Inst ToolsInst ToolsInst Tools
  • Ask
  • Courses
  • Videos
  • Q & A
    • Interview
      • Instrumentation
      • Electronics
      • Electrical
      • Practical Questions
    • MCQ
      • Instrumentation MCQ
      • Electrical MCQ
      • Electronics MCQ
      • Control Systems MCQ
      • Analog Electronics MCQ
      • Digital Electronics MCQ
      • Power Electronics MCQ
      • Microprocessor MCQ
      • Multiple Choice Questions
  • EE
    • Electronics
      • Electronics Q & A
      • Electronic Basics
      • Electronic Devices & Circuits
      • Electronics Animation
      • Digital Electronics
    • Electrical
      • Electrical Basics
      • Electrical Q & A
      • Power Electronics
      • Electrical Machines
      • Electrical Animation
      • Power Systems
      • Switchgear & Protection
      • Transmission & Distribution
  • Measure
    • Control Valves
    • Calibration
    • Temperature
    • Pressure
    • Flow
    • Level
    • Analyzers
    • Switches
    • Vibration
    • Solenoid Valve
  • Control
    • PLC Tutorials
    • Control Systems
    • Safety Instrumented System (SIS)
    • Communication
    • Fire & Gas System
  • More
    • Design
    • Tools
    • Animation
    • Basics
    • Formulas
    • Standards
    • TextBooks
    • Common
    • Software
    • Excel Tools
    • Erection & Commissioning
    • Process Fundamentals
    • Videos
    • Books
Search
All rights reserved. Reproduction in whole or in part without written permission is prohibited.
Reading: Difference between ideal diode & conventional diode
Share
Notification Show More
Font ResizerAa
Inst ToolsInst Tools
Font ResizerAa
  • Courses
  • PLC Tutorials
  • Control Systems
Search
  • Ask
  • Courses
  • Videos
  • Q & A
    • Interview
    • MCQ
  • EE
    • Electronics
    • Electrical
  • Measure
    • Control Valves
    • Calibration
    • Temperature
    • Pressure
    • Flow
    • Level
    • Analyzers
    • Switches
    • Vibration
    • Solenoid Valve
  • Control
    • PLC Tutorials
    • Control Systems
    • Safety Instrumented System (SIS)
    • Communication
    • Fire & Gas System
  • More
    • Design
    • Tools
    • Animation
    • Basics
    • Formulas
    • Standards
    • TextBooks
    • Common
    • Software
    • Excel Tools
    • Erection & Commissioning
    • Process Fundamentals
    • Videos
    • Books
Follow US
All rights reserved. Reproduction in whole or in part without written permission is prohibited.
Inst Tools > Blog > Electronic Devices & Circuits > Difference between ideal diode & conventional diode

Difference between ideal diode & conventional diode

Last updated: October 4, 2016 9:36 am
Editorial Staff
Electronic Devices & Circuits
No Comments
Share
5 Min Read
SHARE

An ideal diode is a diode that acts like a perfect conductor when voltage is applied forward biased and like a perfect insulator when voltage is applied reverse biased.

So when positive voltage is applied across the anode to the cathode, the diode conducts forward current instantly. When voltage is applied in reverse, the diode conducts no current at all.

Ideal Diode Characteristics Curve

Ideal Diode Characteristics Curve

 

You can see that when the diode receives forward voltage, it instantly conducts an infinite amount of current which it can supply to a circuit. When reverse voltage is fed to the diode, it conducts no current at all, no matter how great this reverse voltage is.

These, again, are ideal circumstances. Diodes actually do not act like this.

The I-V characteristics curve of a conventional diode would look like this:

Conventional Diode Characteristics Curve

Conventional Diode Characteristics Curve

 

Below table shows Ideal Diode Vs Conventional Diode

Characteristics Ideal Diode Coventional Diode
Threshold Voltage Ideal diodes do not have a threshold voltage. Once any forward voltage is applied across the diode, it will conduct current instantly across its junctions. Conventional diodes do have a threshold voltage. This is the voltage which must be supplied to the diode for it to conduct any considerable forward current. For silicon diodes, the threshold voltage is approximately 0.7V. For germanium diodes, it is approximately 0.3V. This voltage is needed
so that the electrons of the n junction can have enough push to break the barrier in between and cross over into the p junction. This is how current flows in a diode. Any voltage below the threshold voltage will not be sufficient to push the electrons through from one barrier to the next. You can see this marked on the diode characteristics curve. Before the threshold point, very little current flows across the diode. However,
after the diode receives a voltage above this, it produces considerable current flow.
Forward Current Ideal diodes have infinite forward current when any forward voltage is applied across their terminals. This is because in the ideal condition, the internal resistance of the diode would be 0. The diode would have no internal resistance at all. Since current, I=V/R, an infinite amount of current would be conducted and supplied to a circuit with an ideal diode. Conventional diodes conduct a large current when forward voltage above its threshold voltage is supplied to the diode, but it is still a finite amount of current. Conventional diodes, even though small, still have internal resistance. It is impossible to create any physical component that does not have some internal resistance. The resistance ensures that the current will be finite in nature and cannot be infinite.
Breakdown Voltage Ideal diodes do not have a breakdown voltage. This is because ideal diodes have infinite resistance to reverse voltage. It will not conduct any current at all when voltage is applied in reverse, no matter how great the voltage is. Conventional diodes do have a breakdown voltage. This is the reverse voltage that when applied to the diode will cause the diode junctions to break down and conduct a large amount of current, even though the voltage is applied with incorrect polarity. A diode should not conduct current when voltage is applied the wrong way. However, after a certain point, called the breakdown point, it will give way and conduct.
Reverse (leakage) Current Since an ideal diode does not have a breakdown point,  it never conducts any reverse current, called leakage current. It is a perfect insulator when voltage is applied in reverse. A conventional diode will conduct some leakage current even when reverse voltage is applied, even when the reverse voltage hasn’t reach the breakdown point. After the breakdown voltage is reached, it will conduct a large amount of current, called avalanche current, in reverse. This is because a conventional diode can never be a perfect insulator and will give way if enough reverse voltage is supplied to it.
Don't Miss Our Updates
Be the first to get exclusive content straight to your email.
We promise not to spam you. You can unsubscribe at any time.
Invalid email address
You've successfully subscribed !
Forward Bias & Reverse Bias of a Diode
Circuit Elements and Types of Circuits
Capacitor Filter Working Principle
Half Wave Rectifier Principle
PIN Diode Working Principle
Share This Article
Facebook Whatsapp Whatsapp LinkedIn Copy Link
Share
Leave a Comment

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Stay Connected

128.3kFollowersLike
69.1kFollowersFollow
208kSubscribersSubscribe
38kFollowersFollow

Categories

Recent Comments

  • Guifty Shimica on Top Non-PLC Certification Courses for Automation Professionals
  • Guifty Shimica on Top Non-PLC Certification Courses for Automation Professionals
  • MIHARITSOA Aina Sitraka on Top Non-PLC Certification Courses for Automation Professionals
  • Vaishnavi on Free Instrumentation Course for Trainee Engineers

Related Articles

Zener Diode

Zener Diode Breakdown Characteristics

Optoisolator Working Principle

Optoisolator Working Principle

example-of-KCL

What is Kirchhoff’s Current Law

seven-segment-display-circuit

Seven Segment Display Working Principle

Diode-positive-limiter

Positive & Negative Diode Clippers

Types-of-diodes

Different Types of Diodes

pi filter Operation

pi filter Operation

Short Notes on Rectifiers & Filters

Short Notes on Rectifiers & Filters

More Articles

Hydrostatic pressure Measurement

Basics of Hydrostatic Level Measurement

Single Line Diagram of UPS System

UPS Selection Factors for a Control System

4-20mA Transmitters Easy Calculations

4-20mA Transmitters Calculations

Field Instruments Questions and Answers

Control Room and Field Instruments Questions and Answers

Why is White Powder Used in Electrical Cables

Why is White Powder Used in Electrical Cables?

Reciprocating Piston Meters

Overview of Positive Displacement Flow Meters

Tilt Level Switch Theory

Tilt Level Switch Working Principle

Parallel RLC Circuit

Resonance, Resonant Frequency, Series and Parallel Resonance

Follow US
All rights reserved. Reproduction in whole or in part without written permission is prohibited.
Welcome Back!

Sign in to your account

Username or Email Address
Password

Lost your password?