Sunday, May 17, 2009

Revealing the Ideas behind Circuits

Electronic circuitry is more art than science. Inventing novel electronic circuits is a result of human fantasy, imagination and enthusiasm.

Revealing the Ideas behind Circuits

We treat electronic circuitry not only as a science, but also as an art. Inventing novel electronic circuits is a result of human fantasy, imagination and enthusiasm.

Practical Electronics

Fortunately, abstract electronic circuits are based on clear and simple ideas, which we may derive from our human routine. In order to really understand how circuits operate, we have first to reveal the basic ideas on which they are grounded..."

This book is part of a series on Electric Circuits:

Practical Electronics

The aim of this book is to teach you simple analogue and digital electronics at a practical level. For the in-depth theory of electronics, please read the Electronics Textbook. By the end of this book, you should be able to combine circuit elements to create more complex circuits, and have an understanding of how it works.

Wednesday, May 13, 2009

Electronic Educational Applets - Paul Falstad

"These are some educational java applets I wrote to help visualize various concepts in math, physics, and engineering." - Paul Falstad - (now with HTML5 and Canvas)

Electronic Educational Applets - Paul Falstad
  • Math and Physics Applets - MyPhysicsLab - Physics Simulation with Java.
  • Index of Circuit Examples - Demonstrates various electronic circuits.
  • Digital Filters - Filters digital signals and plays the output on your speakers.
  • Acoustic Interference Applet - Audio interference between your speakers.
  • Waveguide Modes Applet - Electromagnetic waves in a waveguide.
  • Antenna Applet - Generates antenna radiation patterns.
Electronic Educational Applets - Paul Falstad

Analog Circuit Simulator Applet - Demonstrates various electronic circuits.

"This java applet is an electronic circuit simulator.  When the applet starts up you will see an animated schematic of a simple LRC circuit. The green color indicates positive voltage.  The gray color indicates ground.  A red color indicates negative voltage.  The moving yellow dots indicate current."

iCircuit is the easy to use electronic circuit simulator and designer - the perfect tool for students, hobbyists, and engineers.

Its advanced simulation engine can handle both analog and digital circuits and features realtime always-on analysis. It is the perfect companion to students, hobbyists, and engineers.

Learn + Make + Teach Electronics at EveryCircuit

Build any circuit, tap play button, and watch dynamic voltage, current, and charge animations. This gives you insight into circuit operation like no equation does. While simulation is running, adjust circuit parameters with analog knob, and the circuit responds to your actions in real time.

    Friday, May 08, 2009

    Analog Mux for Data Acquisition Systems

    Here is a 4-20 mA In/Out Analog Mux with Cascade option. This is a simple circuit i designed to make a Automation System within a budget.

    Analog Mux using 4051

    This takes 4-20mA from many Transmitters and gives out just one 4-20 mA output. The Mux is done with a digital byte or word. This is a slow scanner as process is slow, that way many analog inputs can be multiplexed and sent into one analog input of a D/A. In near real time systems a faster mux could be used or mux totally avoided. This was made in some numbers, so the pcb is better than others.

    4-20mA Multiplexer Circuit - pdf

    Friday, May 01, 2009

    100kHz Half Bridge Convertor - SG3525

    This is a SMPS Circuit improved over the Application Note in the book SGS Motion Control Application Manual. This worked well. It helps you learn more about High Frequency Power Supply Design.

    Read about SG2525 - SG3525 - PWM SMPS Regulator Chip.

    Some Notes Related to the Project
    • In main circuit do not link different grounds.
    • Main circuit can be used both for 110 AC and 230 AC
    • Ferrites are partial conductors use proper insulation before winding.
    • For main transformer TRX2 use split bobbin for good/safe isolation.
    • Epoxy coated toroids have to be further insulated before winding.
    • Line of isolation between primary and secondary circuits should be explicit.
    • Primary components like Q1, Q2 tabs R5, R6 etc can give shock take caution.
    • Each main module is 500W and can be used in parallel for more current.
    • Q1 and Q2 should have appropriate isolated heatsinks TO220 type 50sq cm
    • Schottky diodes D5, D6 should have heatsinks TO220 type 100sq cm.
    • Diodes D5, D6 eg D83004 are TOP3 packages are used 2 in parallel.
    • For 200W and above R2=0.1e 5W in the main circuit fusible ceramic.
    • C10, C11... Add 4.7uF 100v more in parallel to reduce ripple.
    • C13, C14 can be 250V for better safety margin.
    • TRX1 SEC1 and SEC2 dot polarity is anti-phase if same phase danger!!
    100kHz Half Bridge Convertor - SG3525

    Magnetics Design

    All Transformers Isolation 1kV PRI To SEC / SEC To SEC / PRI,SEC To Core. Use Yellow Mylar Tape Insulation or better for all. Vacuum Impregnate all Magnetics in Epoxy or Varnish. All Power Tracks on PCB reinforce with Copper Braid.

    TRX1 Mosfet Drive Transformer
    T25.0 MGQ-5L Hitachi - Type Torroid - 100khz Signal
    PRI1 20 Turns #22 Awg - SEC1 9 Turns #22 Awg - SEC2 9 Turns #22 Awg
    486T250-3C8 Ferroxcube - SEC1 And SEC2 Antiphase

    TRX2 Stepdown Invertor Transformer
    EC52 Siemens/Hitachi - Can Be ETD/EER Cosmo Ferrites
    PRI1 22 Turns 2 Layers (44 Turns) - 2* #16 Awg(18 Swg) In Parallel.
    SEC1 4 Turns Ct Copper Strap 0.01" * 0.8" Copper Strap
    Coper Strap/Ribbon used, cause Hi-Freq Skin Effects, PRI 2 Wires paralleled for same reason.EC52-3C8 Ferroxcube Phillips

    TRX3 Current Feedback Trx
    T25.0 MGQ-5L Hitachi - Type Torroid - 100khz Signal
    PRI1 1 Turn 4 Amps Max - SEC1 20 Turns #22 Awg CT. - Ceter Tap 10T-CT-10T
    486T250-3C8 Ferroxcube

    L1 Series 60A-80A Inductor
    Type EC/ETD/EER EC42 Hitachi - Air Gap In Inductor Core Both Sides
    100khz Power IF30-3C8 Ferroxcube - 6 Turns 4*#12 AWG In Parallel
    4 Wires Of 12 AWG Twisted & Wound For 6 Turns (Use Less AWG For Less I)

    TRX5 50hz Transformer Small
    PRI1 & PRI2 115v - SEC1 24V 0.2A - JP2 2-3 Short 230V
    PRI1 & PRI2 In Parallel For 110V - JP1 1-2 Short 230V 2-3 Short 110V 

    TRX4 - This is A 10mH Common Mode Filter

    PCB Layout
    The PCB of module will be added later, if i locate it. It is small and be designed easily.


    Basic Electronics
    Basics of Electronics
    Product Production
    Work Discipline
    Testing Points
    Learning Electronics
    Electronics Theory

    Production Notes
    Prototype Fabrication
    Electrical Circuits

    Scots Guide Electronics
    Engineering - Wikibooks
    Design Lab - Jim Svoboda
    DC Circuits UOG
    Socratic Electronics
    Blobz Guide Electric Circuits

    Product Design
    Product Development
    Constant Current Source
    Good Voltage Regulators
    Insulation Resistance
    Digital Insulation Tester
    DN Schematic PCB 04
    DN Product Design 07

    Hobby Circuits
    VU Meter Circuits
    LED brightness control
    555 Incredible Chip
    Process Control
    liquid level measurement
    Thermocouples and RTD
    Design ADC Interface uC
    Thermocouple Amplifier
    IA Instrumentation 02
    Temperature on DMM
    Optical Proximity Switch
    Analog Mux - Data Acquisition

    Test Measurement
    Instrumentation Automation
    NI Test and Measurement
    DMM Digital Multi Meter
    Oscilloscope in T&M
    IA Automation 01
    Build Instruments
    Tektronix T&M Equipment
    Educators Corner – Agilent

    Power Electronics
    UPS Background
    Transformer Connections
    DN Power Electronics 03
    DN Power Electronics 02
    Half Bridge Convertor SG3525

    Interfacing Microcontrollers
    Embedded Process Control
    80C31 8052 Microcontroller
    Microprocessors and uC
    Embedded Systems Design

    Good Voltage Regulators
    Relays and Contactors
    Potentiometers Trimpots
    Prototype Boards Types
    Types of Capacitors
    Types of Switches
    Resistors How they Work
    Coils Transformers SMPS
    Mains Transformers Types
    DN Components Selection 05

    Tutor Gadgets
    Count-Up Timer
    Digital Logic Gates
    Electronics Tutors

    Teaching Instruments
    Charles Proteus Steinmetz
    Muntzing a Circuit Design
    Teralab Electronics projects
    Historical Instruments

    Tables, Charts, Videos
    Binary and Hex
    Resistor Color Code
    Ohms Law
    Giga, Tera, Pico, Nano
    High Resistance Materials

    School - Analog Design
    DN Analog Basics 06
    DN Op-Amps 01
    TI Semiconductors

    Hobby DIY Garage