Archive for the ‘Arduino’ Category

TASCAM Sound Recorder (Part 4)

Part 1, 2, 3, 4 And here is the driver code. Nothing exceptional just plain good’ol arduino code. Check the writeByte function which contains few tricks and optimizations that are mandatory to achieve a proper timing. Ultimately this code contains a pretty versatile bit-bang UART writer that you may want to reuse in various applications. Enter […]

TASCAM Sound Recorder (Part 3)

Part 1, 2, 3, 4 As per product reviews on the web and as per my personal experience, the DR-40 picks up noises generated by the handling of the device. One way to prevent such noises consists in using a wired remote controller namely the Tascam RC-10. The key component from this option is a […]

FN-M16P MP3 player (Part 1)

Part 1, 2 How come I managed to miss this fancy little module ? It’s my good ol’ friend Sébastien from Quai-Lab who showed me this little piece of electronic which he included in his inMoov robot. Bright idea ! For a few €, his robot will speak and improve its interactions to the public. […]

Particle sensors (Part 1)

Part 1 I am amazed by the massive improvements of sensors along the last 10 years. Not so long ago, some sensors would fit in a shoe box and require 24 VDC, not to talk about the interfaces, weight, etc. These improvements are mainly due to the incorporation of advanced sensors in smart phones: camera, […]

Metal detector (Part 1)

“Dear cousin, I lost my keys in the middle of the meadows, would you please make a metal detector for me ? Urgent !“ This is really how this project started ! More or less, as I have in mind the design of an Earth’s Field Nuclear Magnetic Resonance spectrometer which features magnetic fields sensors on […]

Switch Mode Power Supplies (Part 3)

Part 1, 2, 3 Current sensing. This part is probably the most critical and most uneasy. It is critical because current sensing will protect both the power supply and the driven load from excessive currents and thus excessive amounts of energy dissipated in both the source and the receiver. There are multiple designs available for […]

Direct Digital Synthesizer (DDS) (Part 9)

Part 1, 2, 3, 4, 5, 6, 7, 8, 9 Let’s go a few steps further in the direction of a fully featured arbitrary wave generator ! The early posts describe how to generate clean waves at various frequencies. In this post, I will explain how to offset the signal and how to attenuate it. Setting negative offsets requires… negative voltage ! Which Arduino  platforms do […]

Switch Mode Power Supplies (Part 2)

Part 1, 2, 3 Next picture illustrates the principle of operation of my proposal for an arduino controlled Switch-Mode Power Supply (SMPS): Instead of using an integrated chip, we will use arduino as a controller. The basic configuration requires an output line to drive the switch and two analog inputs for reading the voltage from the current […]

Switch Mode Power Supplies (Part 1)

Part 1, 2, 3 This is the begining of a series of posts dedicated to an original subject that I had in mind for sometimes now. After few attemps, I decided to share my early design which might drive us up to building a versatile lead-acid battery charger. The aim of these posts is not […]

Direct Digital Synthesizer (DDS) (Part 7)

Part 1, 2, 3, 4, 5, 6, 7, 8, 9 A recent project lead me to excavate a quite old DDS design which may be of some interest for you. Instead of using a ladder of resistors, this design features a simple, cheap and yet powerful digital to analog converter. I will later explain why I choose this particular Microchip circuit but for […]