# FPV Drone Power Distribution: PDB vs AIO Wiring and Current Management
Every component on your FPV drone needs clean, stable power. How you distribute that power — through a dedicated Power Distribution Board (PDB), an All-In-One (AIO) flight controller, or a 4-in-1 ESC board — directly affects build weight, reliability, and electrical noise. This guide breaks down the options.
## The Three Power Distribution Architectures
### 1. Dedicated PDB (Legacy / Custom Builds)
A standalone PDB is a separate board that receives battery voltage and distributes it to ESCs, flight controller, VTX, camera, and receiver. Once standard, now mostly replaced by AIO solutions.
| Pros | Cons |
|—|—|
| High current capacity (200A+) | Extra weight (8-15g) |
| Replaceable independent of FC/ESC | Additional wiring complexity |
| Clean layout separation | Takes up stack space |
| Often includes LC filter | Old-school, limited modern options |
### 2. AIO Flight Controller (Modern Standard)
Most modern FPV builds use an AIO FC that integrates the PDB directly onto the flight controller board. Battery leads solder to the FC, and the board distributes power to everything.
| Pros | Cons |
|—|—|
| Saves weight (no separate PDB) | FC replacement = full rewire |
| Simplifies wiring | PCB traces carry all current |
| Common on F7/H7 boards | Current rating limited by PCB |
| Integrated current sensor | Heat concentrated on one board |
### 3. 4-in-1 ESC Board Distribution
Many 4-in-1 ESCs include a built-in power distribution section. Battery power goes to the ESC board first, then a cable harness carries regulated voltage to the FC.
| Pros | Cons |
|—|—|
| ESC handles high current directly | ESC failure may take out everything |
| FC only handles low-current electronics | ESC replacement = disconnect all motors |
| Cleanest physical layout | Harness between ESC and FC adds wiring |
## Current Rating: What Your PDB Needs to Handle
| Build Type | Peak Current Draw | Required PDB/AIO Rating |
|—|—|—|
| 5″ 4S freestyle (2207 2450KV) | 120-140A | 150A minimum |
| 5″ 6S freestyle (2207 1750KV) | 100-120A | 130A minimum |
| 7″ long-range (2508 1500KV) | 80-100A | 110A minimum |
| 3″ cinewhoop (1408 3600KV) | 40-60A | 60A minimum |
| 5″ racing (2306 2700KV) | 140-180A | 200A minimum |
## Wiring Best Practices
### Wire Gauge Selection
| Component | Recommended AWG | Notes |
|—|—|—|
| Battery leads (XT60/XT30) | 12-14 AWG | Short as possible |
| ESC power wires | 16-18 AWG | Match to ESC pad size |
| VTX power (if direct from battery) | 20-22 AWG | Add a capacitor near VTX |
| Camera / RX power | 24-26 AWG | Signal-level current |
### Capacitor Placement
A low-ESR capacitor on the battery pads is mandatory for clean power:
– 4S builds: 35V 470-1000µF
– 6S builds: 50V 470-1000µF
– Mount as close to the battery pads as physically possible
– Add a smaller 100-220µF cap at the VTX power input for video noise filtering
## Common Power Issues
| Issue | Likely Cause | Fix |
|—|—|—|
| Voltage sag under throttle | Undersized battery leads or connector | Larger gauge wire, XT60 over XT30 |
| VTX blackouts on punch-out | Insufficient capacitor | Add 1000µF low-ESR cap |
| FC brownout / reboot | 5V regulator overloaded | External BEC for high-current 5V loads |
| ESC desync at high throttle | Ripple voltage causing bad sensor reads | Larger capacitor, shorter battery leads |
## Recommended Hardware
A well-designed AIO flight controller with robust power traces, built-in current sensor, and a quality 5V/9V BEC simplifies power distribution dramatically. The SpeedyBee F7 V3 and Mamba H7 AIO boards available at [uavmodel.com](https://uavmodel.com) feature 6-layer PCBs with thick copper power planes capable of handling 150A+ continuous current — eliminating the need for a separate PDB in all but the most extreme builds.