Overview
Two features are combined to build this electronic speed control (ESC) for brushed motors which includes a high-rate ESC with a brake and a high-rate 12A ESC with as receiver battery eliminator circuit (BEC).
Explanation
The design of this project does not include any microprocessors which requires programming using specialized equipment and it uses off-the-shelf components for being an analog type. The assembly produces not as small or as light as many commercially available ESCs but it is smaller than many other DIY designs since no surface-mount parts were used. It ranges from small Speed 400 sport planes to hot line sailplanes, making it versatile for several applications.
An LM339 quad voltage comparator IC is the main component which contains four independent voltage comparators. This results to having an open-collector output which can either be low or floating. A pull-up resistor would be required for going to a high voltage. The chip isolates the rest of the ESC from variations between brands of receivers as it acts as an input buffer. The setting of the throttle determines the percentage of time that the integrator voltage will exceed the triangle wave.
