Electronics in the Age Of The Arduino

Status

A workshop that SCIL is thinking about offering.

General

Electronics has changed in the age of the Arduino, not just because of the Arduino but other things have also contributed:

• Most electronics now have micro controllers and software
• While discrete components still exist much work is done with sub assemblies often containing 100's of components.
• Prices have fallen.
• The web provides almost real time access to components and other gear.
• Specifications that used to require ownership of manuals are now online.
• Tons of learning material online.

This course will help you navigate this new landscape.

More info? contact: User:Russ_hensel

Theory

Then

In the old days electronics was taught from a theory of basic components:

• Batteries - source of dc voltage
• Resistors
• Series and Parallel Circuit.
• Network theory
• Current
• Capicators
• Inductors
• Transistor
• ......
• Complex circuits
• AC theory.....

How To Build An Amplifier

• Find plans or design a power supply
• Find plans or design an amplifier
• Make parts list and order.
• Build and debug.
• Tens of parts.

Now

Now you still need to know the basics of Voltage, Current, and Power, this is perhaps best understood by using the analogy of electricity to water and water pressure: ( link needed ). Rather than think of AC and DC it is probably best to think of these as quantiles variables that change with time. DC is just a Voltage that is constant, and therefore the simplest, to understand.

Next think of other circuit components as "black boxes" that have some practical use, and for now ignore how they work. The old basic components: Batteries, Resistors, Capacitors, Inductors, Transistor.... are just examples of these black boxes, but perhaps not the place to start as you can easily buy much more interesting ones for cheap money.

In the new world we need to think of the power/load characteristics of "the black boxes" and the communications between "black boxes".

How To Build An Amplifier

• Order an amplifier and power supply ( must know how to select appropriate parts )
• Connect amplifier to power supply
• Two parts plus wire.

Spend Time On

• Basic concepts of Potential Difference ( Voltage units Volt ), Current ( units Ampere ), Power ( units Watts ) Charge ( units Coulomb ) Time ( units second )
• Basic ohms law, but note that it is not a law for many components, perhaps most. Is good for metal like wires and resistors.

Spend Less Time On

• Series/Parallel Circuits - except to know in series circuits the current is identical for all components, in parllel circits the voltage is the same for all components.
• Resistor Code - skip it use a meter.
• AC Impedance Calculations

Theory Details - Things to Learn

Power/Load

Electrical energy is typically used in 2 way: to carry data ( wifi, telephone, sensor readings.... ) and to carry energy = power * time. Even when used to carry data there must be some power/energy used. The term load is used when device A which has a power source is connected to device B which uses some of that energy. Device B is the load ( what is being "carried" ). When connecting device B the load we want to make sure we do not over load device A. If we want a battery to last a long time we want as "light" a load as possible. The amount of load may be measured by treating it as a resistor or other component, or by specifying its voltage/current characteristics, or by specifying the power it draws form the source.

Constant Voltage

Most circuits are set up as constant voltage. By that we mean that for some time the circuit operates with some voltage constant. Here we will consider it constant even if it is constant for a short time as with a pulse, which while varying is constant first at one voltage and then at another.

Output

A simple constant voltage output might be a simple battery, say a 9V battery. It is called a 9V battery because under reasonable load for a reasonable time the voltage is 9V. When we connect it to some other component ( called the load ) current starts to flow. This requires that power from the battery be transfered to the load ( power = voltage * current ). We can measure how "heavy" the load is based either on the current or the power. What is a reasonable load depends on how long we want the battery to last. So for a battery a reasonable question is what is a reasonable load ( we will not answer this here ).

Communications

Parts of circuits communicate with each other. In the old days this was mostly by sending a voltage from one part to another. Now we still mostly use voltage but it is coded. Signals typically depend on time so over time the signal changes.

Analog

The signal to be sent typically is just a voltage and the amount of voltage is the signal. For example a temperature sensor might convert the temperature to a voltage proportional to the temperature. We still use this method.

Digital

Here the ......