The **DMMT3904-TP** is a specialized electronic component manufactured by Micro Commercial Components (MCC). It consists of two NPN general-purpose transistors housed in a single surface-mount package, designed for switching and amplification applications. --- ### 1. Key Technical Specifications The DMMT3904-TP essentially contains two 2N3904-type transistors. Below are the primary electrical characteristics per transistor: | Parameter | Symbol | Maximum Rating | | :--- | :--- | :--- | | Collector-Emitter Voltage | $V_{CEO}$ | 40 V | | Collector-Base Voltage | $V_{CBO}$ | 60 V | | Emitter-Base Voltage | $V_{EBO}$ | 6.0 V | | Collector Current (Continuous) | $I_C$ | 200 mA | | Power Dissipation | $P_D$ | 200 mW | | Operating Temperature | $T_J$ | -55 to +150 °C | --- ### 2. Internal Configuration and Package The "T" in the part number often signifies a dual-transistor configuration. In this specific part: * **Package Type:** SOT-563 (ultra-small surface mount). * **Internal Layout:** It contains two independent NPN chips. This is often used for: * **Complementary Pairs:** When used alongside its PNP counterpart (DMMT3906). * **Matched Pairs:** Used in differential amplifiers where thermal tracking between the two transistors is required. * **Space Saving:** Reducing component count on a PCB by replacing two SOT-23 packages with one SOT-563. --- ### 3. Application Use Cases Because it is a high-speed switching transistor with low capacitance, it is commonly found in: 1. **Signal Processing:** Small signal amplification. 2. **Digital Switching:** Acting as a gate or driver for LEDs and small relays. 3. **Current Mirrors:** Due to the transistors being on the same substrate, they share similar thermal properties, making them ideal for current mirror circuits. --- ### 4. Comparison Table: DMMT3904 vs. Standard 2N3904 | Feature | Single 2N3904 | DMMT3904-TP | | :--- | :--- | :--- | | **Quantity** | 1 Transistor | 2 Transistors | | **Footprint** | Usually SOT-23 or TO-92 | SOT-563 (Very Small) | | **Thermal Tracking** | Poor (Separate packages) | Excellent (Shared package) | | **Max Current** | 200 mA | 200 mA (Per element) | --- ### 5. Pinout Example (SOT-563) ```text ---Top View--- | 6 5 4 | | C2 B2 E1 | <-- Pin Functions | | | E2 B1 C1 | | 1 2 3 | -------------- ```