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Littelfuse CPC3981 N-Channel Depletion-Mode MOSFET Series

Realize world-class, high voltage performance

The CPC3981Z by Littelfuse is an 800 V, 100 mA, 45 Ohm, small power N-Channel Depletion Mode MOSFET which enables world-class, high voltage MOSFET performance in an economical silicon gate process.

Littelfuse’s N-channel depletion mode field effect transistors (FET) utilize a proprietary third generation vertical DMOS process which yields a robust device for high power applications with high input impedance.

These highly reliable FET devices have been used extensively in solid-state relays for industrial and telecommunications applications.

Compared to a standard SOT-223 package, this new product's SOT-223-2L package features a removed middle pin. This increases the drain-gate pin spacing from 1.386 millimeters to more than 4 millimeters. The extended creepage distance is beneficial in higher voltage applications such as switch mode power supplies (SMPS) or power factor correction (PFC) startup circuits because designers can avoid the need for costly conformal coating or potting.

SOT-223-2L Package

The key differentiator of the CPC3981Z by Littelfuse is its modified SOT-223-2L package which enables designers to meet the required extended creepage distance for higher voltage applications with a small discrete device.

With its larger creepage distance, the CPC3981Z increases circuit robustness and enables cost savings. The 800 V blocking voltage rating of the CPC3981Z makes it the ideal choice for use in industrial, energy, telecommunications, and LED lighting applications, including:

  • Normally ON switches
  • Power supplies
  • Startup circuits
  • Solid-state relays
  • Current regulators
  • Constant current sources

Key Features

  • Normally closed with no power applied
  • Low VGS(off) voltage
  • High input impedance