Top new questions this week:

Sine signal generation using PWM

We are unable to generate a sine signal properly using a MC68HC908GP32 microcontroller. PWM description begins in page 349. Clock frequency is 2.4MHz, while we have used 7 kHz PWM by using the …

microcontroller c pwm

asked by Serge 12 votes answered by Stacey Anne 11 votes

How are electronic circuits implanted on to microprocessors?

For example, there must be some electrical pathways with resistors, capacitors to store energy (bits) in a field, etc. How is this done, and what machine does this? I want to get access to one, …

integrated-circuit

asked by Holly Jona 9 votes answered by Olin Lathrop 40 votes

Why does a simple conductor start to emit EM waves when carrying a signal?

I understand that on circuit board traces with a clock, if the higher harmonics have sufficient power, it results in electromagnetic waves being emitted from the traces which creates EMI. What I don't …

electromagnetism emc interference

asked by quantum231 9 votes answered by Dave Tweed 7 votes

What does the term "bias" mean?

I've see a number of terms that make reference to the word "bias". I've read the wikipedia article but I'm after are more practical answer. Some examples of what a forward or reverse biased device is …

terminology

asked by Brad 9 votes answered by The Photon 9 votes

Why exactly 470 or 1k Ω? (to prevent damage of output pin)

Quote from the Arduino tutorial, section Digital Pins: Short circuits on Arduino pins, or attempting to run high current devices from them, can damage or destroy the output transistors in the …

arduino resistors short-circuit

asked by feklee 9 votes answered by AndrejaKo 13 votes

Do different frequencies have different capabilities?

I read that google was planning on purchasing a spectrum from the Fcc and they were going to use it to transfer data. I was wondering if the value of the frequency affects the data that is being …

bluetooth spectrum

asked by Coder404 7 votes answered by Chris Stratton 11 votes

Where can I send my 0.005% 1 PPM tempco calibration resistors to find out their "true" value?

edit: putting this at the top because people keep answering questions I didn't ask: Where can I get this done cheaply by a place that is hobbyist friendly? I don't even know where to look. I imagine …

resistors calibration

asked by Nick 7 votes answered by DrFriedParts 4 votes

Greatest hits from previous weeks:

What are the differences between a gyroscope, accelerometer and magnetometer?

What is the difference between a 3-axis gyroscope, 3-axis accelerometer and 3-axis magnetometer? How do these sensors work? Why are all 3 used in some devices like smartphones, tablets, quadcopters …

sensor accelerometer gyro imu compass

asked by Kicsi Mano 12 votes answered by drxzcl 19 votes

What sensor to choose to track human presence indoors?

This is a hobby project about home automation. The idea is that of distributed system of cheap microcontrollers that take measurements, communicate, output data and control appliances. One important …

sensor home-automation

asked by Vorac 11 votes answered by Olin Lathrop 4 votes

Can you answer these?

Make an LED Ring Light Up Smoothly?

I am working on a project that would look really cool if I was able to put a ring of LEDs (kind of like the one on the TRON Identity Discs) light up smoothly in a circle, rather than have sections of …

led led-strip

asked by M. Choi 2 votes

Has anyone seen power cycle corruption in industrial SD cards?

I am using a micro SD card in a new embedded Linux system (choice of SD was not mine, was made by the hardware guys). I have seen a problem before where power cycling of a system without doing a …

power-supply linux sd

asked by fred basset 1 vote

TFT LCD interface with a Microcontroller: Getting Started

I have a small 3.5 in TFT LCD display from a Chinese manufacturer. It doesn't have an integrated LCD controller. The documentation claims it is a "16 bit RGB/parallel interface" and it uses a Renesas …

microcontroller lcd tft

asked by Forhad Ahmed 1 vote