Surface Mount, Low Current Consumption, Low Dropout Voltage Linear Regulator ICs The part **SI-3120KM** is manufactured by **SANKEN**. Below are the specifications, descriptions, and features based on the available knowledge:  

### **Specifications:**  
- **Type:** Switching Regulator IC  
- **Output Voltage:** Adjustable  
- **Output Current:** Up to 3A  
- **Input Voltage Range:** 4.5V to 40V  
- **Switching Frequency:** 100kHz (typical)  
- **Efficiency:** High efficiency design  
- **Package:** TO-220 (5-pin)  
- **Operating Temperature Range:** -40°C to +125°C  
- **Protection Features:** Overcurrent protection (OCP), thermal shutdown  

### **Descriptions:**  
The **SI-3120KM** is a step-down (buck) switching regulator IC designed for high-efficiency power conversion. It is suitable for a wide range of applications, including industrial, automotive, and consumer electronics. The adjustable output voltage feature allows flexibility in design.  

### **Features:**  
- **Wide Input Voltage Range (4.5V–40V)**  
- **High Output Current Capability (3A)**  
- **Built-in Overcurrent Protection**  
- **Thermal Shutdown Protection**  
- **Compact TO-220 Package**  
- **Adjustable Output Voltage**  
- **Stable Operation with External Components**  

For detailed application notes or schematics, refer to the official **SANKEN datasheet**.

Surface Mount, Low Current Consumption, Low Dropout Voltage Linear Regulator ICs