Electronics Diodes - denethor.wlu.cadenethor.wlu.ca/pc320/lectures/diodebeam.pdf · Terry...

DiodesZener diodes

ElectronicsDiodes

Terry Sturtevant

Wilfrid Laurier University

September 9, 2015

Terry Sturtevant Electronics Diodes

DiodesZener diodes LEDs

Diodean electronic device which passes current in one direction only

diode starts to allow current in the forward direction when thevoltage reaches around 0.6VIf the voltage gets high enough in the reverse direction, thediode will conduct; “reverse breakdown voltage”

Diodean electronic device which passes current in one direction onlydiode starts to allow current in the forward direction when thevoltage reaches around 0.6V

If the voltage gets high enough in the reverse direction, thediode will conduct; “reverse breakdown voltage”

Diodean electronic device which passes current in one direction onlydiode starts to allow current in the forward direction when thevoltage reaches around 0.6VIf the voltage gets high enough in the reverse direction, thediode will conduct; “reverse breakdown voltage”

Negative pressure; no flow possible

��

No pressure; resistance to flow is large

Small pressure; resistance to flow decreases

Medium pressure; resistance to flow still decreasing

High pressure; resistance to flow small

Very high pressure; resistance almost zero

Diode symbol and physical appearance

anode cathode

Signal diodes (one type)

Signal diodes (another type)

Power diodes (one type)

Power diodes (another type)

“off”

V . 0.7?

“off”

I small; changes slowly

“off”

V ≈ 0.7

6 “on”

I large; almost independent of V

forward biasreversebreakdown

|V | < Vz

I small; changes slowly

forward biasreversebreakdown

I large; almost independent of V

VD ≈ 0.7

Vo ≈ Vs − 0.7(assuming Vs & 0.7)

Forward biased diode in a voltage divider

VD ≈ 0.7

Vo ≈ 0.7(assuming Vs & 0.7)

Forward biased diode in a voltage divider

Vo ≈ Vs(assuming Vs > 0)

I ≈ 0

Reverse biased diode in a voltage divider

Vo ≈ 0(assuming Vs > 0)

I ≈ 0

Reverse biased diode in a voltage divider

One common use of diodes is for rectification, by putting diodesin a bridge circuit.

Here’s the basic bridge.

The output is taken between A and B.

For one half of the cycle, these two diodes shown in green are forwardbiased, so they’re on. (The others are off.)

For the other half of the cycle, the other two diodes shown in greenare forward biased, so they’re on. (The others are off.)

For both parts of the cycle, A is positive relative to B.

LEDs are a special case; they light up above a certain voltage. Thevoltage depends on the colour.

anode (+) cathode (-)

The LED lights up when current flows from the anode to thecathode..

You must use a resistor to limit the current.

You must use a resistor to limit the current.Without a resistor, the LED will probably be destroyed.

The resistor can go before or after the LED.

Reverse-biased, the LED won’t light up.

DiodesZener diodes Parameters

Zener diodes

One of the ways to produce a stable reference voltage, such as foran ADC or a DAC, is to use a Zener diode.

Zener diodes

Parameters

Zener voltagerequired currenttemperature sensitivityvariation with current (ac resistance)

Parameters

Zener voltage

required currenttemperature sensitivityvariation with current (ac resistance)

Parameters

Zener voltagerequired current

temperature sensitivityvariation with current (ac resistance)

Parameters

Zener voltagerequired currenttemperature sensitivity

variation with current (ac resistance)

Parameters

Zener voltagerequired currenttemperature sensitivityvariation with current (ac resistance)

Electronics Diodes - denethor.wlu.cadenethor.wlu.ca/pc320/lectures/diodebeam.pdf · Terry...

Documents

AGS-Electronics Diodes Brochure for diodes… · AGS-Electronics Diodes Brochure PRODUCT NAME TYPE/MODEL ... ULTRAFAST RECTIFIER DIODE 1A 3A UF4001 TO UF4007 UF5400 TO UF5408 (DO-41

TVS Diode Arrays (SPA Diodes) - littelfuse.com/media/electronics/product...1 TVS Diode Arrays (SPA®Diodes) New Product Introduction Feb. 2017

Electronics- Block Diagramsdenethor.wlu.ca/pc320/lectures/blockbeam.pdf · Electronics Block Diagrams Terry Sturtevant Wilfrid Laurier University February 13, 2019 Terry Sturtevant

Electronics- Internal resistance of a voltage sourcedenethor.wlu.ca/pc320/lectures/intresbeam.pdf · Internal resistance of a voltage source Theory Example Internal resistance of

Basic Electronics: Diodes and Transistors ME 435

Electronics- Pulse Width Modulation Sensorsdenethor.wlu.ca/pc320/lectures/pwmbeam.pdf · Terry Sturtevant Electronics Pulse Width Modulation Sensors. Pulse Width Modulation Sensors

Electronics- Operational Amplifier Dynamic Characteristicsdenethor.wlu.ca/pc320/lectures/dynopbeam.pdf · 2015-10-09 · Operational Ampliﬁer Frequency Response Active Filters Slew

Electronics- Logic Gates: Measuring Current Limitsdenethor.wlu.ca/pc320/lectures/lgccurmbeam.pdf · Logic Gates: Measuring Current Limits Terry Sturtevant Wilfrid Laurier University

Electronics Kirchhoﬀ’s Law Exampledenethor.wlu.ca/pc320/lectures/kirchex.pdfTerry Sturtevant Electronics Kirchhoﬀ’s Law Example Introduction Step by step Overview If a solution

Electronics- MCP 3008 Communicationdenethor.wlu.ca/pc320/lectures/mcp3008beam.pdf · MCP Communication (8+adc channel)

Electronics- Signal Conditioningdenethor.wlu.ca/pc320/lectures/sigbeam.pdf · Analog Signal Conditioning Digital Either Interface Types of Signal Conditioning Signal conditioning

Semiconductor Diodes - Electronics · Semiconductor Diodes Module 2.0 Diodes Introduction Diodes are one of the simplest, but most useful of all semiconductor devices. Many types

Robotics Academy Electronics. Introduction to electronics Resistors Capacitors Semiconductors (Diodes, LED, Transistors, IC’s ) LDR Photo(cell, transistor,

Electronics- Resistive Sensorsdenethor.wlu.ca/pc320/lectures/rsensebeam.pdf · Sensors Resistive sensors Resistive sensors in voltage dividers Resistive sensors A resistive sensor

Electronics- Serial Communication-I2Cdenethor.wlu.ca/pc320/lectures/i2cbeam.pdfRaspberry Pi Python I2C Library Serial Communication -I2C Inter-Integrated Circuit Interface Master/slave

Electronics Operational Amplifier Basicsdenethor.wlu.ca/pc320/lectures/opampbasicbeam.pdfIdeal Operational Amplifiers Analyzing Op Amp Circuits Common Operational Amplifier Circuits

Electronics- Interrupts and Threadingdenethor.wlu.ca/pc320/lectures/interruptbeam.pdf · Interrupts allow the event to be detected by built-in hardware, and redirects program control

Electronics- Zener Diodes and Photodiodesdenethor.wlu.ca/pc320/lectures/zenbeam.pdf · 2017-09-26 · Diodes Zener diodes Photodiodes Optical Isolation Basic Diode Operation Application:

Electronics- Logic Gates: Tri-State Outputdenethor.wlu.ca/pc320/lectures/lgctsbeam.pdfElectronics Logic Gates: Tri-State Output Terry Sturtevant Wilfrid Laurier University June 1,

Diodes-Transistors03 - Cal-Chip Electronics