## 2N7002L: N-Channel Enhancement Mode MOSFET The **2N7002L** is a small-signal, N-channel enhancement mode Field-Effect Transistor (FET) utilizing high-density cell design and DMOS technology. It is widely used in low-voltage, low-current switching and level-shifting applications. --- ### 1. Key Technical Specifications The following table summarizes the primary electrical characteristics of the 2N7002L: | Parameter | Symbol | Typical Value | Unit | | :--- | :--- | :--- | :--- | | Drain-Source Voltage | $V_{DS}$ | 60 | V | | Gate-Source Voltage | $V_{GS}$ | ±20 | V | | Continuous Drain Current | $I_D$ | 300 | mA | | Pulsed Drain Current | $I_{DM}$ | 800 | mA | | Gate Threshold Voltage | $V_{GS(th)}$ | 1.0 to 2.5 | V | | Static Drain-Source On-Resistance | $R_{DS(on)}$ | 2.0 - 5.0 | $\Omega$ | | Total Power Dissipation | $P_D$ | 350 | mW | --- ### 2. Pin Configuration and Package The 2N7002L is typically housed in a **SOT-23** surface-mount package, which is ideal for space-constrained PCB designs. 1. **Pin 1 (Gate):** Controls the flow of current between Drain and Source. 2. **Pin 2 (Source):** Connected to the negative supply or ground in typical N-channel configurations. 3. **Pin 3 (Drain):** Connected to the load. --- ### 3. Major Features * **High Density Cell Design:** Minimizes on-state resistance while maintaining high reliability. * **Voltage Controlled:** Unlike BJT transistors (current-controlled), the MOSFET is voltage-controlled, requiring almost no gate current once the gate capacitance is charged. * **Fast Switching:** Capable of high-speed switching transitions, making it suitable for digital logic level translation. * **ESD Protection:** Many modern versions of the 2N7002L include integrated ESD protection diodes. --- ### 4. Common Applications * **Logic Level Shifting:** Converting signals from 3.3V logic to 5V logic (or vice versa). * **Small Load Switching:** Driving LEDs, small relays, or buzzers directly from a microcontroller pin. * **Signal Conditioning:** Used in analog switches and power management circuits. * **Battery Management:** Occupies minimal space in portable electronics for power gating. --- ### 5. Implementation Example (Basic Switch) To use the 2N7002L as a switch, the Gate is connected to a GPIO pin. When the GPIO is HIGH ($> V_{GS(th)}$), the MOSFET conducts. ```cpp // Logic Control Flow If (GPIO_PIN == HIGH) { Vgs > Vgs(th); MOSFET = ON; // Current flows from Drain to Source } else { Vgs = 0; MOSFET = OFF; // High impedance state } ```