The is a linear DC bench power supply capable of providing an adjustable output of 0–30V and 0–5A . Known as a common entry-level laboratory tool, its story is one of simple design, accessibility, and the occasional need for enthusiast-led modifications to improve its longevity. The Core Architecture The schematic of the
Based on technical discussions and teardowns at the EEVblog Forum and Scribd , key parts include: Yh-305d Power Supply Schematic
: A low-resistance shunt resistor is used to measure current, with adjustment trimmers (like VR10 for offset and VR11 for gain) allowing for calibration. The is a linear DC bench power supply
follows a classic linear regulation design. It typically utilizes a large to step down the AC mains voltage, which is then passed through a bridge rectifier and large filter capacitors to create a raw DC voltage. follows a classic linear regulation design
: A 1N5408 diode (often labeled D1) acts as a safety measure to prevent damage from reverse current applied to the terminals. Reliability and Modifications
: An L7805CV is often used to provide a stable 5V rail for the digital display and microcontroller.