Application note from International Rectifier on MOSFET paremeters to consider when designing a Class D audio amplifier. Link here (PDF) Class D audio amplifier is a switching amplifier that consists in a pulse width modulator (with switching frequency in order of several hundred kHz), a power bridge circuit and a low pass filter. This type […]
Author Archives: DP
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 […]
Network cable tester
Dilshan Jayakody writes, “This is an automatic Cat6 / Cat5 network cable tester designed using NE555 timer and 4017 decade counters. This unit test all 8 wire lines of twisted pair network cable and indicate pass/fail status with single LED. We design this unit to test network connectivity issues in Cat6 / Cat5 cable systems […]
DIY ISA game control adapter with parallel IO
Dr. Scott Baker has published a new build: My Xi 8088 homebuilt PC is a testament to the spirit of DIY and customization. Just as I am aiming to streamline my PC by combining the functions of a game control adapter and an 8255 PIO board into one slot, I appreciate the efficiency of platforms […]
Building a high capacity battery bank
Kerry Wong has been working on building a high capacity battery bank using his DIY tab welder. More info on his blog here.
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: 12Vac LED Driving without smoothing capacitors
Application note from Diodes Incorporated on driving 12Vac LED without smoothing capacitors with their Zetex ZXLD1360 LED driver IC and SBR2A40P1 super barrier rectifier. Link here (PDF) LED based architectural lighting is now coming of age, but there are still some problems to be considered when designing luminaires to be fitted into existing installations. This […]
App note: CAN Bus – Common high speed physical layer problems
App note from Vector on three commonly encountered high speed CAN physical layer problems – bus termination, signal levels, and ground. Link here (PDF) Determining the exact cause of a CAN problem is not at all simple. Is the problem in hardware or software? Is the problem on the circuit board or on the CAN […]
The Boat PC – a marine based Raspberry Pi project
Domipheus has published a new build: In late 2015 I was doing my usual head-scratching about what gifts to get various family members for the holiday season. My wife mentioned making something electronic for my father-in-laws boat, and after a few hours of collecting thoughts came up with an idea: A Raspberry Pi computer, which […]
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 and experiments with a Doppler microwave transceiver
Kerry Wong did a teardown of Microsemi’s C900502 X-band planar transceiver: I got a couple of Microsemi’s C900502 10.525 GHz X-band Doppler radar motion sensors a while ago. This batch was made in UK and had “UK patents 2243495 and/or 2253108 apply” printed on the case. I have seen a teardown of an HB100 Doppler […]
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: Through-Hole versus SMD components
App note from Vishay on the advantages of using Through-Hole mounting. Link here (PDF) Most electronic gadgets are designed to interface with humans, and we humans are very abusive to most electronic devices. We drop them, poke them, open and close them, and in general feed stuff into and out of them. It is well […]
App note: Thermal management in surface-mounted resistor applications
App note from Vishay on PCB thermal management specifically on components like SMD resistors, where if allowed a design change (e.g. change in SMD size or change in more heat tolarant ones) must be implemented in order to squeeze more thermal capability. Link here (PDF) Thermal management is becoming more important as the density of […]
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 […]
Bus Pirate v3.8 free PCB build
@ramin_rajabi tweeted picture of his free Bus Pirate v3.8 PCB build. 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 […]
Precision voltage source – voltage calibrator
Mare writes, “What I missed in my workshop is nifty small programmable precision voltage source which can be used as calibration voltage source for testing and calibration purposes. I decided to make one, because instruments which have word “calibrator” have price with same digits as there is vocals in this magic word.” More details at Mare […]
Teardown of a Philips dimmable LED bulb
Kerry Wong did a teardown of a Philips dimmable LED bulb: One of the first things you will notice about this light bulb is that the compact construction. Most noticeably the lack of the telltale heatsink fins. As a result however, the heat dissipation capability is greatly sacrificed. During normal operation when mounted pointing downwards […]
App note: Minimizing the temperature dependence of digital potentiometers
Application notes from NIDEC COPAL Electronics Corp. about digital potentiometer’s temperature dependence. Link here (PDF) The digital potentiometers (DP) has two temperature dependent parameters, the TC of the end-to-end resistance Rpot and the ratiometric TC. The temperature dependence of the parameters of an analog circuit using a digital potentiometers is reduced if the performance of […]
App note: Potentiometers and trimmers
App note from Vishay on variable resistors primer. Link here (PDF) A potentiometer is a mechanically actuated variable resistor with three terminals. Two of the terminals are linked to the ends of the resistive element and the third is connected to a mobile contact moving over the resistive track. The output voltage becomes a function […]