What is an ESC and a UBEC? | Know The Basics

UBEC and ESC KDE Direct























Let’s get geeky. In this article, we explain the differences between a UBEC and an ESC and the importance of both for your next custom drone or technical project.

Defining ESC

An ESC (electronic speed controller) is used for controlling the brushless motor. It is the direct link between the flight-controller (brains of the drone) and the throttle control of the motor for stability. The ESC has an internal MCU (microprocessor) that controls high-frequency switching ICs that converts DC power (battery power) into three-phase power to operate the BLDC motor.  As technology continues to advance into new control algorithms and communication protocols, the ESC will also be able to communicate direct with the flight-controller for live-telemetry data, error messages, and other signals during operation.

Defining UBEC

A UBEC (universal battery eliminator circuit) is purely a device that converts high-voltage (such as 25V from a 6S LiPo) to lower voltages to allow the full UAS to be powered from one primary battery source. Since most electronics require 5V, 6V, 8V, or 12V, this device is used to power these devices from sources of power of significantly higher-voltage. In some ESCs, there is an internal BEC that provides this power; but with the KDE Direct UAS ESCs, electronics are OPTO-isolated.

This means that the power of the ESC is isolated completely from any power that can pass to the flight-controller, so an internal BEC isn’t incorporated. Rather, as is best practice for drones, the power for flight-electronics and cameras are provided via secondary electronics, such as a UBEC, to maintain isolation between electronics and keep any noise and interference from affecting flight performance.

UBEC is generally the term for switching-regulators that can handle high-currents (>5A) and higher-voltage drops (such as from 35V to 5V).

BEC (battery eliminator circuit) is generally the term for linear-regulators that help reduction in smaller voltages, such as from 12V to 5V. A linear-regulator uses resistors to dump off the extra voltage as heat, which is inefficient, where a switching-regulator like the KDEXF-UBEC22 uses high-frequency switching circuits to reduce voltage efficiently and without significant generation of heat and lost energy.

KDE Direct ESC | KDE-UAS125UVC

125A+UHV Electronic Speed Controller (ESC) for Multi- and Single-Rotor (UAS) Series

Our UAS UVC series brings next-generation technology for UAS and multi-rotor operation to life. It includes an all-aluminum 6061-T6 case for cool-running temperatures so the ESC can be used in a wide-range of harsh environments thanks to its IP66 certification for all-weather operation. It also comes preloaded with the latest production firmware, including:

  • Regenerative braking for less “float” during flight
  • Temperature-controlled synchronous rectification for smooth-running motors at low-throttle, plus faster response under heavy loads and reduced operating temperatures
  • Dynamic timing and startup power for smooth, precision-controlled startup without response lag or stuttering
  • Increased drive and throttle frequency resolution for high-accuracy, linear throttle response
  • Motor synchronization for steady throttle control and frequency-matched startup protocols

KDE Direct UBEC | KDEXF-UBEC22

22A+ Battery Eliminator Circuit (UBEC) for Multi- and Single-Rotor (UAS) Series

The KDE Direct UBEC series is designed for operation of multiple electronics and other high-power systems. They are commonly needed when linear BECs aren’t capable of handling power requirements (such as those included in off-brand ESCs) or when using high-grade, OPTO-isolated ESCs (such as the KDE Direct UAS Electronic Speed Controller (ESC) Series).

Our UBEC series is compatible with 2S LiPo - 8S LiHV (35V Max) power systems for clean, voltage-regulated power needed for critical flight electronics and peripheral equipment like 12V aerial photography or high-end UAS equipment. The KDEXF-UBEC22 eliminates the need for an external battery pack. It also allows for simple adjustment of the regulated output voltage for direct compatibility with your electronics and power applications.

KDE Direct

KDE Direct’s ESC and UBEC Series are designed and engineered in the United States to provide you with best-in-class power, performance, and efficiency. From utilizing design redundancy standards and fail-safes, to payload capacity and thrust performance, KDE Direct components are engineered for higher efficiency, higher payloads, and longer flight times that push the limits of today’s technology.

The KDE Direct UAS Multi-Rotor Electronic Speed Controller (ESC) and Universal Battery Eliminator Circuit (UBEC) Series present high-quality and engineered electronics, specific for multi-rotor and UAS applications. These are designed to provide market-leading performance tuned and optimized for the KDE Direct UAS Multi-Rotor Brushless Motor Series.


Looking to build a new project with your new knowledge? For optimal selection of KDE Direct equipment, please reference the Build Your System application or make a Custom Design Inquiry.


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