The **LR9103G-12-AF5-R** is a low-dropout (LDO) linear voltage regulator manufactured by UTC (Unisonic Technologies Co.). It is designed for applications requiring high precision and low noise in a compact form factor. --- ### ## Technical Specifications | Parameter | Specification | | :--- | :--- | | **Output Voltage** | 1.2V (Fixed) | | **Input Voltage Range** | 2.2V to 6.0V | | **Output Current** | 300mA (Maximum) | | **Dropout Voltage** | Typically 270mV @ 300mA | | **Package Type** | SOT-25 (AF5) | | **Quiescent Current** | 50µA (Typical) | | **Shutdown Current** | < 1.0µA | --- ### ### Key Features * **Low Dropout Voltage:** Minimizes power dissipation, making it ideal for battery-powered devices. * **Enable Function:** Includes an ON/OFF control pin to reduce power consumption when the device is in standby. * **Built-in Protections:** * **Over Current Protection:** Limits output current to prevent damage during a short circuit. * **Thermal Shutdown:** Automatically turns off the IC if the junction temperature exceeds safety limits. * **Stability:** Designed to be stable even with low-ESR ceramic capacitors. --- ### ### Part Number Breakdown Understanding the suffix codes helps identify the specific variant: 1. **LR9103G**: Base model series. The "G" usually denotes **Halogen-Free** (Green) construction. 2. **-12**: Indicates the fixed output voltage of **1.2V**. 3. **-AF5**: Refers to the package type (**SOT-25**). 4. **-R**: Indicates **Tape & Reel** packaging for automated assembly. --- ### ### Typical Application Circuit The device requires minimal external components for operation: ```c Input Voltage (Vin) ----[ IN ]-------[ OUT ]---- Output (1.2V) | | [C_in: 1uF] [C_out: 1uF] | | Enable Signal (EN) ----[ EN ] [ GND ]---- Ground ``` ---