2N7000

Applications

The 2N7000 has been referred to as a "FETlington" and as an "absolutely ideal hacker part." | author-link = Don Lancaster

A typical use of these transistors is as a switch for moderate voltages and currents, including as drivers for small lamps, motors, and relays. In switching circuits, these FETs can be used much like bipolar junction transistors, but have some advantages:

• high input impedance of the insulated gate means almost no gate current is required
• consequently no current-limiting resistor is required in the gate input
• MOSFETs, unlike PN junction devices (such as LEDs) can be paralleled because resistance increases with temperature, although the quality of this load balance is largely dependent on the internal chemistry of each individual MOSFET in the circuit

The main disadvantages of these FETs over bipolar transistors in switching are the following:

• susceptibility to cumulative damage from static discharge prior to installation
• circuits with external gate exposure require a protection gate resistor or other static discharge protection
• Non-zero ohmic response when driven to saturation, as compared to a constant junction voltage drop in a bipolar junction transistor

Other devices

The 2N7002 is a surface-mount variant of the 2N7000. The 2N7002K variant integrates protection diodes between the gate and source for electrostatic robustness, and the 2N7002AK-Q additionally is marketed as "automotive qualified" and "logic-level compatible".

Many other n-channel MOSFETs exist. Some part number are BS170, VQ1000J, and VQ1000P. They may have different pin outs, packages, and electrical properties. The BS250P is "a good p-channel analog of the 2N7000."

References

References

1. "2N7002K (N-channel TrenchMOS intermediate level FET)".
2. "2N7002AK-Q (60 V, N-channel Trench MOSFET)".