The **LR1102BG-28-AF5-R** is a low-dropout (LDO) linear regulator manufactured by UTC (Unisonic Technologies Co.). It is designed for low-power applications requiring a stable voltage supply and a compact form factor. --- ### ## Technical Specifications The table below outlines the core electronic characteristics of the component: | Parameter | Specification | | :--- | :--- | | **Output Voltage** | 2.8V (Fixed) | | **Output Current** | 300mA (Max) | | **Dropout Voltage** | ~300mV @ 300mA | | **Input Voltage Range** | Up to 6V | | **Quiescent Current** | ~50µA | | **Package Type** | SOT-25 / SOT-23-5 | | **Accuracy** | ±2.0% | --- ### ## Part Number Breakdown Understanding the nomenclature helps identify specific features of this variant: * **LR1102**: Base series (High PSRR, Low Noise LDO). * **B**: Includes an **Enable (EN)** pin and an **Auto-Discharge** function. * **G**: Halogen-free and Lead-free (Green). * **28**: Represents the fixed output voltage of **2.8V**. * **AF5**: Refers to the physical package style (**SOT-25**). * **R**: Tape and Reel packaging for automated assembly. --- ### ## Key Features & Protection 1. **Low Dropout:** Allows the device to regulate 2.8V even when the input battery voltage drops very close to the output level. 2. **Enable Pin (EN):** Allows the system to turn the regulator on or off to conserve battery life. 3. **Auto-Discharge:** When disabled, it internally discharges the output capacitor to ensure the output voltage drops to zero quickly. 4. **Protections:** Built-in **Current Limit** (to prevent damage from shorts) and **Thermal Shutdown** (to prevent damage from overheating). --- ### ## Typical Application Circuit The device requires minimal external components to function. Below is a standard pin configuration: ```text Pin 1: VIN (Input Supply) Pin 2: GND (Ground) Pin 3: EN (Enable - High to turn on) Pin 4: NC/BP (No connection or Bypass Cap) Pin 5: VOUT (2.8V Output) ``` **Recommended Capacitors:** - **Cin:** 1.0µF Ceramic - **Cout:** 1.0µF Ceramic (Low ESR)