# Fluid Ardule Power Supply Design (5V SMPS Based) ## 1. Overview This design defines a stable power architecture using a 5V 8A SMPS to drive: - Raspberry Pi + TFT LCD - Powered USB hub - Arduino UNO (via USB) - Audio interface (Mackie Onyx Producer 2-2) - MIDI keyboard controller Goals: - Stable 5V delivery - Low noise for audio - Expandable structure - Easy maintenance --- ## 2. Power Architecture ```` AC 220V → SMPS (5V 8A) → DC Distribution Block ├─ Raspberry Pi (direct 5V) │ └─ TFT LCD ├─ Powered USB Hub │ ├─ Arduino UNO (USB) │ ├─ DAC (Onyx 2-2) │ └─ MIDI Keyboard └─ Expansion ```` --- ## 3. Design Principles ### Star Topology Each device is powered independently from the distribution block. ### Power Separation - Pi: direct power line - USB hub: separate line - UNO: powered via USB only ### Voltage Setting - Set SMPS to 5.1V (no load) --- ## 4. Current Budget Total estimated: 2.5A ~ 3.5A → 8A SMPS provides sufficient margin --- ## 5. Recommended Components ### SMPS - Mean Well LRS-50-5 (5V 10A) - Equivalent 5V 8~10A industrial PSU ### Distribution Block - Screw terminal block (5~10 outputs) ### Wiring - Main: AWG18 - Branch: AWG20 - Small loads: AWG22 ### USB Hub - Powered hub with external DC input ### Capacitors - 1000µF electrolytic - 0.1µF ceramic --- ## 6. Grounding - Earth (AC) must be connected - DC ground must follow star topology --- ## 7. Important Notes - Do NOT power UNO via 5V pin when USB is connected - Do NOT daisy-chain power - Ensure proper ventilation for SMPS - Use short, thick wires for Pi --- ## 8. Summary SMPS → Distribution Block → Separate lines to Pi and USB hub UNO powered via USB This ensures stability, safety, and audio quality.