1. Brand Background

SEMIKRON, founded in 1951 and headquartered in Germany, is an established manufacturer in the power semiconductor field. Its high-voltage diode products are known for standard chips combined with modular design, widely used in industrial drives, new energy, and other fields, enjoying a high reputation in the global industrial market. SEMTECH, founded in 1960 and headquartered in the United States, specializes in ultra-high-voltage diode research and development. Its products primarily target applications with extremely high voltage resistance requirements, such as medical imaging and scientific research equipment, boasting deep technical accumulation. HVC, founded in 2008, is a Chinese manufacturer focused on high-voltage components. It adopts a large chip technology route, optimizing chip area and thermal design to create a differentiated advantage in thermal performance, positioning itself as a cost-effective alternative. In terms of delivery time, SEMIKRON's standard lead time is 12 to 20 weeks, with custom products requiring 20 to 24 weeks; SEMTECH's standard lead time is 8 to 16 weeks, with custom products requiring 16 to 20 weeks; HVC's standard lead time is 1 week, with custom products requiring 4 weeks, demonstrating a clear advantage in supply chain responsiveness.

2. Core Technical Specifications Comparison

2.1 Electrical Parameters (SK Series)

In terms of electrical parameters, HVC products maintain equivalent specifications to SEMIKRON's comparable models. Taking SK 6/16 and HVD-SK 6/16 as examples, both have a reverse voltage of 1.6kV, a forward current of 6A, and a surge current of 375A. The key difference lies in the forward voltage drop: SEMIKRON's is 1.3V, while HVC's is 1.2V, a reduction of approximately 8%. This difference stems from HVC's large chip design, where the increased chip area reduces current density, thereby decreasing the forward conduction resistance. For SKa 6/20 and HVD-SKa 6/20, with a reverse voltage of 2.0kV, a forward current of 6A, and a surge current of 375A, the forward voltage drop is reduced from 1.4V to 1.3V, an improvement of approximately 7%. A lower forward voltage drop means reduced conduction loss at the same operating current, which helps lower overall system power consumption and heat dissipation requirements.

2.2 Thermal Performance

Thermal performance is the primary optimization direction for HVC's large chip technology. Under test conditions of 25°C ambient temperature and continuous operation at rated current, the junction temperature of SK 3/16 is 95°C, while HVD-SK 3/16 drops to 75°C, a temperature difference of 20°C; the junction temperature of SK 6/16 is 110°C, while HVD-SK 6/16 drops to 90°C, a temperature difference of 20°C; the junction temperature of SKa 6/20 is 115°C, while HVD-SKa 6/20 drops to 95°C, also a temperature difference of 20°C. This consistent 20°C temperature difference performance results from the comprehensive effects of large chip technology: the chip area increased from approximately 1.0cm² to 1.4cm², a 40% increase, which reduced the current density from 6A/cm² to 4.3A/cm², a 28% reduction; the lower current density directly reduced the Joule heating effect inside the chip, while the larger junction area reduced the bulk resistance, lowering the forward voltage drop from 1.3V to 1.2V, thus reducing conduction loss; the increased chip area also expanded the heat source distribution, and combined with optimized packaging materials, reduced the thermal resistance from 1.8°C/W to 1.5°C/W, an optimization of 17%. According to the junction temperature calculation formula (junction temperature rise equals power loss multiplied by thermal resistance), the superimposed effect of an 8% reduction in power loss and a 17% reduction in thermal resistance ultimately achieved a junction temperature reduction of approximately 20°C. From an engineering application perspective, a lower junction temperature means increased operating margin for the device under the same cooling conditions, or allows for the use of smaller heat sinks to achieve equivalent reliability, providing greater flexibility in system design.

2.3 SEMTECH Series Comparison

For SEMTECH's ultra-high-voltage product line, HVC offers corresponding models covering a voltage rating range of 5kV to 25kV. In core electrical parameters such as reverse voltage and forward current, HVC products match SEMTECH's specifications. Both use the DO-203AB package, with compatible pin layouts, allowing for direct replacement. In terms of reverse leakage current, both are in the same order of magnitude, with differences within measurement error, having limited impact on practical applications.

3. Reliability Test

| Test Item | Test Conditions | SEMIKRON | HVC | Standard Requirements |

Appendix: Complete Model Cross-Reference Table

Below is the complete model cross-reference table for SEMIKRON and SEMTECH high-voltage diodes, sourced from hv-caps.com.

A. Semikron SK/SKa Series - 13 Models

Header Description: Part Number | Repetitive Peak Reverse Voltage(kV) | Average Forward Current(A) | Reverse Recovery Time | Surge Current(A) | HVC Equivalent

B. Semtech SCH Series - 7 Models

Header Description: Part Number | Repetitive Peak Reverse Voltage(kV) | Average Forward Current(A) | Reverse Recovery Time | Surge Current(A) | HVC Equivalent

Note: A total of 20 high-voltage diode models listed above, covering Semikron SK/SKa series and Semtech SCH series. For detailed parameters of specific models or sample requests, please contact sales@hv-caps.com

Conclusion | | :------------------------ | :-------------------------------------------- | :-------------------------------------------------------------------- | :-------------------------------------------------------------------- | :-------------------------------------------------------- | :---------------------------------------------------------------------- | | High Temp Reverse Bias (HTRB) | 125°C, rated reverse voltage, 1000 hours | Reverse leakage current change +25%, Forward voltage drop change +2.5%, Failure rate 0.1% | Reverse leakage current change +20%, Forward voltage drop change +1.7%, Failure rate 0.08% | Leakage current change <50%, Voltage drop change <5%, Failure rate <0.5% | Both meet standard requirements, at the same reliability level | | Power Cycling | ΔTj=80°C, 10-second cycle frequency | 40,000 cycles | 50,000 cycles | 10,000 cycles | Both far exceed standard, HVC slightly better |

Reliability test data indicates that HVC and SEMIKRON both meet industry standard requirements in High Temperature Reverse Bias (HTRB) and power cycling tests, with similar failure rates and cycle life. HVC's slightly longer power cycling life may benefit from lower operating temperatures, which reduce thermal stress fatigue damage to the chip and package interface. However, in practical applications, the lifespan of both can meet the typical 10+ year usage requirements of industrial equipment.

4. Mechanical Compatibility

Identical mechanical dimensions mean that HVC products can be directly installed into existing PCB layouts and heat sink designs without any mechanical modifications, reducing the engineering costs and validation time for replacement.

5. Supply Chain Comparison

HVC's short lead time, low Minimum Order Quantity (MOQ), and free sample policy are particularly suitable for small-batch trial production validation during new product development, as well as urgent replenishment needs for time-sensitive projects.

6. Cost Analysis

This Total Cost of Ownership (TCO) estimate is based on an annual production of 5000 units, with each unit using 2 diodes. It should be noted that this estimate is a theoretical calculation based on ideal optimization conditions. Actual savings depend on factors such as the degree of heat dissipation design optimization in specific applications, inventory management strategies, and equipment operating environment, and may be higher or lower than the stated percentage.

7. Application Scenario Adaptability

Different application scenarios have varying priorities for diode performance and supplier qualifications. Motor drive applications emphasize current capability and thermal performance; SEMIKRON offers mature and reliable solutions, while HVC provides lower temperatures and allows for heat dissipation optimization. Both are viable options, with HVC offering a cost-effectiveness advantage. Industrial power supply applications focus on cost and lead time; SEMIKRON provides stable performance, while HVC is lower cost and offers faster delivery, making it suitable for cost-sensitive projects. Welding equipment applications require high current withstand capability; both technical solutions can meet this. Medical X-ray applications have strict requirements for long-term validation data and traceability; SEMIKRON has extensive data accumulation, while HVC matches performance and has complete documentation. For new designs, HVC can be evaluated; for existing projects, switching requires careful assessment of certification costs. Military and aerospace applications have clear requirements for brand qualifications and certifications; SEMIKRON has comprehensive certifications and high market recognition, while HVC's relevant certifications are still being completed. At this stage, SEMIKRON is prioritized.

8. Comprehensive Evaluation

Scores are for reference only. Actual selection should be combined with the specific project's priorities. For example, military projects might increase the reliability weight to 40%, and medical projects might increase the long-term validation data weight, which would change the scoring results accordingly.

9. Selection Recommendations

Prioritize SEMIKRON for scenarios including: military and aerospace projects with clear brand qualification and certification requirements; existing projects with over 5 years of long-term validation data where switching certification costs are high; and situations where customers specify European or American brands. Consider HVC for scenarios including: new product development stages requiring rapid iteration and sample support; cost-sensitive applications facing Bill of Materials (BOM) optimization pressure; limited heat dissipation space, where the advantage of lower temperature can be utilized to shrink heat sinks or improve ambient temperature adaptability; needing second source certification to diversify single supply chain risk; tight lead times, unable to withstand waits of over 12 weeks; and small to medium batch production requiring flexible Minimum Order Quantity (MOQ) support.

10. Model Cross-Reference Table

SEMIKRON SK/SKa Series

SEMTECH SCH Series

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