Josh Levine writes: It can be nice to know how much battery power you have. It becomes critically important with LiPo batteries since you can permanently damage them by running the voltage down too low. Typically battery voltage detection requires adding a circuit with extra parts and their associated power requirements. Wouldn’t it be great […]
Author Archives: DP
Using the cirrus logic CS5464 for AC current measurement
Using the cirrus logic CS5464 for AC current measurement by Corgi-Tronics: Continuing the series on examining devices to measure AC current, this time we’ll try out the CS5464 from Cirrus Logic. I initially built it up on a breadboard, but I’ll skip writing up this test and instead build up a prototype and run AC line […]
Free PCB coupon via Facebook to 2 random commenters
Every Friday we give away some extra PCBs via Facebook. This post was announced on Facebook, and on Monday we’ll send coupon codes two random commenters. More PCBs via Twitter on Tuesday and the blog every Sunday. Don’t forget there’s free PCBs three times every week: Free PCB Sunday. The classic. Every week, get free […]
Week in (p)review November 07, 2014
Here’s a summary of major developments over the last week. Free PCB Friday is coming up soon. DIRTY TUESDAY: Adventures in SQL with stats and stuff A script to dump an Atmel AT45DB041B 4Mbit SPI Flash part’s contents to disk using a Bus Pirate Bus Pirate v3 and LM75 temperature sensors Coming up: Free PCBs […]
Swimming robotic micro-scallop
Prof. Peer Fischer and his team at Max Planck Institute for Intelligent Systems in Stuttgart, Germany have developed a tiny robotic scallops that can swim through blood and eyeball fluid to fix damaged cells: For years now, scientists have been trying to develop microscopic robots that can swim through bodily fluids and repair damaged cells or deliver medicine. Now, a […]
Simple CMOS FSK modem
Dilshan Jayakody writes: This project is about 4046 PLL base simple FSK modem. Under given configuration this modem send digital signals over two frequencies and which is switching around 378kHz and 226kHz. In this system, modulator uses VCO of 4046, and demodulator is based on close loop mode of 4046 phase comparator and external LPF […]
Get free LinkIt ONE and groves with successful prototype
Seeed Studio is giving away LinkIt ONE. For more details visit Seeed Studio’s blog: LinkIt ONE has been sold out 2,000 + pcs since its launch on Sept.22th . Everything goes perfect except the lack of demo or prototype built in LinkIt ONE, we hope various of funny and practical prototypeswill be born on LinkIt ONE […]
A NPN transistor Electret condenser microphone preamp for microcontrollers
Davide Gironi writes: This is a NPN Electret Condenser Microphone Preamp board design for the use with microcontrollers ADC. In order to make an electret condenser microphone signal “readable” by a microcontroller ADC, it has to be matched the ADC specification of the microcontroller. Most of the time it means, add some gain to the […]
Mooltipass, an open source offline password keeper
Password keeper for all platforms and devices on Indiegogo, the Mooltipass: The Mooltipass is an open source offline password keeper, a project that started a little less than a year ago. Dozens of contributors from all over the globe got together to work on this device that offers significant advantages over closed or software based password […]
Adventures in Moteino: Remote temperature monitor
Colin over at CuPID Controls writes: We want to put our remote sense and control modules out into the wild and read and aggregate them as it makes sense. Our basic system layout is as below. We’ve got multiple wireless nodes that broadcast data periodically, and a controller/aggregator that will log this data, acknowledge […]
Bus Pirate v3 and LM75 temperature sensors
Brixit writes, “This is a tiny reference for reading the temperature with an LM75a temperature sensor and a Bus Pirate v3 on a Linux computer.” Get an assembled Bus Pirate for $30, including world-wide shipping. Also available from our friendly distributors.
PL2303HX userspace GPIO control tool
Necromant writes: This is a small tool for linux userspace that allows you to interact with GPIO lines on PL2303HX devices. It has only been tested on PL2303HXA, but may work for other revisions. Since no common GPIO driver for those exists at the time of writing in the linux kernel – this should serve as […]
EWaste 60$ 3D printer
A DIY 3D Printer built out of reused electronic parts by mikelllc, an instructables here: This project describes the design of a very low budget 3D Printer that is mainly built out of recycled electronic components. The result is a small format printer for less than 100$. First of all, we learn how a generic CNC system works (by […]
#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 […]
8 channel relay board
Rajkumar published another project on Electronics Lab, an 8 channel relay board: 8 Channel Relay Board is a simple and convenient way to interface 8 relays for switching application in your project. Input voltage level support TTL as well as CMOS. Easy interface with Microcontrollers based projects and analog circuits.
LED matrices and MAX7219 ic’s
A 10 60mmx60mm Led matrices controlled by an ATmega328 + 10 MAX7219 ic’s from Bajdi Electronics: Made a big LED matrix this week using 10 60mmx60mm LED matrices. I designed the PCB’s myself and had them made in China. Every PCB has a MAX7219 and a header to plug the LED matrix in. The 10 PCB’s are […]
The smallest thermal imager
A small thermal imaging sensor from Mike’s Electric Stuff: Info on using the Flir Lepton thermal image sensor used in the Flir One Iphone add-on. See videos for more info. Via Hacked Gadgets. Check out the video after the break.
Keithley 197 battery option build
Kerry Wong blogged about his Keithley 197 battery option build: I have been quite happy with my fixed-up Keithley 197 5 ½ digit bench meter purchased from eBay (you can find the teardown pictures here) earlier this year. Keithley 197 has a battery pack option (Model 1978), and this option allows it to run on battery […]
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: Self-starting can be hard to do – Understanding power-on-reset requirements in regulators and bandgaps
Things should be set-up properly before putting all load back again. Here’s a tip(PDF) from MAXIM on self-powering/recovering from power loss. Self-starting is a necessary but sometimes difficult task, whether it is motivating humans, starting cold automobiles, or providing power-on-reset (POR) for ICs. PORs ensure systems start in known and safe states. This app note […]