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Electric double layer capacitor an eFlywheel

The Electric double layer capacitor has the main use of a Charge Reservoir. That means a large amount of electrical charge in a small footprint.

These charge/discharge quickly unlike the battery, There is no Electrical Energy to Chemical Energy Transformation and back, like in batteries. It may need caution in design and usage as they may [...]

Design Notes – Components Selection – 05

Selecting the parts for your product design, choosing the components intelligently is a part of Product Design Engineering.

Budget, Availability, Size, Alternate Vendors, Product Life and Quantity to be manufactured are some factors that determine the selection of a prudent and experienced design professional.

To choose the right type of part, an exhuastive knowledge of the behaviour [...]

Circuits using only discrete devices

Here are circuits made of Resistors, Capacitors and Inductors which are passive components. Crystals, Thermistors, Varistors, Variable Passive RLC are also Passive Parts. Zeners, Diodes, NPN-PNP Transistors, FET, MOSFET, SCR, Triacs are all discrete active devices.

Circuits using only discrete devices

Isolated dual power supply from 5V
Telephone LED status indicator
Music Sound to light converter
Simple Water operated relay
LED [...]

Potentiometers and Trimpots

20 Turn Bourns
Single Turn Wire-Wound
Single Turn Film
10 turn Spectrol

Precision, Linear Temperature Stability Instrumentation Many Operations Panel Control Encoders
Panel Control 1 Watt Wire Wound Temperature Stable Blind Timer Thermostat
Panel Control Volume Control Motor Control Low Cost Low Power Log and Linear
Precision, Linear Temperature Stability Instrumentation Many Operations Panel [...]

Resistors and How they Work

1/4W Metal Resistors
Riedon MFR
Resistor Networks
Audio Gold
LVC Ser

Futurlec
Riedon
Caddock
Ohmite
Ohmite

1/4W Metal Film Resistors. High stability Solid construction 1% tolerance 1R to 10M
1 Ohm to 10 Meg Ohm Tolerance to ± 0.05% Low Temp. Coeff. TC ± 3ppm/°C Very Low Inductance Matched Sets too
39 standard models Type 1776 precision networks Absolute Tolerance Absolute T-Coef
3 watt to 50 [...]

Coils and Transformers for SMPS

Coil Winding Specialist
Coil Winding Specialist
Coil Winding Specialist
Coilcraft
Coilcraft

Toroid Inductors
Axial-Radial Coils

EE Core Transformers

Pot Core Trx
Drum Core Coil

High Q Low Cost Difficult to Wind Easy To Mount
Very Low Cost Low Q RF Radiation Easy to Wind
High Power and Q More Pins, Robust Air Gap Adjust Split Bobbin Too
Shielded Adjustable High [...]

Principles of Semiconductor Devices

Principles of Semiconductor Devices

The purpose of this text is to explore the internal behavior of semiconductor devices, so that we can understand the relation between the device geometry and material parameters on one hand and the resulting electrical characteristics on the other hand.

Schottky diode current
Metal-Semiconductor contacts
Electrostatic analysis of a p-n diode
Reverse bias breakdown
Optoelectronic devices
Light Emitting [...]