New Diodes Offer Better Performance, Efficiency and Insulation

Diodes are not a particularly exciting component, but their utility and ubiquity cannot be overstated, especially in power electronics applications. Diodes are invaluable for protecting sensitive circuitry, guiding current flow, and enabling proper operation in converters.

Major players have brought new diode products to the market in recent weeks.

Nexperia’s 1200 V SiC Schottky diodes. Image used courtesy of Nexperia

Littelfuse 5.0SMDJ-FB Series

The Littelfuse 5.0SMDJ-FB Series offers a surface-mount 5000 W transient voltage suppression diode.

Featuring foldback technology to reduce clamping voltage by up to 15% and designed in the DO-214AB (SMC) package, this series could offer enhanced protection of sensitive DC power lines from transient surges in industrial and ICT systems. The foldback mechanism dynamically lowers the clamping voltage under surge conditions without sacrificing the standoff voltage range, thereby preserving system stability while limiting energy exposure to downstream DC/DC converters. The device also maintains a breakdown voltage that remains consistently higher than the reverse standoff voltage.

The 5.0SMDJ-FB Series diodes. Image used courtesy of Littelfuse

Littelfuse states that the series improves system-level immunity and lifetime by minimizing the voltage protected circuits experience during fast transients, such as EFT and ESD events. The devices are now available in tape and reel format in quantities of 3,000.

Nexperia 1200 V SiC Schottky Diodes

Nexperia’s PSC20120J and PSC20120L are 1200 V, 20 A silicon carbide Schottky diodes engineered for high-efficiency power conversion in industrial, telecom, and data center environments. Built on a merged PiN Schottky architecture, these diodes exhibit zero reverse recovery and temperature-independent switching and maintain a low capacitive charge of 85 nC at 800 V reverse bias and 20 A forward current.

Maximum power dissipation values as a function of temperature. Image used courtesy of Nexperia

These devices’ forward voltage is tightly controlled, with 1.5-1.8 V at 25 °C and 2.2-2.6 V at 150 °C for a 20 A load. The diodes also sustain repetitive reverse voltages up to 1200 V and surge currents up to 710 A (10 µs pulse), supported by IFSM ratings of 135 A (10 ms) at 25 °C. Reverse leakage current remains under 500 µA at 150 °C.

Notably, the PSC20120J features a surface-mount D2PAK (TO-263-2) Real-2-Pin package, while the PSC20120L is housed in a TO-247-2 through-hole format, but both are thermally optimized for continuous operation up to 175°C. Thermally, the devices support power densities up to 200 W (D2PAK) and 190 W (TO-247), with junction-to-case thermal resistance as low as 0.6 K/W.

Vishay VS-3C Series SiC Schottky Diodes

Vishay has introduced three new Gen 3 650 V and 1200 V SiC Schottky diodes, which are engineered for fast-switching, high-efficiency power conversion.

Diode dimensions. Image used courtesy of Vishay

Supporting 1A and 2A of forward current, the devices incorporate a merged PiN Schottky structure to achieve reduced forward voltage (as low as 1.30 V) and improved surge current handling. To improve temperature invariant switching and minimize reverse recovery losses, these devices offer a capacitive charge as low as 7.2 nC. These features collectively position the diodes for hard-switching topologies and high-frequency DC/DC or AC/DC converters.

From a packaging perspective, the devices are encapsulated in the ultra-thin 0.95 mm SlimSMA HV (DO-221AC) package and provide up to 3.2 mm creepage distance. The SlimSMA HV package also features a high CTI (≥600) for improved insulation resistance.

New Offerings for Power Engineers

All power engineers will undoubtedly come across diodes in their designs. With these new products at their disposal, designers can strive for systems that offer higher safety, reliability, and performance.