Embedded Engineering Glossary

PCB

Printed Circuit Board

A printed circuit board (PCB) is a flat board that mechanically supports and electrically connects electronic components using conductive copper traces, pads, and layers etched onto an insulating substrate.

HDI PCB

High-Density Interconnect PCB

An HDI (high-density interconnect) PCB uses finer traces, smaller microvias, and higher wiring density than standard boards, packing more connections into less space for compact, high-performance devices.

Rigid-Flex PCB

Rigid-Flex Printed Circuit Board

A rigid-flex PCB combines rigid board sections with flexible circuit sections in one assembly, letting a board fold or bend to fit a 3D enclosure while removing connectors and cables.

Gerber Files

Gerber Format

Gerber files are the standard open format describing each layer of a PCB — copper, solder mask, silkscreen, and drill data — that fabrication houses use to manufacture the board.

Controlled Impedance

Controlled impedance is a PCB technique that sets precise trace geometry and stackup so high-speed signals see a consistent target impedance (often 50 Ω), preventing reflections and signal loss.

Signal Integrity

Signal integrity is the measure of how well an electrical signal keeps its shape as it travels through a circuit, covering reflections, crosstalk, timing, and noise that can corrupt high-speed data.

BMS

Battery Management System

A battery management system (BMS) is the electronics that monitor and protect a rechargeable battery pack — tracking voltage, current, temperature, and state of charge, and guarding against overcharge, over-discharge, and thermal runaway.

Firmware

Firmware is the low-level software programmed into a device's non-volatile memory that controls its hardware directly — the code that makes an embedded system function, sitting between the hardware and any higher-level software.

RTOS

Real-Time Operating System

A real-time operating system (RTOS) is a compact operating system that schedules tasks with deterministic, bounded timing, guaranteeing that time-critical operations run within their deadlines.

Bare-Metal

Bare-Metal Firmware

Bare-metal firmware runs directly on the microcontroller with no operating system, giving full control and minimal overhead — well suited to simple, resource-constrained, or hard real-time applications.

Bootloader

A bootloader is a small program that runs first when a device powers on, initializing hardware and loading the main firmware — and often enabling firmware updates over the air or over a serial/USB link.

BSP

Board Support Package

A board support package (BSP) is the layer of firmware — drivers, initialization code, and configuration — that adapts an operating system or application to a specific hardware board.

OTA Update

Over-the-Air Update

An over-the-air (OTA) update delivers new firmware to a deployed device remotely over its network connection, letting manufacturers fix bugs, patch security, and add features without physical access.

Embedded System

An embedded system is a computer built into a larger product to perform a dedicated function, combining a processor, memory, and I/O with firmware rather than acting as a general-purpose PC.

MCU

Microcontroller

A microcontroller (MCU) is a single chip that integrates a processor core, memory, and peripherals, designed to run dedicated firmware for real-time control in embedded products.

MPU

Microprocessor

A microprocessor (MPU) is a processor that relies on external memory and typically runs a full operating system like Linux, suited to devices needing rich UIs, networking, or heavier compute than a microcontroller.

SoC

System on Chip

A system on chip (SoC) integrates a processor, memory interfaces, and multiple peripherals — sometimes including radios, GPUs, or AI accelerators — onto a single chip to save space, power, and cost.

SoM

System on Module

A system on module (SoM) packages a processor, memory, and core support circuitry as a ready-made board that drops onto a custom carrier board, speeding development and de-risking complex processor designs.

FPGA

Field-Programmable Gate Array

An FPGA (field-programmable gate array) is a chip whose digital logic can be reconfigured after manufacturing, letting engineers implement custom hardware, high-speed interfaces, or massively parallel processing.

Edge AI

Edge Artificial Intelligence

Edge AI is machine learning that runs directly on a device at the network edge rather than in the cloud, delivering low latency, privacy, and offline operation for tasks like vision, audio, and sensor analysis.

TinyML

Tiny Machine Learning

TinyML is machine learning optimized to run on low-power microcontrollers with kilobytes of memory, enabling always-on inference — like keyword spotting or anomaly detection — within a tiny power budget.

Sensor Fusion

Sensor fusion combines data from multiple sensors — such as accelerometers, gyroscopes, and magnetometers — into a single, more accurate estimate than any one sensor could provide alone.

LPWAN

Low-Power Wide-Area Network

LPWAN (low-power wide-area network) is a class of wireless technologies — including LoRaWAN, NB-IoT, and LTE-M — built for long range and multi-year battery life at low data rates, ideal for dispersed IoT sensors.

BLE

Bluetooth Low Energy

Bluetooth Low Energy (BLE) is a short-range wireless protocol designed for very low power consumption, widely used to connect battery-powered devices like wearables and sensors to phones and gateways.

MQTT

Message Queuing Telemetry Transport

MQTT is a lightweight publish/subscribe messaging protocol built for constrained devices and unreliable networks, making it a common choice for sending IoT sensor data to the cloud efficiently.

EMC

Electromagnetic Compatibility

EMC (electromagnetic compatibility) is a device's ability to operate correctly without emitting excessive electromagnetic interference (EMI) or being disrupted by it — a mandatory requirement in most markets.

ESD

Electrostatic Discharge

ESD (electrostatic discharge) is the sudden flow of electricity between two charged objects, which can instantly damage sensitive electronics; ESD protection designs safeguard circuits during handling and use.

Functional Safety

Functional safety is the part of a system's overall safety that depends on its electronics and software working correctly, managed through standards like IEC 61508, ISO 26262 (automotive), and IEC 62304 (medical).

DFM

Design for Manufacturability

Design for manufacturability (DFM) is the practice of designing a product so it can be built reliably and cost-effectively, catching issues like tight tolerances or unavailable parts before production.

BOM

Bill of Materials

A bill of materials (BOM) is the complete, structured list of every component, part number, quantity, and reference needed to build a product — the master parts list manufacturing works from.

NPI

New Product Introduction

New product introduction (NPI) is the process of taking a validated design into volume manufacturing, covering design transfer, pilot builds, test development, and the ramp to production.