Electronics Design 101

Electronics Design 101

Jeff Duval and Palash Nandy

Electronics Fundamentals

Get the Electronics 101 slides

Read Sparkfun’s electronics fundamentals

Here is what we are going to go over:

At the end of this you should be able to design the circuit needed for homework

More stuff:

The slides also cover op-amps and power electronics. Very useful for the outputs week

This book: Horowitz and Hill, is the bible for electronics.

PCB Design

Get EAGLE CAD (sparkfun’s setup instruction)

Read Sparkfun’s PCB Basics and How to Read a Schematic

We will cover with a live demo:

At the end of this part you should be able to create a millable file for your circuit

First time:

Each time:

More stuff:

See Jeff’s tutorial for more pointers

FAQ:

Q:Does the voltage divider (with two resistors) always provide the same voltage drop, regardless of the load/resistance on V_OUT? I suppose not, so how do we regulate this?

A 1):No. The rule of thumb here is to load the circuit with 10-20x more resistance. If you make your divider with 10k & 10k you shouldn't connect it to a load lower than say 100k.

A 2):Please note that even 10k & 10k is high for an ADC input. A cheap & simple trick is to place a small (say 10 or 100nF) cap in // with the lower resistor.

A 3):To keep this voltage independent of the load use a follower opamp

Q:Do we need 1 resistor per LED in parallel because otherwise, the current flow will be much higher in some LEDs than others (due to manufacturing variances, etc)? Or for some other reason?

A 1):Yes. If you look at the Current/Voltage curve of a diode (http://www.amperor.com/products/led/images/led_i_v_curve.jpg) you'll see that a slight voltage difference can create a huge difference in current.

A 2):What will happen if you // LEDs with only 1 resistor is that you'll destroy the one with the lowest voltage... then the second lowest... up to the point where they'll all be dead