N-Channel Depletion Mode MOSFET

The features of a single current regulator in one component
Infineon is one of the few semiconductor manufacturers worldwide to offer N-channel depletion mode MOSFETs. Compared to enhancement mode transistors, known as normally-off, depletion MOSFETs are in an on-state at zero voltage of gate-to-source (VGS), normally-on. This makes N-channel depletion MOSFETs a perfect constant current source.

N-Channel Depletion Mode MOSFET features

N-Channel Depletion Mode MOSFET Portfolio
Infineon’s range of N-channel depletion mode MOSFETs are available in voltages from 60 V up to 600 V. Thanks to the depletion type MOSFET’s special characteristics, it provides higher efficiency and ruggedness as well as a wider operating range for SMPS and LED lighting. A depletion power MOSFET can also be used as a voltage regulator.

NMOS depletion mode

NMOS depletion mode MOSFETs use electrons as the current carrier allowing conduction if there is a positive charge. PMOS MOSFETs on the other hand use holes, so a negative charge attracts positively charged holes to the channel allowing it to conduct. However, NMOS depletion mode is activated when using a negative voltage to repel the free carriers so the depletion device can no longer conduct. This is how to turn off a depletion mode MOSFET.

Depletion mode MOSFET switch

Infineon’s range of depletion mode MOSFET switches offer fast switching and small and compact design.

N-Channel Depletion Mode MOSFET Applications

Industrial applications

Areas of depletion MOSFET application include power supply startup power, over-voltage protection, in-rush-current limiter, and off-line voltage reference. With one single component it is possible to realize a simple current regulator.

Automotive applications

All N-channel depletion MOSFET products are suitable for automotive applications. In order to meet special requirements, N-channel depletion mode MOSFETs are available with VGS(th) indicator on reel.