Here is an up-down counter based on PIC16F88 and 7-segment display. The counter is using SMD components and features a RS-232 interface. This is a simple digital counter with a serial rs-232 and a 7 segment display, i started this project to count items on some shelfs, but it can be...

Reno Rossetti & Inyong Kim discuss about the power needs on portable devices and help us choose the right regulator. A popular power source for portable devices is a single lithium-ion cell with 4.2V at full charge and 2.8V at end of discharge. However, some functions within...

Linear Technology Corporation introduces the LTC7813, a dual output (boost + buck), low quiescent current synchronous DC/DC controller. When cascaded, its independent step-up (boost) and step-down (buck) controllers regulate the output voltage from an input voltage that can be above,...

Fabio Bergamin @ phys.org writes about PULPino which is an open source processor to be used on wearables and IoT. In future, it will be easier and cheaper for developers at universities and SMEs to build wearable microelectronic devices and chips for the internet of things, thanks...

Andy published his accurate and open source frequency counter that uses an Android phone as a display. It’s based on a high accuracy temperature compensated crystal oscillator (TCXO) fed into a phase locked loop (PLL) to create a high frequency reference clock. The reference clock...

This is a small hot-plate for SMT reflow soldering build upon an Arduino Pro and controlled using PWM and high side power MOSFETs. Black Mesa Labs has been using a $20 hot plate for a year now for soldering QFN ICs to PCBs. Only issue so far has been the size ( 10″x10″x3″ ) and...

VoCore is an open source hardware that runs OpenWRT Linux. This tiny computer comes with Wi-Fi, USB, 20+ GPIOs that will help you to embed it on your projects. With each passing day, mini computer boards are getting more and more popular. Single board computers like Raspberry Pi,...

Bob tipped us with his latest project, it's a 9V to 1kV DC-DC converter using CD4011 IC to produce a square wave and a IRF530 transistor to drive the transformer. Finally, I have made a new high voltage supply based on an inverter transformer and voltage doubler. It seems to be ok...