The **B772SSL-P-AE3-R** is a specific part number for a medium-power PNP epitaxial silicon transistor. It is widely used in power management and switching applications due to its low saturation voltage and high current handling capabilities. ### 1. Technical Specifications The following table summarizes the key electrical characteristics of the B772SSL: | Parameter | Symbol | Maximum Rating | | :--- | :--- | :--- | | **Collector-Base Voltage** | $V_{CBO}$ | -40 V | | **Collector-Emitter Voltage** | $V_{CEO}$ | -30 V | | **Emitter-Base Voltage** | $V_{EBO}$ | -5 V | | **Collector Current (DC)** | $I_{C}$ | -3 A | | **Collector Current (Pulse)** | $I_{CP}$ | -7 A | | **Total Power Dissipation** | $P_{D}$ | 1 W to 2 W (varies by heatsink) | | **Junction Temperature** | $T_{J}$ | +150 °C | --- ### 2. Part Number Breakdown The suffixing on this part provides information about its packaging and classification: * **B772**: The base model number (PNP power transistor). * **SSL**: Often refers to a specific gain (hFE) classification or a "Super Small" lead variant depending on the manufacturer (likely UTC - Unisonic Technologies). * **P**: Represents the **hFE Rank** (Current Gain). For the B772 series, "P" typically denotes a gain range between **160 and 320**. * **AE3**: Refers to the **SOT-223** package type (Surface Mount Device). * **R**: Indicates **Tape & Reel** packaging for automated assembly. --- ### 3. Key Features and Applications The B772SSL is favored for its efficiency in small form factors. #### Key Features: * **Low Saturation Voltage:** $V_{CE(sat)}$ is typically only -0.3V at $I_{C}$ = -2A, which reduces power loss and heat. * **High Current:** Can handle up to 3A continuously despite its small footprint. * **Complementary Pair:** Usually paired with the **D882** (NPN version) for push-pull circuits. #### Typical Applications: * **Voltage Regulators:** Used in linear regulators for power supplies. * **Relay Drivers:** High current capacity allows it to drive mechanical relays. * **DC-DC Converters:** Used in switching power circuits. * **Audio Amplifiers:** Specifically in the output stage of low-power amplifiers. --- ### 4. Typical Footprint (SOT-223) The **AE3** code indicates an SOT-223 package. This is a surface-mount package with a large tab for heat dissipation. ```text [ Tab (Collector) ] _____________________ | | | | B772SSL | |_____________________| | | | Base Collector Emitter (1) (2/Tab) (3) ```