Littelfuse's new SIDACtor protection thyristors provide 45% lower junction capacitance than clamp devices

PESD1CAN electrostatic protection SOT23-3 24V two-way

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Littelfuse is a global leader in circuit protection and has introduced a new line of ultra-low junction capacitance protection thyristors. The SDP series of SIDACtor® devices are designed for use in broadband and xDSL telecom equipment, offering powerful overvoltage protection without compromising signal integrity or connection speed. These thyristors are packaged in a compact SOT23-6 format, making them ideal for high-density PCB designs.

The SDP series utilizes patent-pending semiconductor effusion technology, which reduces junction capacitance by 45% compared to traditional clamp-type devices like TVS diodes. This results in faster response times during voltage surges, minimizing overshoot and improving overall protection against ESD, lightning strikes, and power failures. The devices are particularly suited for three-level or line driver side protection in VDSL 2, ADSL2, and ADSL2+ applications, as well as general I/O protection.

When a surge exceeds the cornering voltage, the effusion device acts as a shunt, providing a low-impedance path to divert transient energy away from sensitive components. In contrast, clamp devices limit the voltage to a fixed level once the breakdown point is reached. The SDP series ensures quicker response times than conventional clamping solutions, maintaining signal quality while delivering superior surge protection.

"The SPD Series SOT23-6 is the lowest-capacitance and fastest-response surge protection device available on the market," said Betty Li, Global Product Manager for the SIDACtor product line at Littelfuse. "This product allows engineers to achieve faster surge suppression than clamped devices, without sacrificing signal integrity—making it an ideal choice for modern telecom and industrial applications."

Key Features:

• Prevents xDSL driver chip failure with a galvanic response to surges up to 29V in a 250V/μs environment
• Provides up to 30A surge protection for low-power AC applications
• Offers fast response time to protect against coupling damage surges from small signal isolation transformers

Availability:

The SDP SOT23-6 SIDACtor protection thyristors are available in reel packaging, with 3,000 units per reel. Large orders can be placed through authorized Littelfuse distributors worldwide. For a complete list of authorized dealers, visit Littelfuse.com.