2N7002 | Datasheet | Pinout | Equivalent

2N7002 Circuit

2n7002 circuit Picture

The 2N7002 is an N-channel enhancement MOS that is often used in circuit design, and most manufacturers make the device in TO-92 or SOT-23 packages. 2N7002’s biggest advantage is its low threshold voltage (VGS(th) in the range of 1~2.5V, typical value is 2V) and excellent small-current drive capability (a small current can make the transistor conductive), which is usually used in low-power circuits, switching circuits, level-shifting circuits, etc. The 2N7002 is an N-channel enhancement MOS that is often used in circuit design. ), and are commonly used in low-power circuits, switching circuits, level shifting circuits, and other applications.
Next, analyse the small-signal amplifier circuit consisting of 2n7002

2n7002 small signal amplifier circuit diagram

The input of the circuit is a frequency of 1KHz, amplitude of 50mV sine wave signal, after 2n7002 amplification output a 1000mV sine wave, 1000/50 = 20, you can calculate the amplification gain of 20 times (waveform shown in the figure below); but this multiplier is not the transistor’s maximum amplification multiplier, amplification multiplier is closely related to the design of the circuit; for example, will increase R2 to 1MΩ, the amplitude of the input signal to 40mV, the output signal can be 1094mV. R2 increased to 1MΩ, the amplitude of the input signal is changed to 40mV, the output signal can reach 1094mV. small signal gain of about 25 times.

Input and output waveforms