Mare writes: This is another small module to measure air pressure, temperature and humidity. Two sensors are on-board: MS5637 and HDC1080. Microcontroller is small cortex M0 in TSSOP-20 housing from STM: STM32F070CxP. The SN65HVD72DGKR provides RS485 interface functionality with half duplex mode. Voltage regulator, reverse polarity protection and some LED indicators are provided on-board. Complete […]
Author Archives: DP
OpenPnP build
Tom Keddie posted a video showing his OpenPnP pick and place build.
Jumping robot leg
Ben Katz documented his robotic leg project: Here are the python scripts that send serial commands to the motor controllers. Here are the eagle files, gerbers, and BOM for the motor controllers and sensor boards. When I sent the boards to 3PCB, the text the motor controllers got all scrambled so keep that in mind. […]
Homemade EDM (electric discharge machining) machine
In this video Scorchworks demonstrates his DIY EDM (electric discharge machining) machine : My homemade plunge EDM (electric discharge machining) machine built based on the book “Build an EDM” by Robert Langolois. The book consists of a series of articles that originally appeared in The Home Shop Machinist. I deviated from the book in a couple […]
ESP8266 RGB color picker
Rui Santos has released a new project called ‘ESP8266 RGB Color Picker’. He writes: In this project, you’re going to build a web server with an ESP8266 to remotely control an RGB LED. This project is called ESP8266 RGB Color Picker. Full details at Random Nerd Tutorials site. Check the video after the break.
App note: Alkaline battery low-voltage indicator
Battery low-voltage indicator made from two new comparators TSM9118 and TMS9119 from Silicon Labs. Link here (PDF) In many battery-powered systems, a user would like to know when it is time to replace the batteries before they are completely discharged, causing the device being powered to fail completely. Alkaline batteries have an open cell voltage […]
Free PCB Sunday: Pick your PCB
We go through a lot of prototype PCBs, and end up with lots of extras that we’ll never use. Every Sunday we give away a few PCBs from one of our past or future projects, or a related prototype. Our PCBs are made through Seeed Studio’s Fusion board service. This week two random commenters will […]
App note: A practical look at current ratings
An app note from Alpha & Omega Semiconductors about proper way of evaluating MOSFET’s power handling capability based on how much loss it will generate based on the application conditions. Link here (PDF) System designers are often faced with the task of selecting the most suitable power device from a wide array of products from […]
App note: Precision temperature-sensing with RTD circuits
Precision temperature-sensing with RTD circuits application note (PDF!) from Microchip This application note focuses on circuit solutions that use platinum RTDs in their design (see Figure 1). The linearity of the RTD will be presented along with standard formulas that can be used to improve the off-theshelf linearity of the element. For additional information concerning […]
App note: A survey of common-mode noise
A survey of common-mode noise application note (PDF!) from Texas Instruments: This application report provides the results of research regarding common mode noise induced on cables of varying lengths in different environments. It also provides information on noise sources.
GPRS module with M590 for SMS projects
From the comments on our earlier Neoway M590 GPRS tutorial post, the GPRS module with M590 for SMS projects by Nicu: In 1st part I present you few data about GPRS module with M590 chip and how send SMS from them. In 2rd part I send SMS from phone and SMS is received by GPRS module with […]
Neoway M590 GPRS tutorial: sending and receiving files from/to SD card
Neoway M590 GPRS tutorial on sending and receiving files from/to SD card from Vadim Panov: Here’s a bit of useful info from what I’ve been doing lately. I got a job to design a device that connects to a web-server via GPRS and downloads a bunch of tiny WAV files, that it later plays on […]
Running NodeMCU on a battery: ESP8266 low power consumption revisited
Tinkermax shows us how he reduce the current consumption of his v2 NodeMCU in deep sleep to < 50μA: Unfortunately, with all this added convenience comes the drawback of added power consumption, which continues even when the ESP8266 is in deep sleep. I measured 18mA to the NodeMCU board while the ESP8266 was in deep […]
Chrome Apps and serial port communication
Luca Dentella writes, “When it comes to develop a GUI for your project, you may need to be sure it will be available for users under Windows, Linux and MacOS. Chrome Apps may be the solution: they are developed using the same technologies behind any websites (HTML5, CSS, javascript) but, thanks to the Chrome APIs, […]
Amazon’s cheapest multimeter teardown: The DT-830B
A teardown of Amazon’s cheapest multimeter the DT-830B by Electronupdate: Purchased the cheapest multimeter I could find so I could extract the integrated circuit. A surprisingly simple IC! The actual meter design was much as expected. Poor attention to detail for higher voltages, concerning lack of fuses on current measurements… pretty thin feeling probe set. […]
#FreePCB via Twitter to 2 random RTs
Every Tuesday we give away two coupons for the free PCB drawer via Twitter. This post was announced on Twitter, and in 24 hours we’ll send coupon codes to two random retweeters. Don’t forget there’s free PCBs three times a every week: Hate Twitter and Facebook? Free PCB Sunday is the classic PCB giveaway. Catch […]
Remote controlled beer crate
Niklas Roy blogged about his DIY remote controlled beer crate: The “remote controlled beer crate” is actually just a flat plywood platform on which standard sized beer crates can be placed. It is driven and steered by two windscreen wiper motors with direct attached casters. Two swivel casters in front stabilize the construction. On its back, […]
3D Printer extruder review
Bajdi wrote up a review of 3D Printer extruder: End of last year I decided to build a new 3D printer. At that time I already owned a very cheap Chinese Prusa I3 printer, it worked, but wasn’t a very reliable machine and it was dead slow. As I did not want to reuse any of […]
Cherry MX keypad
Dan Watson documented on his blog an open source Arduino-compatible Cherry MX keypad he designed using the ATmega32U4 microcontroller: The board that I designed includes four Cherry MX keys. I used MX Blues, but it is also compatible with other types such as Brown and Red. It’s simply a matter of soldering on the ones […]
ESP8266: SSD1306 OLED library release
Daniel Eichhorn writes: The “ESP8266 OLED SSD1306″ is an open source library which allows you to control those pretty OLED modules from our beloved ESP8266 module. Fabrice Weinberg cleaned up all the ugly pieces of code which I initially wrote caused by my near C/C++ illiteracy. He also added support for Pasko’s BRZO I2C library […]