## Overview of the PSA05R-090-R The **PSA05R-090-R** is a specialized AC/DC wall adapter manufactured by **Phihong**. It is part of the PSA05R series, designed for international versatility through interchangeable input prongs. This specific model provides a regulated 9V DC output. --- ### Technical Specifications | Parameter | Specification | | :--- | :--- | | **Output Voltage** | 9V DC | | **Output Current** | 0.56A (560mA) | | **Power Rating** | 5 Watts | | **Input Voltage Range** | 90 ~ 264 VAC (Universal) | | **Input Frequency** | 47 ~ 63 Hz | | **DC Connector Size** | 2.1mm x 5.5mm (Center Positive) | | **Efficiency Level** | Level VI | --- ### Core Electronic Components & Features The device utilizes a **Switching Mode Power Supply (SMPS)** architecture. Below are the key electronic aspects of its design: #### 1. Input Rectification and Filtering * **Bridge Rectifier:** Converts the AC input into a high-voltage DC signal. * **Filter Capacitors:** Smooth the rectified DC to provide a stable high-voltage rail for the switching circuit. #### 2. Power Conversion (Switching) * **PWM Controller IC:** Regulates the output by adjusting the duty cycle of the high-frequency switching transistor (usually a MOSFET). * **Isolation Transformer:** Steps down the high-voltage DC to the required 9V level while providing galvanic isolation between the AC mains and the DC output for safety. #### 3. Output Regulation * **Schottky Diode:** Rectifies the high-frequency AC coming from the transformer back into DC. * **Output Capacitors:** Lower the ripple voltage to ensure a clean 9V signal. * **Optoisolator:** Provides feedback from the output side back to the PWM controller on the input side, maintaining constant voltage even as the load changes. --- ### Safety and Compliance The "R" suffix often denotes specific regulatory compliance or RoHS (Restriction of Hazardous Substances) status. This unit typically features: * **Short Circuit Protection:** Prevents damage if the output leads are crossed. * **Over-Voltage Protection:** Shuts down if internal components fail to prevent damaging the connected device. * **Interchangeable AC Clips:** Allows the use of US, UK, EU, or AU prongs (sold separately). --- ### Connector Schematic The standard DC barrel plug used on this model follows the convention below: ```text Outside (Sleeve): Negative (-) Inside (Tip/Center): Positive (+) Size: 2.1mm ID / 5.5mm OD ```