The **78D24L-TM3-R** is a specific part number for a linear voltage regulator, typically manufactured by UTC (Unisonic Technologies). This component belongs to the "78xx" family of fixed-output positive voltage regulators. --- ### 1. General Specifications The part is designed to provide a stable, fixed output voltage from a higher, fluctuating input voltage. | Parameter | Specification | | :--- | :--- | | **Output Voltage** | +24V DC | | **Output Current** | Up to 500mA (standard for the 'D' variant) | | **Package Type** | TO-252 (DPAK) | | **Polarity** | Positive | | **Protection** | Thermal Overload & Short Circuit Protection | --- ### 2. Part Number Breakdown Understanding the suffix codes helps in identifying the exact physical and electrical characteristics: * **78**: Positive Voltage Regulator family. * **D**: Indicates the current rating (typically 0.5A for the 'D' series in this context). * **24**: The fixed output voltage (24 Volts). * **L**: Often indicates "Lead-free" (RoHS compliant) or specific low-dropout characteristics depending on the manufacturer's datasheet. * **TM3**: Refers to the **TO-252** package (also known as DPAK), which is a surface-mount power package. * **R**: Indicates **Tape & Reel** packaging for automated assembly. --- ### 3. Key Technical Features * **Internal Current Limiting:** Prevents the device from burning out if the load draws too much power. * **Thermal Shutdown:** The device will automatically turn off if it becomes too hot. * **Safe Area Protection:** Protects the output transistor from damage under severe operating conditions. * **No External Components:** While capacitors are recommended for stability, it does not require external resistors to set the voltage. --- ### 4. Typical Application Circuit To ensure stability and filter out noise, it is standard practice to use bypass capacitors. ```markdown Input Voltage (e.g., 27V-35V) │ ├───[ + ] In (Pin 1) │ │ [C1] [78D24] │ │ ├───[ - ] GND (Pin 2 / Tab) │ │ [C2] │ │ ├───[ + ] Out (Pin 3) ---> Stable 24V DC │ GND ──┴─────────────────────────── ``` * **C1 (Input Capacitor):** 0.33µF (Ceramic or Tantalum). * **C2 (Output Capacitor):** 0.1µF (Ceramic) to ensure high-frequency stability. --- ### 5. Common Use Cases * **Industrial Controls:** Powering 24V PLC components or sensors. * **Power Supplies:** Post-regulation for AC/DC adapters. * **Telecommunications:** Regulating power rails in networking equipment.