Ken Shirriff writes, “A die photo of a vintage 64-bit TTL RAM chip came up on Twitter recently, but the more I examined the photo the more puzzled I became. The chip didn’t look at all like a RAM chip or even a TTL chip, and in fact appeared partially analog. By studying the chip’s […]
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 […]
Solid-state joystick
Paul Gardner-Stephen writes: Early in the year, one of my colleagues, Damian, showed me one of these strain-gauge solid-state joysticks that they were using as part of the undergraduate engineering curriculum. Their goal was to teach the students how to read strain-gauges. But I immediately saw the applicability for making a no-moving-parts super-robust joystick for […]
Microcontroller action potential generator
Scott Harden writes: Here I demonstrate how to use a single microcontroller pin to generate action-potential-like waveforms. The output is similar my fully analog action potential generator circuit, but the waveform here is created in an entirely different way. A microcontroller is at the core of this project and determines when to fire action potentials. […]
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: How RF transformers work and how they are measured
Application note from Mini-Circuits about transformers, this time the RF transformers. Link here (PDF) RF transformers are widely used in electronic circuits for * Impedance matching to achieve maximum power transfer and to suppress undesired signal reflection. * Voltage, current step-up or step-down. * DC isolation between circuits while affording efficient AC transmission. * Interfacing […]
App note: Transformers
App note from Mini-Circuits on transformer types and some basics of them. Link here (PDF) The purpose of this application note is to describe the fundamentals of RF and microwave transformers and to provide guidelines to users in selecting proper transformer to suit their applications. It is limited to core-and-wire and LTCC transformers.
App note: USB hardware design guide
An app note from Silicon Labs with design guidelines for implementing USB host and device applications using USB capable EFM32 microcontrollers. Link here. (PDF!) This document will explain how to connect the USB pins of an EFM32 microcontroller, and will give general guidelines on PCB design for USB applications. First some quick rules-of-thumb for routing […]
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 […]
PRECIsion Power SUpply project
PreciPSU, a high performance power supply project from Mare & Gal Electronics: PreciPSU is an attempt to build high performance power supply. The idea started few years ago but it was never realised. Some major target performance specs are as follows: three isolated channels around 50W per channel 24V/3A output per channel lowest possible ripple at fastest […]
Getting control over a 50 watt CO2 laser cutter from China
Unboxing laser cutter Co2 50 watt from China: There are people around me who think I’m crazy. And they are probably right. Who else would buy a machine from someone he does not know. I have to pay upfront. It is not clear how things will get delivered, what gets delivered, or if it gets delivered […]
#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 […]
Bus Pirate free PCB build
Martin built these free Bus Pirate PCBs. 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 your own […]
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: Selecting a FET for use with the Si875x driver
Another application note from Silicon Labs on determining the proper FET used on their Si875x driver based on its application. Link here (PDF) The Si875x enables creating custom solid state relay (SSR) configurations. Supporting customer-selected external FETs, the Si875x combines robust isolation technology with a FET driver to form a complete, isolated, switch. Versatile inputs […]
App note: Driving MOSFET and IGBT switches using the Si828x
App note from Silicon Labs on their MOSFET and IGBT driver Si828x and how to determining its external components to achieve optimized performance. Link here (PDF) The Si828x products integrate isolation, gate drivers, fault detection protection, and operational indicators into one package to drive IGBTs and MOSFETs as well as other gated power switch devices. […]
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 […]
A look inside the DS3231 real-time clock
Pete posted an article taking a closer look at Maxim’s DS3231 real-time clock: Fortunately, Maxim also offers the DS3231, which is advertised as an “Extremely Accurate I2C-Integrated RTC/TCXO/Crystal”. This chip has the 32kHz crystal integrated into the package itself and uses a built-in temperature sensor to periodically measure the temperature of the crystal and, by […]
Teardown and repair of an Agilent 53152A 46GHz microwave frequency counter
Agilent 53152A 46GHz frequency counter teardown and repair from The Signal Path: In this episode Shahriar investigates a faulty Agilent 53152A 46GHz frequency counter. The instrument does not power on and shows no sign of internal voltage presence. Teardown of the instrument reveals a large PCB where all analog and digital circuity is contained. The power supply […]
App note: Gate drive characteristics and requirements for HEXFET power MOSFETs
App note from International Rectifier on driving their Power MOSFETs. Link here (PDF) The conventional bipolar transistor is a current-driven device. A current must be applied between the base and emitter terminals to produce a flow of current in the collector. The amount of a drive required to produce a given output depends upon the […]