arbitrary Waveform Generator
- PXI-5441 Arbitrary Waveform Generator
- PXIe-5451 Arbitrary Waveform Generator
- PXI-5122 High-Speed Digitizer
- PXI-4072 Digital Multimeter
- View More NI PXI and PXI Express Modules
Why Choose the PXI-5421?
- Provides high-resolution 16-bit waveform generation
- Supports sampling rates up to 100 MS/s
- Offers 43 MHz analog bandwidth
- Generates up to 12 Vpk-pk into 50 Ω
- Supports standard and arbitrary waveforms
- Provides waveform linking, looping and sequencing
- Offers memory configurations up to 512 MB
- Supports optional 16-bit LVDS digital patterns
- Provides extensive triggering and marker routing
- Supports external clocks and PXI_CLK10
- Supports NI-TClk multi-module synchronization
- Integrates with NI-FGEN and PXI automated test systems
Frequently Asked Questions
What Is the PXI-5421?
The PXI-5421 is a single-channel, 16-bit PXI arbitrary waveform generator with a 100 MS/s sampling rate and 43 MHz analog bandwidth.
What Is the Maximum Output Amplitude?
The PXI-5421 generates up to 12 Vpk-pk into a 50 Ω load, 22.9 Vpk-pk into 1 kΩ or 24 Vpk-pk into an open load.
What Is the Maximum Sine-Wave Frequency?
The maximum recommended sine-wave frequency is 43 MHz.
What Memory Options Are Available?
The PXI-5421 was offered with 8 MB, 32 MB, 256 MB and 512 MB of onboard waveform memory.
Can the PXI-5421 Generate Waveform Sequences?
Yes. It supports arbitrary waveform, arbitrary sequence and script modes with programmable waveform linking, looping, triggering and marker events.
Does the PXI-5421 Have Digital Outputs?
The 32 MB, 256 MB and 512 MB configurations can include an optional 16-bit LVDS digital pattern output through a 68-pin VHDCI connector. Verify the exact module configuration before ordering.
Can Several PXI-5421 Modules Be Synchronized?
Yes. NI-TClk, PXI_CLK10, PXI trigger lines and external clock inputs support synchronized multi-module waveform generation.
Which Software Controls the PXI-5421?
The PXI-5421 is controlled through NI-FGEN and can be integrated with LabVIEW, LabWindows/CVI, TestStand and supported text-based programming environments.
What Is the Calibration Interval?
NI specifies a two-year external-calibration interval and a 15-minute warm-up time for the PXI-5421.
What Are the PXI-5421 Part Numbers?
The main orderable part numbers are 778697-01, 778697-02, 778697-03 and 778697-04, corresponding to different memory and digital-output configurations.
Request a Quote for the PXI-5421
Contact us for current availability, condition, lead time and project pricing for the NI PXI-5421 100 MS/s 16-Bit Arbitrary Waveform Generator. Please provide the required memory size or complete part number so we can identify the correct 8 MB, 32 MB, 256 MB or 512 MB configuration.
