The A20112 is a classic linear-regulated (or in some variants, a hybrid switching-to-linear) power supply architecture. It is designed primarily for applications that require low electromagnetic interference (EMI), ultra-low output ripple, and robust tight regulation. Key Technical Specifications
Understand the difference between linear, switching, and resonant mode power supplies, as the schematic will vary significantly.
🔹 – EMI filtering & rectification (usually 110/220V AC selectable) 🔹 Switching Section – MOSFET or BJT-based chopper circuit 🔹 PWM Controller – Common ICs like UC3842/3843 or TL494 🔹 Output Rails – Often ±12V / +5V / +3.3V DC with feedback regulation 🔹 Protection – Overcurrent, overvoltage, and short-circuit sensing a20112 power supply schematic
This multi-phase design delivers three main performance advantages:
👇 Have you repaired an A20112 before? What was the most common failure? Let’s discuss below. The A20112 is a classic linear-regulated (or in
4.2 Rectification and Bulk Filtering
To help find the exact variant of your circuit, what is this A20112 power supply inside? If you are looking for specific component values or pinout configurations , let me know and I can provide those details. Share public link 🔹 – EMI filtering & rectification (usually 110/220V
AC Input ──► [EMI Filter] ──► [Bridge Rectifier] ──┬──► [Boost Stage A] (0°) ──┬──► DC Out └──► [Boost Stage B] (180°) ──┘
): Act as high-speed electronic switches driven directly by the GD1 (Gate Drive 1) and GD2 pins of the R2A20112 IC. Boost Diodes (