ON semiconductor’s application note on faster charging of Lithium Ion batteries with consideration on heat suppression. Link here (PDF) Currently, because LiB (Lithium Ion Battery) is superior in current density and electromotive force, it becomes mainstream of batteries for mobiles such as smart phone. However, because LiB is weak at over-charge and over-discharge, a control […]
Author Archives: DP
App note: Application precautions: Power MOSFET application notes
Toshiba’s application note on the things to consider when picking a power MOSFET. Link here (PDF) This document explains selecting MOSFETs and what we have to consider for designing MOSFET circuit, such as temperature characteristics, effects of wire inductance, parasitic oscillations, avalanche ruggedness, and snubber circuit.
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 […]
Building an AT2XTKB (AT to XT) keyboard adapter on prototype board
Matt built an AT2XT keyboard adapter on prototype board using an AT to PS/2 keyboard cable. Project info at Matt’s Tech Pages.
Sony TC-252 reel to reel player restoration
Dilshan Jayakody has written an article about Sony TC-252 reel to reel player repair: As a first step of the restoration we remove the LA4440 module attached into that recorder and rewire the player with original wiring layouts. After rewiring we check all the transistors in that player and find-out that the couple of 2SC634 […]
Inside the 74181 ALU chip: die photos and reverse engineering
A detailed die photos and reverse engineering of the 74181 ALU chip by Ken Shirriff: What’s inside a TTL chip? To find out, I opened up a 74181 ALU chip, took high-resolution die photos, and reverse-engineered the chip.1 Inside I found several types of gates, implemented with interesting circuitry and unusual transistors. The 74181 was a […]
Printed Circuit Board V-Groove cutting machine
This is how V-Grooves are cut into PCBs. V-Grooves are half-cuts into the PCBs that allow them to be snapped apart easily. Minimum V-Groove cut length in generally 8cm due to machine cutting length. V-Grooves must be cut across the entire PCB length, it is not possible to make short internal cuts. This is from […]
#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 […]
Tear down of a super capacitor
A teardown video of a 1 Farad super capacitor from Electronupdate: In a recent video on the tear down of an electrolytic cap a viewer was wondering what a super capacitor looks like. They have much more capacitance: 10,000 time more on average for the same volume. Surely this means the physical construction must be amazing! Interestingly […]
EasyESP-1: a rapid prototyping and development board for ESP8266
Raj over at Embedded Lab has designed a development board for ESP8266: EasyESP-1 is a rapid prototyping board for the low-cost, WiFi-enabled ESP8266 microcontroller. With an onboard USB-to-Serial converter pre-installed, EasyESP-1 does not require any additional hardware to download your application firmware to the ESP8266 chip. The ESP module used in this development board is […]
Curtis 1231C-8601 500A PWM DC motor controller teardown
Jay did a teardown of a Curtis 1231C-8601 500A PWM DC motor controller: The Curtis 1231c-8601 power board is relatively simple. It uses 18 MOSFETS in parallel to switch current from the motor- terminal back to the battery- terminal (the motor+ lead is already connected to battery+). The MOSFETs it uses are IXYS IXTH50N20 SP9536 chips. […]
App note: Redefining a new state-of-the-art in microampere current-sense amplifiers
Silicon Lab’s TS1100 and TS1101 current sense amplifier’s features discussed in this app note. Link here (PDF) Sensing and controlling supply current flow are a fundamental requirement in most all electronic systems from battery-operated, portable equipment to mobile or fixed-platform power management and dc motor control. High-side current-sense amplifiers (or “CSAs”) are useful in these […]
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: Multiple Capture/Compare/PWM (MCCP): Extending the functionality for low-cost motor control applications
Microchip’s MCCP module on PIC32 devices demonstrate the built-in majority detection filter for simpler motor control drives. Link here (PDF) The motor control industry has been focusing on designing low-cost motor control drives for various applications. The consumer demand for low-cost motor control applications is driving this trend. Microchip has recently introduced the PIC32MM family […]
Qume 842 8″ floppy drive with a RC2014 Z80 retrocomputer
Dr. Scott Baker writes, “In this video, I try out some Qume 8 inch floppy drives that I bought on eBay. I interface them to a WD37C65 controller on my Z80 CP/M computer and I format the disks and read/write some files to them.” More details at Dr. Scott M. Baker’s blog.
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 […]
LiPo batteries hacking and refurbishing
Karman wrote an article showing how to refurbish dead batteries to extend its life: One of the difficult parts when prototyping is to find reliable power sources. Today is still hard to find the battery size we want to use because country exporting frontiers stops these chemical packages. Here I’ll show how to refurbish dead batteries […]
DIY Arduino GRBL CNC with a laser
A DIY Arduino GRBL CNC with a laser from Bob Davis. Project info at Bob Davis’ blog.
EAGLE: Panelizing made easy
Sjaak shared a tip for panelizing PCB boards in Eagle: Panelizing is done by machining a slot between two or more boards, but keep them attached by a small amount of PCB material (mousebites). I used to do it by hand: generated all the schematics into multiple sheets and then route the board and finally […]
#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 […]