App note: Power source ON/OFF characteristics for linear regulator

an_rohm_linearreg_power-on-off_an-e

A good read app note from ROHM on linear regulator On and Off characteristic. Link here (PDF)

When a linear regulator IC is turned ON, the electric charge is stored in the output capacitor and the output voltage increases up to the specified value. At this time, an inrush current flows from the input to output of the IC. The output voltage drops when the input power source is disconnected. This application note explains the series of operations when the power source is turned ON/OFF.

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Free PCB coupon via Facebook to 2 random commenters

BP

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 times every week:

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • We’ll contact you via Facebook with a coupon code for the PCB drawer.
  • Limit one PCB per address per month, please.
  • Like everything else on this site, PCBs are offered without warranty.

We try to stagger free PCB posts so every time zone has a chance to participate, but the best way to see it first is to subscribe to the RSS feed, follow us on Twitter, or like us on Facebook.

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Sense energy monitor teardown – sampling in MHz

Sense Energy monitor teardown

Tisham Dhar did a teardown of a Sense Energy monitor:

Recently I obtained a Sense Energy monitor via US from Margaret of BitKnitting. She is doing a very interesting neighbourhood energy efficiency project. As usual I could not contain my curiosity and opened it up to have a look. I will start off with an analogy – the closest bit of open-source kit that I have to do half the amount of analog functions as the Sense is the PRUDAQ on the BeagleBone wifi

More details on his blog.

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App note: Application of SiC MOSFETs

an_on_AD9691-D

App note from ON Semiconductors about Silicon Carbide MOSFETs, their difference and gains over Silicon MOSFETs. Link here (PDF)

Among the Wide Band Gap materials silicon carbide (SiC) is by far the most mature one. The raw wafer quality has greatly improved over the last years with significant reduction of micro pipes and dislocations. Silicon carbide devices can work at high temperatures, are very robust and offer both low conduction and switching losses. The high thermal conductivity makes SiC also a perfect choice for high power applications, when good cooling is required. Compared to silicon switches, silicon carbide MOSFETs inherit some specific characteristics like the shift of gate threshold a designer should be aware of. This effect will be explained in this application note.

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BML HDMI video for FPGAs over PMOD

BML HDMIvideoforFPGAs over PMOD

Here are two open-source-hardware HDMI  video boards for adding digital video to FPGA platforms with standard PMOD connectors from Black Mesa Labs:

The BML 3bit HDMI over single-PMOD uses 7 of 8 available LVCMOS 3.3 pins on a single PMOD to provide 3bit color ( R,G,B 100% On or Off ). Example Verilog design drives 800×600 using a 40 MHz dot clock. The TI TFP410 is very versatile in the resolutions it can generate and is really just limited by the clock that the FPGA can provide and the data rates the PMOD connectors are capable of.

More details at Black Mesa Labs homepage.

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Free PCB coupon via Facebook to 2 random commenters

BP

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 times every week:

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • We’ll contact you via Facebook with a coupon code for the PCB drawer.
  • Limit one PCB per address per month, please.
  • Like everything else on this site, PCBs are offered without warranty.

We try to stagger free PCB posts so every time zone has a chance to participate, but the best way to see it first is to subscribe to the RSS feed, follow us on Twitter, or like us on Facebook.

from Dangerous Prototypes http://ift.tt/2yGjX45

Teardown of an Extech 380460 milliohm meter

Extech380460

Kerry Wong did a teardown of an Extech 380460  miliohm meter:

This is a highly specialized instrument, all it does is measuring low ohm range resistance (from 200mΩ to 2000Ω in five ranges) and nothing else. The meter came with a rugged case which is handy for field use, although its portability is hampered by the requirement of a wall outlet.
Since this meter is designed for low resistance measurement, it came with a set of 4 wire Kelvin clips. The stock leads are not my favorite though, as the design uses rubber rings to hold the two clip pieces together. One issue of this (instead of proper spring tensioned clips) is that the tension is quite weak and it is difficult to make secure contact with small dimension leads. Also, the rubber ring is likely to lose tension and fail over repeated use.

See the full post on his blog.

Check out the video after the break.

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