If there are particular areas you need help with, feel free to skip to any of the following sections:

• Introduction
• Why High-Pulsed Current Testing Matters in ATE
• The Reed Relay Advantage
• Key Benefits for ATE Designers
• Applications in Semiconductor Testing
• SHV and MRE Series: Built for High-Power Testing
• Best Practices for High-Current Pulses
• Why Choose Reed Relays Over Alternatives?
• Beyond High-Current Switching: The Full Reed Relay Portfolio
• Why Choose Standex Detect Reed Relays?

Introduction

Automated Test Equipment, ATE, plays a critical role in validating today’s high-performance power semiconductors, including IGBTs, SiC MOSFETs, and Intelligent Power Modules (IPMs). These devices must endure demanding stresses such as high-pulsed currents, elevated voltages, and rapid switching events. To properly assure chip-to-substrate bonding, structural integrity under electrical stress, and reliable field performance, test systems must deliver precise high-current pulses without distortion.

Achieving reliable high-current switching inside ATE platforms is a significant engineering challenge. Test designers require components that can carry 3 to 25 amp pulses, withstand up to 7000 VDC, and operate for hundreds of millions of cycles. Reed relays meet these requirements with a unique combination of clean switching, fast response time, high isolation, and unmatched mechanical endurance, making them a preferred choice in power semiconductor test environments.

This article highlights compact reed relays in the 1-inch class (under 30 mm), ideal for high-channel-density ATE systems. For applications requiring higher voltage or current in larger package sizes, our sales team can support you with additional high-performance options.

Check out the full list
of Standex’s testing
and certifications:

• AEC-Q200
• IEC 60810-4
• IEC 60601-1
• IEC 62109-1/2
• IEC 60664-1
• ISO 6469-3
• IEC 60255-27
• UL Listed
• RohS, REACH

Why High-Pulsed Current Testing Matters in ATE

High-current pulses are essential for evaluating whether a power semiconductor device is robust enough for its intended application. These pulses help validate:

• Proper bonding of chips to substrates
• Electrical and thermal integrity under stress
• Reliability in EV traction inverters, renewable energy converters, BESS modules, and industrial drives

In many ATE platforms, testers must switch repeatedly between static load tests, dynamic pulse tests, and high-voltage isolation tests. The switching device must perform consistently across all these scenarios. With test currents rising due to higher power densities in modern SiC and IGBT devices, ATE designers depend on relays that maintain pulse fidelity, low heat rise, and stable electrical characteristics.

Reed relays deliver consistent results across these high-current test environments and have become a recognized alternative to discontinued mercury-wetted relays, offering similar pulse cleanliness with long lifetime and environmental safety.

The Reed Relay Advantage

Reed relays are hermetically sealed switching elements consisting of ferromagnetic reed contacts inside an evacuated glass capsule. This design provides several inherent advantages:

Standex Detect high-current reed relays extend these advantages into applications requiring 3 to 25 Amp performance, using individual high-current switches (13 A capability) or six reed switches in parallel (up to 25 A).

This combination of high current, high voltage, and long life makes reed relays uniquely suitable for semiconductor ATE systems.

Key Benefits for ATE Designers

Reed relays offer a powerful set of benefits that address the core challenges in high-current ATE switching:

Tackling Core Challenges

Together, these benefits allow ATE designers to build faster, more reliable, and more accurate test systems.

Applications in Semiconductor Testing

Reed relays support a broad range of ATE functions, including:

• IGBT and SiC MOSFET production testing
• IPM module evaluation
• Static and dynamic power device testing
• Pulse integrity verification and surge capability tests
• Chip-to-substrate bonding assessment
• Reliability and stress screening for power semiconductors
• Load-board switching matrices
• Custom high-power test fixtures

These relays are used by leading ATE manufacturers globally in both engineering and mass-production test platforms, helping ensure accurate performance measurements and long-term device reliability.

SHV and MRE Series: Built for High-Power Testing

The Standex SHV and MRE Series are engineered specifically for high-voltage, high-current ATE requirements. Its hermetically sealed reed switch provides:

The reed relay’s low contact resistance and sealed construction ensure that high-current pulses pass through the switch without distortion, enabling accurate device characterization.

The compact SIL package allows ATE designers to maintain channel density while ensuring high isolation and reliable long-term operation.

Best Practices for High-Current Pulses

For optimal performance in high-current test environments:

1. Allow a brief stabilization time
   • Wait at least 5 ms after coil energization before applying the peak current pulse. This ensures the reeds are fully settled.
2. Manage heat properly
   • Ensure appropriate airflow or thermal pathways when operating in the upper current ranges.
3. Use proper socketing or PCB layout
   • Maintain creepage and clearance distances suitable for high voltage applications.
4. Respect pulse duty cycles
   • As with any high-power switching element, ensure thermal limits are not exceeded in continuous rapid-fire test sequences.

Following these guidelines ensures that reed relays deliver maximum lifetime and pulse performance. Figure 1 below illustrates the performance advantage of reed relays in high-current testing. It depicts a perfect square-wave pulse of 5 Amps traveling across the closed reed switch contact surface. Notice how the pulse remains undistorted as it passes completely through the reed relay’s switch, demonstrating the relay’s ability to maintain signal integrity even under demanding conditions.

Why Choose Reed Relays Over Alternatives?

Engineers evaluating switching options for high-current testing often compare:

Beyond High-Current Switching: The Full Reed Relay Portfolio

Standex Detect offers a complete family of reed relays supporting a wide range of ATE requirements:

• SHV Series – High-voltage switching and clean pulse integrity
• KT Series – Compact and reliable for high-density ATE switching matrices
• MRE Series – High-voltage and high-current endurance
• BH Series – High-current reed switch solutions with excellent thermal handling
• Custom High-Current Solutions – Up to 25 A with parallel switch configurations, tailored for IGBT, SiC, and power module testing

This portfolio ensures test engineers can select the ideal relay for their specific current, voltage, isolation, and lifetime requirements.

Why Choose Standex Detect Reed Relays?

Standex Detect combines decades of reed switch engineering expertise with deep application knowledge in high-power ATE systems. Our reed relays deliver:

• Unmatched reliability for high-current semiconductor testing
• Clean, precise pulse switching for device integrity verification
• High-voltage and high-current capability in compact packages
• Hermetically sealed construction for consistent performance
• Custom designs for test currents up to 25 A

With performance validated across leading ATE manufacturers worldwide, Standex Detect reed relays are engineered to meet the rising demands of modern power semiconductor testing.

Ready to Optimize Your ATE System?

Standex Electronics Detect offers a full portfolio of reed relays for test and measurement. Contact us today to discuss your application or request a quote.