SpikeSafe Source Measure Unit

A Pulsed Source Measure Unit Built For Power and Precision For Unmatched Accuracy and Repeatability

The SpikeSafe SMU is a precision pulsed source measure unit that precisely sources pulsed current and simultaneously digitizes voltage. Optimized for precise and repeatable high-power LED and laser testing, SpikeSafe SMU (Source Measure Unit) current sources deliver precise pulsing with low microsecond rise times, low-jitter triggering and integrated digitizer for more accurate and repeatable high-power LED and laser testing. Pair SpikeSafe Source Measure Unit with Vektrex’s Control Panel software application to quickly and easily sweep and generate IV curves.

The SpikeSafe SMUs feature test-specific current output modes including DC and continuous or single pulse modes. Minimum pulse widths as low as 1us reduce junction temperatures for VCSEL, laser diode and other semiconductor devices. With sustained output power and no duty cycle limitations, SpikeSafe SMUs can power a broad range of applications.

Test What You Couldn’t See

With more and more high-power density LED and laser devices coming to market, there’s a gap between what can tested with traditional source measure units and present engineering and production testing needs. Inadequate power, pulsing and measurement capabilities limit previous generation source measure units.

SpikeSafe® SMU precision pulsed source measure units close that gap by providing accurate pulsing from hundreds of seconds down to 1us with sustained output power. SpikeSafe SMU brings together the speed and power needed for LED and laser testing with integrated high-speed digitizing measurement. Now you can accurately test what you previously couldn’t test, and see what you didn’t have the power to see – with remarkable repeatability.

Introducing “Crazy Stable” Measurements

SpikeSafe SMUs provide the power needed for more accurate, efficient and repeatable measurements.

The SpikeSafe SMU features submicrosecond to low microsecond rise/fall times, programmable load tuning and on-the-fly pulse width correction. Together these mean the device under test experiences less heating and more uniform heating. The result is unmatched measurement stability – measurements described by one beta site evaluator as “crazy stable”.

One and done measurements. No averaging required.
One and done measurements. Production tester upgraded with SpikeSafe SMU improved repeatability 10X, eliminating the need for averaging.

With measurement stability, multiple measurements and averaging is not required speeding test. With measurement stability, false positives and false negatives are eliminated, improving yield and reducing the cost of test.

True Differential Digitizer

General-purpose SMUs typically make single-point voltage measurements, often with loosely specified timing. Digitizing voltmeters make sequential, timed measurements, but each is referenced to a common ground. This ground reference allows noise, such as power line noise, to mix with the desired signal, often completely masking the signal of interest. Vektrex’s SMU uses a balanced True Differential frontend to feed its 500ksps 18bit low-noise ADC. The balanced approach dramatsically reduces common mode noise, allowing the SMU to measure small VF changes such as a 200uV shift in a high voltage LED caused by heating.

The High Power Precision Source Measure Unit

High Current SpikeSafe SMU

SpikeSafe SMUs feature Continuous Power Conversion (CPC). CPC digitally transfers power from available AC or DC sources to the SMU’s pulsing circuity. Since the transfer is continuous, the SMU has no pulse width limitations. The half-width models provide 600W of continuous output power and the full width models can provide up to 6400W. This capability, along with the SMU’s fast pulsing capability, means SpikeSafe Source Measure Unit’s have the flexibility to support DC, continuous pulse and single pulse current testing for the devices of today and tomorrow. 

This high current model is available in 10A, 20A, 40A and 60A

Easily Upgrade Your System with the Force Sense Selector Switch

The SpikeSafe SMU Force Sense Selector Switch supplies integrated Connect/Disconnect and A/B Switch functions. Critical for high speed production environments, the connect/disconnect function is a true isolated switch that will rapidly disconnect power to test devices eliminating control steps and speeding testing. 

A/B Switch functions allow secondary instruments to share load wiring and to be switched in and out. Many test environments include special instrumentation to support very low current measurements and reverse voltage measurements. These measurements, while important, comprise a minimum percentage of total measurements. With so many specialized instruments available and currently in use, the A/B switch function eases usage and simplifies system upgrades where higher currents, faster pulsing and better measurements are important.  

The SpikeSafe SMU with A/B switch is easily integrated into existing system hardware. Minimal software investment is needed to integrate the SpikeSafe SMU allowing preservation of existing software applications and processes.

Learn how to easily upgrade your light measurement system with the force sense selector switch.  

What Current Do You Need?

Easy-to-Use Control Panel Software Application

Control Panel for SpikeSafe Source Measure Unit

Vektrex’s easy-to-use Control Panel Software Application provides turn-key control of the SMU along with external source-measure units, high-speed sampling voltmeters and spectrometers. Control Panel’s intuitive test tools and graphic displays support common optoelectronic tests such as LI sweeps, slope efficiency testing and junction temperature measurement.

Available Python Drivers

The SpikeSafe SMU uses standard SCPI command protocol. Vektrex provides documentation and tools that make it easy to integrate the SMU into test systems. Python drivers for the SpikeSafe products are available here and detailed code samples for critical measurement applications like I-V sweeps, junction temperature measurements, and other measurements are found here.

Resources

Specifications
High Current Specifications
Press Release
Video: How to Generate an IV Curve
Video: How to Achieve “Crazy Stable” Measurements
Video: Easy Light Measurement System Upgrade

Datasheets

500mA Datasheet
4A Datasheet
5A Datasheet
10A Datasheet
20A Datasheet