Bi-Directional Speed Controller

Introduction

Whilst there are many commercially reversible speed controllers available, most are designed for high performance model cars or boats, and therefore are large and expensive. I wanted a lightweight ESC for fitting into a small scale boat or submarine.

Features

• Fully solid state, bi-directional output (no relay!)
• Lightweight SMD (Surface Mount Device) construction
• Up to 10A maximum motor current (with suitable output FETs)
• Automatic LVC (Low Voltage Cutoff) handles 6~12V batteries
• Throttle neutral at standard 1.5mS, or 1.37mS for offset stick
• Safety Arming. Motor won't start until throttle is set to neutral
• High frequency PWM (3KHz) for smooth and efficient control
• 1A low dropout BEC (Battery Eliminator Circuit)

Source Code, Hex file for 12F675, Eagle PCB layout file