MMA8453Q is a rather inexpensive accelerometer. It is significantly cheaper than many other 3-axis accelerometers (such as the popular LIS3LV02DL) and yet it offers a reasonably high 10 bits resolution and packs a rich set of features that simplifies designs…
I built a 4-digit 7 segment display last year. In that design, I used four 74HC595 shift registers to drive the four individual 7 segment displays, with one for each digit. So when I wanted to build an 8-digit display,…
Modified sine wave is essentially just a pulse width modified square wave. It is a very useful waveform for power inverters. Compared with the simplest inverters with square waveform, inverters using modified sine wave can compensate the output voltage by…
I have been thinking about building an LC meter for a while since I do not have a multimeter that is capable of measuring inductance and while the multimeters I have can measure capacitance, they are not able to give…
ATmega328p does not provide any Digital/Analog conversion channels (although the D/A conversion can be simulated by means of measuring the PWM output). We can easily add up to eight D/A channels using either a LTC1665 (8 bit) or LTC1660 (10…
In my last post, I described in detail how to hand solder LIS3LV02DL, an LGA packaged accelerometer chip. And here I will show you how the communication with Arduino is done using SPI.
I was inspired by Paul’s 7 segment display and decided to build one myself. He used 4 common cathode 7 segment displays. In his original schematics, all the segments within a display shared one current limiting resistor which unfortunately affect…
I have been using the FTDI bitbang method piloted by Kimio Kosaka and improved by others (1,2,3) to flash Arduino bootloader onto blank ATMega328p for a while and thought I would share my experience with everyone.
H-bridge is frequently used to control DC motors and stepper motors. When controlling a bipolar stepper motor, two full H-bridges are needed. There are many H-bridge ICs (like L298, MPC17529 and SN754410 which is a quad half H-bridge) for just…
After going through some of the tutorials on Arduino’s site, I really started to appreciate what a powerful platform Arduino really is. A lot of seemingly complex software/hardware interactions can be made quite easy with relatively few components and little…
When I first started interfacing electronics with computers back in the early 90’s my hardware choice was an ISA AD/DA card. So when I wanted to experiment with some physical computing stuff recently, I thought of getting an AD/DA card…