This simple circuit that converts a 5V PWM signal into a variable precision reference voltage with a rang of -2.5V to +2.5V. Many designs, like a digitally controlled power supply, programmable dummy load, etc, require a Digital to Analog Converter to supply a stable reference votlage. This circuit is cheaper and requires less pins from […]
Author Archives: DP
Circuit Lab: Sketch, simulate, and share schematics
Circuit Lab is a online electronics design suite, incorporating schematic design and simulation. It’s free of charge, and allows you to share your designs online. CircuitLab is a suite of web-based electronics design tools, including the first web-based circuit simulator with the power and accuracy needed for board-level design tasks. Explore example circuits and draw […]
CoolRunner-II breakout free PCB build
Cosminnci built a free CoolRunner-II breakout board. CPLDs are programmable logic gate arrays which allow you to build custom logic devices simply by programing them. If you build a free PCB we’ll send you another one! Blog about it, post a picture on Flicker, whatever – we’ll send you a coupon code for the free PCB […]
App note: Basic features of the Atmel XMEGA Direct Memory Access Controller (DMAC)
Here is an app note describing how to use the Direct Memory Access Controller found on Atmel’s XMEGA microcontrollers. This application note covers the basic features of the Atmel XMEGA Direct Memory Access Controller (DMAC). The goal for this training is to getting started with simple memory transfers almost without using CPU time, and reading […]
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: Lowering power consumption on PIC microcontrollers
Microchip presents several of techniques for lowering the power consumption of their PIC microcontrollers and dsPIC digital signal processors. Many things can apply to any low-power project. This document seeks to simplify the transition to low-power applications by providing a single location for the foundations of low-power design for embedded systems. The examples discussed in […]
App note: Current controlled boost driver for long LED strings
This reference design from Maxim is a current controlled boost driver designed for long strings of LEDs. Driving many LEDs in series has advantages over driving them in parallel. In a parallel configuration each LED will need it’s own current limiting resistor or current control, while the series LEDs make use of a single current […]
App note: Analog and digital conversion handbook
Ultrasounder let us know about this free online data conversion handbook from Analog Devices. It covers everything you’ll need to get started with analog-to-digital and digital-to-analog converters. It’s not just reference designs, but also theory on how various architectures function. The Data Conversion Handbook, edited by Walt Kester (Newnes, 2005), is written for design engineers […]
Biodegradable anti-static bags
All-Spec Industries contacted us about a biodegradable anti-static bag they’re selling for the same price as regular anti-static bags. They have the same properties as the normal non-biodegradable anti static bags, only these degrade within 9 months and don’t pollute the planet. We have a pile of plastic part bags sitting around from Mouser and […]
Giveaway: AVR component tester
Brent let us know he has a few extra AVR Component Tester PCBs he’d like to giveaway. His project is based on the AVR Transistor Tester which identifies electronic components like transistors and FETs, determines the pinout, and measures basic specifications. I got my PCBs and have a ton left to give away. I think […]
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. More PCBs via Twitter on Tuesday and the blog every Sunday. Don’t forget there’s free PCBs three times a every week: Free PCB Sunday. The classic. Every week, […]
Week in (p)review: March 09, 2012
Here’s a summary of major developments over the last week. Free PCB Friday is coming up soon: Free PCB: guess where @dangerousproto is going with @Finnair A box of PCBs just arrived from Seeed Studio’s Fusion PCB service 3D Model: Logic Shrimp v1.0b HOW-TO: Make parts in Cadsoft Eagle No workshop video this week, we’re […]
CPLD development boards back in stock
CoolRunner-II XC2C64A CPLD development boards are back in stock at Seeed Studio. CPLDs are programmable logic gate arrays which allow you to build custom logic devices simply by programing them. Get the CoolRunner-II development board for $15 and XC9572XL dev-board for $15.
LED dimmer using an analog knob
LEDs don’t dim well using a an adjustable resistor, instead a pulse-width modulator is usually used to blink them rapidly giving the appearance of less light. Giovanni brings the analog charm back to LED dimming by controlling brightness via an adjustment knob (machine translation). This dimmer reads the value of an adjustable trimmer resistor with […]
PlayStation 2 controller connected over a RFM12 wireless module
Dustin connected his PlayStation 2 to a PC wirelessly using two RFM12 modules to make the link. On both sides AVRs with Arduino bootloaders drive the wireless modules. All the source code for this project is available.
International Women’s Day
Happy International Women’s Day. Our community can only benefit from diversity and the involvement of anyone who wears the label engineer, hacker, or maker. Ada Lovelace, Adafruit’s namesake, is considered to be the world’s first computer programmer.
Bus Pirate v4 free PCB build
AdShea built a free Bus Pirate v4.0 PCB. The Bus Pirate is an open source hacker multi-tool that talks to electronic stuff. If you build a free PCB we’ll send you another one! Blog about it, post a picture on Flicker, whatever – we’ll send you a coupon code for the free PCB drawer. Get […]
MIT’s 6.002x Circuits & Electronics free online course
MITx is organizing a free online Circuits and Electronics (6.002x) course. The course started 2 days ago (5th of March) and will run until June. Upon completion you’ll receive an electronic MITx certificate of accomplishment. The course introduces engineering in the context of the lumped circuit abstraction. Topics covered include: resistive elements and networks; independent […]
Bus Pirate LCD adapter DIY redesign
After receiving a Bus Pirate LCD Adapter Free PCB Ashley couldn’t find any ‘595 shift register ICs, so he was forced to improvise. He redesigned the adapter by using two other logic chips to mimic the single ‘595 shift register. He also redesigned the output from a single row header to a dual row header. […]
Camera Wing for Papilio One PCB giveaway at Gadget Factory
Gadget Factory is giving away 8 Papilio One Camera wing PCBs . This can be used with a FPGA and some open VHDL code to display video on a PC. The first 8 people to send an email with a shipping address to support@gadgetfactory.net will get the free PCB’s! (Note: this is a bare PCB […]