LogoLogo
  • Welcome!
  • Mission Statement
  • Contributing Guidelines
    • Embed CADs in Wiki Articles
  • VEX Worlds Livestream Archive
    • VEX U
    • V5RC High School
    • V5RC Middle School
    • VIQRC Middle School
    • VIQRC Elementary School
    • JROTC
  • ⚙️Hardware
    • Design Fundamentals
      • Gear Ratios
      • Internal Forces (Stress)
      • Torque
      • RPM
      • Center of Mass
    • Introduction to VEX Parts
      • Structure
        • C-Channels and Angles
        • Fasteners
        • Retainers
        • Gussets and Brackets
        • Bearings
        • Plate Metal and Flat Bars
      • Motion
        • High Strength Components
        • Gears and Sprockets
        • Traction Wheels
        • Mecanum Wheels
        • Omnidirectional Wheels
        • Flex Wheels
    • Robot Decorations
      • Part Dyeing
      • Metal Coloring
      • License Plate Holders
    • Lifts
      • Double Reverse Four Bar (DR4B or RD4B)
      • Four Bar
      • Scissor Lift
      • Six Bar
      • Other Lifts
      • Best Practices
    • Shooting Mechanisms
      • Catapult
      • Flywheel
      • Linear Puncher
    • Drivetrains
      • Tank Drive
      • Mecanum Drive
      • Holonomic Drive
      • Designing a Drivetrain
      • Best Practices
    • Pivots & Joints
    • Pneumatics
      • Best Practices - Pneumatics
    • Intakes
    • Flip Out Mechanisms
    • Defensive Mechanisms
    • Misc. Building Techniques
    • VexU
      • Common Manufacturing Techniques
        • 3D Printing
        • Laser Cutting
      • Custom Manufactured Parts Library
      • Commercial Off The Shelf Parts Library
  • 👑Team Administration
    • New Team Resources
      • Creating The Team
      • Gaining Interest for Robotics Teams
      • Attending Competitions
        • Elimination Bracket
    • Team Dynamics
      • Organization Structure and Longevity
      • Member Allocation and Management
      • How *Not* To Run a Team
    • Team Finances
      • One-Year Team Financial Breakdown
      • Funding Your Teams
    • Hosting Competitions
      • Live Streaming
      • Tournament Manager
        • Competition Electronics
        • Creating a Tournament
        • Tools
          • Field Set Control
          • Connecting Mobile Devices
          • Connecting Raspberry Pis
        • Match Control
          • Inputting Match Scores
          • Inputting Skills Scores
          • Inputting Scores on TM Mobile
        • Displays
        • Alliance Selection
      • Additional Event Partner Resources
    • VexU Organization Management
      • Getting Started in VexU
      • Team / Personnel Management
      • Volunteering At Local Events
  • 📚The Judging Process
    • The Engineering Design Process
      • Test and Refine
    • The Engineering Notebook
      • Segments of the Notebook
      • BLRS2 '23-'24 Engineering Notebook
      • Integrating Inventor Models into Documentation
      • Engineering Notebook Rubric Breakdown
    • The Interview
      • Interview Rubric Breakdown
    • Using Notion for an Engineering Notebook
      • How to Setup a Notebook
      • How to Create Entries
      • How to Export a Notebook
      • Purdue SIGBots Notion Template
        • Game Analysis
        • Identify The Problem
        • Brainstorm Solution
        • Select Best Approach & Plan
        • Build Log
        • Programming Log
        • Testing Solution
        • Tournament Recap
        • Innovative Feature
  • 🖥️VEX CAD
    • CAD Programs
      • Inventor
      • Fusion 360
      • Solidworks
      • OnShape
      • Protobot
    • Making a Chassis
      • Inventor Chassis: The Basics
        • Installation
        • User Interface Overview
        • Dark Mode
        • Assemblies
        • Placing Parts
        • Navigating CAD
        • Changing Visual Style
        • Grounding
        • Connecting Two C-Channels
        • Modifying Existing Constraints
        • Toggling Visibility on Existing Parts
        • Completing Half of the Chassis
          • Inner Drive Channel
          • Bearing Flats
          • Motors
          • Wheels
          • Sprockets
          • Spacers, Washers and Standoffs
          • Spacers Cont.
        • Creating Mid-Plane
        • Mirroring
      • Inventor Chassis: Best Practices
        • File Structure
        • Subassemblies
        • Wheel Subassembly
        • Origin Planes
        • Cross Brace
        • Drive Channels
        • Simple Motor iMates
        • Replacing Simple Electronics
        • Completing Half of the Drive
          • Bearing Flats (Best Practice)
          • Wheels
          • Powered Gear
          • Spacer Boxing
          • Spacers, Washers and Standoffs (Best Practice)
        • Model Browser Folders
        • Mirroring (Best Practice)
        • Model Browser Folder (Right)
        • Main Assembly
      • Fusion 360 Chassis
      • Solidworks Chassis, Chain, and Custom Plastic
    • Remembering The Best
      • 62A Skyrise
      • 400X Nothing But Net
      • 2587Z Nothing But Net
      • 365X Starstruck
      • 62A In The Zone
      • 202Z In The Zone
      • 5225A In The Zone
      • 169A Turning Point
      • 929U Turning Point
      • 7K Tower Takeover
      • 5225A Tower Takeover
      • 62A Change Up
    • Scuff Controller
  • 💻Software
    • Odometry
    • Path Planning
    • Robotics Basics
      • Arcade Drive
      • Tank Drive
      • Joystick Deadzones
      • Curvature (Cheesy) Drive
      • Subsystem Toggling
    • Organizing Code
      • Code Style
      • Code Styling Guide
      • Writing Good Comments
      • Version Control
    • Control Algorithms
      • Bang Bang
      • PID Controller
      • Basic Pure Pursuit
      • Flywheel Velocity Control
      • Kalman Filter
      • Take Back Half (TBH) Controller
      • RAMSETE Controller
    • Competition Specific
      • Operator Control
      • Autonomous Control
    • C++ Basics for VEX Robotics
      • Basic Control Flow
      • Enumerations
      • Namespaces (::)
      • Multiple Files (C/C++)
    • VEX Programming Software
      • PROS
        • OkapiLib
      • vexide
      • Robot Mesh Studio (RMS)
      • EasyC
      • RobotC
      • VEXcode
      • Midnight C
    • General
      • Stall Detection
      • Register Programming
      • Sensors and Odometry in Autonomous
      • Embedded Programming Tips
      • Debugging
      • Bit Shift
      • Bit Mask
      • Autoformatting
      • Finite State Machine
      • Data Logging
    • Object Recognition
      • Red Green Buoy
      • AMS
      • OpenCV
      • OpenNI
    • 🤖AI in VRC: Pac-Man Pete
  • ⚡VEX Electronics
    • V5 ESD Protection Board
    • VEX Electronics
      • VEX V5 Brain
        • V5 Electronics Observations and Issues
      • VEX Controller
      • VEXnet and V5 Robot Radio
      • VEX Battery
      • VEX Motors
    • VEX Sensors
      • 3-Pin / ADI Sensors
        • Encoder
        • Potentiometer
        • Limit Switch
        • Bumper Switch
        • Accelerometer
        • Gyroscope
        • Ultrasonic
        • Line Tracker
        • LED Indicator
      • Smart Port Sensors
        • GPS Sensor
        • Rotation Sensor
        • Vision Sensor
        • Optical Sensor
        • Distance Sensor
        • Inertial Sensor (IMU)
        • 3-Wire Expander
    • V5 Brain Wiring Guide
    • Legacy
      • VEX Cortex
      • Power Expander
      • VEX Motor Controller
      • VEX Cortex Wiring Guide
  • General Electronics
    • General Topics
      • External Boards
        • ASUS Tinker Board S
        • Arduino
        • Beagleboard
        • Leaflabs Maple
        • LattePanda
        • Meadow F7 Micro
        • Netduino
        • ODROID-XU4
        • Pandaboard
        • Raspberry Pi
      • Analog-Digital Converter (ADC)
      • Bit-Bang
      • GPIO
      • I2C
      • Jitter
      • Line Noise
      • List of Tools
      • Output Drive
      • Power Consumption
      • Radius Array
      • Resettable Fuse (PTC)
      • SPI
      • Slew Rate
      • Stalling
      • USART
      • UART
      • 5 Volt Tolerant
      • DC Motor Basics
Powered by GitBook
LogoLogo

This work is licensed under a Attribution-ShareAlike 2.0 Generic License

On this page
  • Factors influencing slew rate
  • Applications
  • Teams Contributed to this Article:

Was this helpful?

Edit on GitHub
Export as PDF
  1. General Electronics
  2. General Topics

Slew Rate

Slew rate refers to the maximum rate at which a digital signal (usually a GPIO pin) can flip between its high and low states.

PreviousSPINextStalling

Last updated 4 years ago

Was this helpful?

Diagram showing the difference between an ideal signal (the red waveform) and the actual signal affected by slew rate (green waveform)

Factors influencing slew rate

Slew rate is influenced by two primary factors. When a microcontroller attempts to change the value of a GPIO pin, it switches the pin to either its I/O voltage or 0 V. However, if the current voltage on the pin differs from the new voltage, continuity of charge dictates that the voltage cannot change instantaneously. Rather, the voltage changes through an exponential curve, the rate of change depending on the resistance of the switch (MOSFET) and the capacitance of the output.

Applications

Teams Contributed to this Article:

GPIO pins with high generally have low switch resistances and therefore a faster slew rate. However, the capacitance of the output depends both on the attached load and the parasitic capacitance inside the microcontroller. Load capacitance mainly comes from long wires or high-impedance inputs.

Typical slew rates range from 10 ns to 125 ns. These correspond to maximum signal change rates of 100 MHz and 8 MHz respectively. Generally, communication using a slow protocol such as or has few issues with slew rate, but faster protocols such as USB and may have data corruption if the slew rate is insufficient. Just because a signal can be generated quickly does not mean that the destination can understand it; observe maximum frequency limitations carefully.

The highest slew rates are found among high-speed purpose-built microcontrollers such as the and . A 16 MHz cannot obtain a 100 MHz slew rate, and the very low drive strength of high-speed processors such as the leads to slower slew rates.

(Purdue SIGBots)

Output Drive
UART
I2C
SPI
V5 Brain
Leaflabs Maple
Arduino
Pandaboard
BLRS