The **LR1102AL-33-AF5-R** is a low-dropout (LDO) linear voltage regulator. It is designed to provide a stable, fixed output voltage from a higher, potentially fluctuating input voltage with minimal power loss. --- ## 1. Technical Specifications Below are the primary electrical characteristics for this specific part number: | Parameter | Specification | | :--- | :--- | | **Output Voltage** | 3.3V (Fixed) | | **Max Output Current** | 300mA | | **Dropout Voltage** | ~300mV @ 300mA (Typ) | | **Input Voltage Range** | Up to 6V | | **Package Type** | SOT-25 / SOT-23-5 | | **Quiescent Current** | ~50µA | | **Operating Temp** | -40°C to +85°C | --- ## 2. Part Number Breakdown The suffixing in the part number provides specific details about the component's configuration: * **LR1102**: The series name (LDO Regulator). * **AL**: Accuracy/Version indicator (often refers to 2% output accuracy). * **33**: Represents the **3.3V** fixed output voltage. * **AF5**: Refers to the **SOT-25** (5-pin) package style. * **R**: Indicates **Tape & Reel** packaging for automated assembly. --- ## 3. Pin Configuration (SOT-25) Standard pinout for this 5-pin regulator typically follows this structure: | Pin Number | Name | Function | | :--- | :--- | :--- | | 1 | **VIN** | Input Voltage Supply | | 2 | **GND** | Ground | | 3 | **EN / CE** | Enable/Chip Enable (High = On, Low = Off) | | 4 | **NC / BYP** | No Connect or Bypass Capacitor (for noise reduction) | | 5 | **VOUT** | Regulated 3.3V Output | --- ## 4. Key Features & Applications ### Features - **Low Dropout:** Can maintain a 3.3V output even when the input voltage is as low as ~3.6V. - **Enable Function:** Includes a shutdown pin to reduce power consumption to near zero when the device is not in use. - **Protection:** Usually includes internal thermal shutdown and current limiting to prevent damage during a short circuit. ### Typical Applications - **Battery-powered devices:** Handheld scanners, IoT sensors, and wearables. - **Post-regulation:** Cleaning up noisy output from a switching power supply. - **Microcontrollers:** Providing a steady 3.3V rail for ESP32, STM32, or logic circuits. --- ## 5. Typical Application Circuit To ensure stability, LDOs require external capacitors. ```c // Basic Circuit Representation [Input 3.6V-6V] ----> [VIN] (LR1102) [VOUT] ----> [Output 3.3V] | | | [1uF Cap to GND] | [1uF Cap to GND] [GND] ```