The **78R10API** is a specialized low-dropout (LDO) linear voltage regulator. It belongs to the "78R" series, which distinguishes itself from standard 78xx regulators by adding a **fourth pin** used for ON/OFF control (remote switching). --- ### 1. General Specifications The 78R10API is designed to provide a stable 10V output while allowing the system to electronically toggle the power. | Feature | Specification | | :--- | :--- | | **Output Voltage** | Fixed +10V DC | | **Output Current** | Up to 1.0 Ampere | | **Dropout Voltage** | Low (typically 0.5V) | | **Input Voltage (Max)** | Approx. 35V | | **Package Type** | TO-220F (Full-mold/Insulated) | | **Control Pin** | High level = ON / Low level = OFF | --- ### 2. Pin Configuration Unlike standard three-terminal regulators (Input, Ground, Output), this component has four pins. | Pin Number | Name | Description | | :---: | :--- | :--- | | **1** | **Vin** | Unregulated DC Input Voltage | | **2** | **Vout** | Regulated +10V Output | | **3** | **GND** | Ground (Common) | | **4** | **V_ctrl** | ON/OFF Control (TTL/CMOS compatible) | --- ### 3. Key Technical Features * **Remote Control Function:** By applying a voltage to Pin 4 (usually above 2.0V), the regulator activates. This is ideal for standby modes in electronics like TVs or audio systems to save power. * **Over-Current Protection:** Built-in circuitry prevents the device from burning out if the output is shorted. * **Thermal Shutdown:** If the internal temperature exceeds safe limits (usually 150°C), the device shuts itself off. * **Low Dropout:** It can maintain a 10V output even if the input voltage is only slightly higher (e.g., 10.5V), making it more efficient than standard 7810 regulators. --- ### 4. Basic Application Circuit The circuit requires minimal external components for stability. ```text Input (Vin) ----[ 78R10API ]---- Output (10V) | | Control -------/ \------- Ground ``` * **Input Capacitor:** Usually 0.33µF or higher to filter high-frequency noise. * **Output Capacitor:** Usually 47µF or higher (Electrolytic) to ensure stability and improve transient response. --- ### 5. Common Use Cases 1. **Standby Power Supplies:** In consumer electronics where the main CPU needs to turn peripheral power rails on/off. 2. **Audio Equipment:** To isolate power to specific stages to reduce noise when not in use. 3. **Industrial Controllers:** Where remote logic signaling is used to manage power distribution.