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 […]
Author Archives: DP
Ultrasonic Anemometer
Lukas Fassler has designed and built an Ultrasonic Anemometer project with Dirty Board PCBs. Full details at Soldernerd homepage.
New ESP8266 board
M0xpd writes: You can well see it is an engineering sample, because I’m squeezing the wrong size packages into locations (quarter Watt resistors where eighth Watt components should be, etc) and using a mishmash of different component types, but you’ll forgive me, I’m sure. The new design presents the Expressif ESP8266 device on an Arduino-sized […]
App note: Class D audio amplifier basics
Class D audio amplifier an efficient amplifier by Infineon Technologies, Link here A Class D audio amplifier is basically a switching amplifier or PWM amplifier. There are a number of different classes of amplifiers. This application note takes a look at the definitions for the main classifications.
App note: How to pick a click-and-pop suppressor
Audio noises click-and-pop suppression method from Maxim. Link here (PDF) This application note presents the MAX9890 and MAX9892 which use different approaches to remove audible click and pop from headphones. Each device is uniquely suited to different applications.
App note Quick-Start: Driving 14-segment displays with the MAX6954
Guidelines from Maxim on using the MAX6954 to drive 14-segment monocolor LEDs, app note here (PDF!): This article is how-to guide, intended as a quick learning aid for engineers considering using the MAX6954 to drive 14-segment monocolor LEDs. The MAX6954 is a versatile display driver, capable of controlling a mix of discrete, 7-segment, 14-segment, and 16-segment […]
An Arduino Terminal
Peter Scargill writes, “As it happens I’m experimenting on a 1284 chip which while being Arduino-compatible kind of, it does have another serial port, so without disconnecting my FTDI – I hooked up the second serial port to the home control serial and fired the DEBUG command at the latter. As you can see […]
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 to two random commenters. The coupon code usually go to Facebook ‘Other’ Messages Folder . More PCBs via Twitter on Tuesday and the blog every Sunday. Don’t forget there’s free PCBs three […]
Teardown of a Static fieldmeter
A teardown of a Static fieldmeter from Kerry Wong: Static fieldmeters (or electrostatic fieldmeters) are typically used for non-contact measurements of the electrostatic field strength (usually in kV) of charged objects. These are highly specialized test instruments and most hobbyists probably seldomly have the opportunity of coming across one. So in this post and a companion video […]
PRU tips: Understanding the BeagleBone’s built-in microcontrollers
Ken Shirriff writes, “The BeagleBone Black is an inexpensive, credit-card sized computer that has two built-in microcontrollers called PRUs. While the PRUs provide the real-time processing capability lacking in Linux, using these processors has a learning curve. In this article, I show how to run a simple program on the PRU, and then dive into […]
Teardown and analysis of an Agilent 86109B Optical/Electrical DCA-X oscilloscope module
Teardown and analysis of an Agilent 86109B Optical/Electrical DCA-X oscilloscope module from The Signal Path: In this episode Shahriar presents the inner workings of an Agilent 86109B optical/electrical DCA-X oscilloscope module. This particular model offers up to 50GHz of electrical bandwidth and an optical input capable of receiving up to 40Gb/s data rates. The differences […]
VHF Frequency Counter with PC Interface
Scott has published a new build: This is the general idea behind how this frequency counter works. It’s so simple! It’s entirely digital, and needs very few passive components. sn74lv8154 is configured in 32-bit mode (by chaining together its two 16-bit counters, see the datasheet for details) and acts as the front-end directly taking in […]
App note: Using Cymbet™ EnerChip™ batteries instead of coin cells and super capacitors
High charge/discharge cycle and solid state reliability EnerChip from Cymbet make this a good replacement for super caps and coin cell backup batteries. Link here (PDF) Primary and secondary (i.e., rechargeable) coin cell batteries, as well as super capacitors, have been in use for years as auxiliary power sources for applications including SRAM, real-time clocks, […]
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: Battery fuel gauge IC (LC709203F) for 1-Cell Lithium-ion (Li+)
Lithium-ion fuel gauge IC from ON Semiconductors. Link here (PDF) The LC709203F is an IC that measures the remaining power level of 1-cell lithium-ion (Li+) batteries used for portable equipment etc. This product reduces fuel gauge errors with a unique correction technology during measurement of battery temperature and voltage. This technology has inherently high precision […]
App note: Crystal oscillator basics and crystal selection for rfPICTM and PICmicro devices
The basics of crystals and crystal oscillators application note from Microchip, link here (PDF!) This Application Note will not make you into an oscillator designer. It will only explain the operation of an oscillator in simplified terms in an effort to convey the concepts that make an oscillator work. The goal of this Application Note is […]
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 to two random commenters. The coupon code usually go to Facebook ‘Other’ Messages Folder . More PCBs via Twitter on Tuesday and the blog every Sunday. Don’t forget there’s free PCBs three […]
Portable temperature, humidity and light ambient datalogger
A battery-powered small datalogger based on a PIC18F2620 microcontroller project from Jesus Echavarria: The idea comes a few months ago, talking with a friend. He needs something to monitoring temperature and humidity inside a sea container, for a three weeks travel from Spain to China. Low consumption is important, in order to have maximum autonomy with […]
DIY Desktop CNC with an Arduino
Bob Davis has been working on rebuilding his DIY CNC machine: I have been busy rebuilding my DIY CNC machine. It will be all metal when I get done. It will also include a USB interface, likely an Arduino. None of my computers have a parallel port these days. So something has to be done to […]
ICS501 simple frequency multiplier
Scott from SWHarden has published a new build: Today I made a high frequency multiplier using a single component: the ICS501 PLL clock multiplier IC. This chip provides 2x, 5x, 8x (and more) clock multiplication using an internal phased-lock loop (PLL). At less than a dollar on eBay, $1.55 on mouser, and $0.67 on Digikey, […]