## MMBT4403-AE3-R: Electronic Component Overview The **MMBT4403-AE3-R** is a widely used **PNP General Purpose Transistor** designed for low-power switching and amplification applications. It is the surface-mount (SMD) equivalent of the classic 2N4403 through-hole transistor. ### 1. Key Technical Specifications | Parameter | Symbol | Value | Unit | | :--- | :--- | :--- | :--- | | **Polarity** | Type | PNP | - | | **Collector-Emitter Voltage** | $V_{CEO}$ | -40 | V | | **Collector-Base Voltage** | $V_{CBO}$ | -40 | V | | **Emitter-Base Voltage** | $V_{EBO}$ | -5.0 | V | | **Continuous Collector Current** | $I_C$ | -600 | mA | | **Power Dissipation** | $P_D$ | 350 | mW | | **DC Current Gain** | $h_{FE}$ | 100 - 300 | (at -150mA) | | **Transition Frequency** | $f_T$ | 200 (Min) | MHz | --- ### 2. Package and Part Number Breakdown The "AE3-R" suffix typically refers to specific manufacturing and packaging standards: * **MMBT4403**: The core part number (PNP Small Signal Transistor). * **AE3**: Usually denotes the **SOT-23** package type. * **R**: Generally signifies "Tape & Reel" packaging for automated assembly. ### 3. Pin Configuration (SOT-23) | Pin Number | Function | | :---: | :--- | | 1 | **Base** | | 2 | **Emitter** | | 3 | **Collector** | --- ### 4. Typical Applications Due to its moderate current handling (-600mA) and high switching speed, it is commonly used in: * **Switching Circuits**: Driving LEDs, relays, or small motors. * **Signal Amplification**: Small signal audio or RF pre-amplifiers. * **Inverter Circuits**: Often paired with its NPN complement, the **MMBT4401**. * **Power Management**: Used in voltage regulation or load switching. --- ### 5. Complementary NPN Pair For push-pull amplifier stages or H-bridge circuits, the MMBT4403 is frequently paired with the **MMBT4401** (NPN).