Littelfuse Announces 800 V N-Channel D-Mode MOSFET in Modified SOT-223-2L Package

Littelfuse has introduced a new 150 mA, 800 V, 45 Ohm, Small Power N-Channel Depletion Mode MOSFET CPC3981Z. In contrast to the conventional SOT-223 packaging, the SOT-223-2L package of this novel product exhibits the absence of the middle pin. This causes the distance between the drain and gate pins to increase from 1.386 millimeters to over 4 millimeters. In higher voltage applications, such as power factor correction (PFC) startup circuits or switch mode power supplies (SMPS), the extended creepage distance is advantageous because it eliminates the necessity for expensive conformal coating or potting, which is undesirable for designers.

The modified SOT-223-2L package of the CPC3981Z is its defining characteristic; it enables designers to utilize a small discrete device while still satisfying the extended creepage distance requirements for higher voltage applications. The cost reductions are made possible by the CPC3981Z’s increased circuit robustness due to its greater creepage distance. The 800 V blocking voltage rating of the CPC3981Z renders it highly suitable for implementation in various sectors such as energy, telecommunications, industrial, and LED illumination.

Such applications encompass:

● Normally ON switches

● Power supplies

● Startup circuits

● Solid-state relays

● Current regulators

● Constant current sources.

A more compact printed circuit board (PCB) layout is made possible as a result of the increased distance between the depletion mode MOSFET pins. This distance also makes it easier to control the isolation of power supply with wide input voltages.