The **GS-R4002** is a high-efficiency step-down (buck) switching regulator module, historically manufactured by STMicroelectronics. These modules were designed to simplify power supply design by integrating most of the required components into a single, compact package. --- ### 1. Technical Specifications The GS-R4002 belongs to the GS-R series of power modules. Here are the core electronic characteristics: | Feature | Specification | | :--- | :--- | | **Input Voltage Range** | 7V to 40V DC | | **Output Voltage** | 5.1V (Fixed) | | **Output Current** | 4.0 Amperes (Max) | | **Efficiency** | Typically 75% to 85% | | **Switching Frequency** | ~100 kHz | | **Package Type** | SIP (Single In-line Package) or DIP-style module | --- ### 2. Internal Components & Architecture The "electronic parts" within the GS-R4002 module are integrated to form a complete DC-DC converter. While encapsulated, the internal circuit consists of: * **Switching Controller:** A PWM (Pulse Width Modulation) IC that regulates the timing of the energy transfer. * **Power MOSFET/Transistor:** Acts as the high-speed switch to chop the input DC voltage. * **Power Inductor:** Stores energy during the "on" cycle and releases it during the "off" cycle. * **Schottky Diode:** Provides a path for the current when the switch is open (freewheeling diode). * **Filter Capacitors:** Internal ceramic or tantalum capacitors to reduce input/output ripple. --- ### 3. Key Features * **Short Circuit Protection:** The module includes internal current limiting to prevent damage during a fault. * **Thermal Shutdown:** Automatically turns off if the internal temperature exceeds safe operating limits. * **No External Heat Sink:** For many applications within rated specs, the module's metal casing or substrate provides sufficient cooling. * **Remote Inhibit:** Often features a pin to allow the user to turn the output on or off via a logic signal. --- ### 4. Connection Pinout (Typical) Most GS-R series modules follow a standard pin configuration: | Pin Number | Function | Description | | :--- | :--- | :--- | | 1 | **+ Vin** | Positive Input Voltage | | 2 | **Input Ground** | Common Return for Input | | 3 | **Output Ground** | Common Return for Output | | 4 | **+ Vout** | Regulated 5.1V Output | | 5 | **Inhibit** | Logic control (Enable/Disable) | --- ### 5. Application Usage The GS-R4002 is commonly used in industrial environments where a stable 5V rail is needed from a higher voltage source (like a 24V industrial bus). It is ideal for: * Microprocessor power supplies. * Industrial automation controllers. * Telecommunications equipment.