Categories

Battery adapter teardown and Sony A6000 power-off current draw

Posted on Wednesday, July 19th, 2017 in Teardowns by DP | 1 Comment

 

poweroffcurrent-600

Kerry Wong did a teardown  of a battery adapter for the Sony A6000 mirrorless digital camera and measured the poweroff current draw of the the camera:

With the battery adapter on hand, I decided to take a look at what’s inside and then use the adapter to measure the power-off/stand-by current of the Sony A6000.
I was not expecting to see much inside this battery adapter. After all, all it needs is the connection between the battery terminals and the input power jack and a resistor between the center pin and the ground in place of the thermistor that is used to sense the temperature of the battery pack. At the most, it might also include a reverse polarity protection diode.
But a quick measurement suggested that there must be some active components inside as the adapter itself draws around 17 µA current when connected to the power source. So clearly, there is some active circuitry inside.
Upon opening up the battery adapter, I was surprised to see the circuit board inside.

More details on Kerry D. Wong’s blog.

Check out the video after the break. (more…)

Bus Pirate v3 free PCB build

Posted on Wednesday, July 19th, 2017 in builds, Bus Pirate by DP | No Comments

1freepcbbuild

@vijayenthiran tweeted picture of his free Bus Pirate v3 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 drawer.

Get your own handy Bus Pirate for $30, including world-wide shipping. Also available from our friendly distributors.

#FreePCB via Twitter to 2 random RTs

Posted on Tuesday, July 18th, 2017 in Free PCBs by DP | No Comments

BP

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 it every Sunday, right here on the blog
  • Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
  • Facebook PCB Friday. Free PCBs will be your friend for the weekend

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • Check out how we mail PCBs worldwide video.
  • We’ll contact you via Twitter 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.

Pogo pin test board for ADB-USB Wombat

Posted on Tuesday, July 18th, 2017 in testing by DP | No Comments

pics-20170716_150939-600

A pogo pin tester for the ADB-USB Wombat board from Big Mess o’ Wires:

Here’s a test rig for the ADB-USB Wombat board: my first-ever project whose sole purpose is to facilitate testing of another project. It uses spring-loaded pogo pins to create a bed of nails that fit into test points on the Wombat board. I can drop a new Wombat board onto the tester, clamp it in, and then program and test it with just a few button clicks. This is a huge improvement over my old manual testing method, which involved multiple cable connections and disconnections, and hand-verified keyboard/mouse emulation on two separate computers. That sort of test process is fine for building a few units, but something faster and easier is needed to support higher volume assembly.
Pogo pins contain tiny internal springs. When a Wombat board is pushed down onto the bed of pins, they compress a few millimeters in length. This helps to create a reliable electrical contact for each pin, even if the uncompressed lengths of the pogo pins are slightly different or they’re not perfectly aligned.

Check out the video after the break.

(more…)

Free PCB Sunday: Pick your PCB

Posted on Sunday, July 16th, 2017 in Free PCBs by DP | 19 Comments

BP-600x373

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 get a coupon code for the free PCB drawer tomorrow morning. Pick your own PCB. You get unlimited free PCBs now – finish one and we’ll send you another! Don’t forget there’s free PCBs three times every week:

(more…)

App note: Linear power MOSFETS basic and applications

Posted on Sunday, July 16th, 2017 in app notes by DP | No Comments

an_IXYS_IXAN0068

Some examples of power MOSFETS application from this app note from IXYS Corporation. Link here (PDF)

Applications like electronic loads, linear regulators or Class A amplifiers operate in the linear region of the Power MOSFET, which requires high power dissipation capability and extended Forward Bias Safe Operating Area (FBSOA) characteristics. Such mode of operation differs from the usual way of using Power MOSFET, in which it functions like an “on-off switch” in switched-mode applications. In linear mode, the Power MOSFET is subjected to high thermal stress due to the simultaneous occurrence of high drain voltage and current resulting in high power dissipation. When the thermo-electrical stress exceeds some critical limit, thermal hot spots occur in the silicon causing the device to fail

App note: Depletion-Mode power MOSFETs and applications

Posted on Sunday, July 16th, 2017 in app notes by DP | No Comments

an_IXYS_IXAN0063

IXYS Corporation’s N-Channel power MOSFET selection and application. Link here (PDF)

Applications like constant current sources, solid-state relays, telecom switches and high voltage DC lines in power systems require N-channel Depletion-mode power MOSFET that operates as a normally “on” switch when the gate-to-source voltage is zero (VGS=0V). This paper will describe IXYS latest N-Channel Depletion power MOSFETs and their application advantages to help designers to select these devices in many industrial applications.

Akafugu modular VFD clock review

Posted on Friday, July 14th, 2017 in clock by DP | 5 Comments

akafugu-vfd

Manuel Azevedo did a review of Akafugu’s modular VFD clock:

I discovered this wonderful tiny VFD clock by chance, while browsing Tindie for novelties. As I’m a newcomer to this Nixie/VFD world, I was not aware that Brian Stuckey already did an article in 2014 on a previous incarnation of this clock (Akafugu Modular VFD Clock).
I contacted Per Johan Groland, owner of the Japanese maker Akafugu that makes these clocks, for all the shields I could get my hands on – The only shield I did not order was the 4 tube IN-4/17 shield, which Brian already tested and which I find does not do this clock justice.

See the full post and more details on his blog, TubeClockDB.

Check out the video after the break. (more…)

Free PCB coupon via Facebook to 2 random commenters

Posted on Friday, July 14th, 2017 in Free PCBs by DP | 1 Comment

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:

(more…)

Inside Intel’s first product: the 3101 RAM chip held just 64 bits

Posted on Thursday, July 13th, 2017 in reversed by DP | No Comments

chip-labeled

Ken Shirriff writes:

Intel’s first product was not a processor, but a memory chip: the 31011 RAM chip, released in April 1969. This chip held just 64 bits of data (equivalent to 8 letters or 16 digits) and had the steep price tag of $99.50.2 The chip’s capacity was way too small to replace core memory, the dominant storage technology at the time, which stored bits in tiny magnetized ferrite cores. However, the 3101 performed at high speed due to its special Schottky transistors, making it useful in minicomputers where CPU registers required fast storage. The overthrow of core memory would require a different technology—MOS DRAM chips—and the 3101 remained in use in the 1980s.3
This article looks inside the 3101 chip and explains how it works. I received two 3101 chips from Evan Wasserman and used a microscope to take photos of the tiny silicon die inside.4 Around the outside of the die, sixteen black bond wires connect pads on the die to the chip’s external pins. The die itself consists of silicon circuitry connected by a metal layer on top, which appears golden in the photo. The thick metal lines through the middle of the chip power the chip.

See the full post and more details at Ken Shirriff’s blog.

#FreePCB via Twitter to 2 random RTs

Posted on Tuesday, July 11th, 2017 in Free PCBs by DP | No Comments

BP

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 it every Sunday, right here on the blog
  • Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
  • Facebook PCB Friday. Free PCBs will be your friend for the weekend

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • Check out how we mail PCBs worldwide video.
  • We’ll contact you via Twitter 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.

Halogen floodlight SMT reflow

Posted on Tuesday, July 11th, 2017 in DIY, hacks by DP | No Comments

flood_reflow_01

David Sanz Kirbis built his own reflow device with an halogen floodlight, that is available on Github:

First test was to check the speed of the temperature rise inside a standard halogen floodlight. Reflow soldering temperature curves are quite demanding, and some adapted ovens can’t reach the degrees-per-second speed of the ramp-up stages of these curves.
I bought the spotlight, put an aluminium sheet covering the inside surface of the protective glass (to reduce heat loss), and measured the temperature rise with a multimeter’s thermometer…. and wow! More than 5ºC/s… and I better turned the thing off after reaching 300ºC and still rising quickly.
So the floodlight was able to fulfill the needs.
Next step was a temperature controller, that is, the device that keeps the temperature as in a specified reflow curve profile in each moment.

See the full post and more details on his blog, TheRandomLab.

Check out the video after the break. (more…)

Free PCB Sunday: Pick your PCB

Posted on Sunday, July 9th, 2017 in Free PCBs by DP | 27 Comments

BP-600x373

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 get a coupon code for the free PCB drawer tomorrow morning. Pick your own PCB. You get unlimited free PCBs now – finish one and we’ll send you another! Don’t forget there’s free PCBs three times every week:

(more…)

App note: Infrared (IR) Spectroscopy with the SFH 473X – Background & technology

Posted on Sunday, July 9th, 2017 in app notes by DP | No Comments

an_osram_infrared_spectroscopy_SFH473X

Infrared spectroscopy by OSRAM and their SFH 473X broadband light emitters. Link here (PDF)

Imagine you can check if the mangos on the market are sweet – without even touching them…

Imagine you can verify if your prescribed medical tablets contain the life-saving compound – or if they are counterfeits…

Imagine you can check the calories of your favorite cheese dish – before eating…

Imagine all this is possible with one fingertip on your smartphone…

The SFH 473X series is precisely designed to support this innovation. This note covers briefly the background of spectroscopy and the case for the SFH 473X series.

App note: Ambient light sensors – General application note

Posted on Sunday, July 9th, 2017 in app notes by DP | No Comments

an_osram_ambient_light_sensors_gen

Different ambient sensors differs on their ability to sense specific wavelength and introduce different ambient levels compared to human eye, here’s a general application note from OSRAM. Link here (PDF)

This application note introduces discusses ambient light sensing. The different types of ambient light sensors are described and related to specific applications.

Bitcoin mining on a vintage Xerox Alto computer

Posted on Friday, July 7th, 2017 in vintage by DP | No Comments

bitcoin-finished2

Ken Shirriff writes:

I’ve been restoring a Xerox Alto minicomputer from the 1970s and figured it would be interesting to see if it could mine bitcoins. I coded up the necessary hash algorithm in BCPL (the old programming language used by the Alto) and found that although the mining algorithm ran, the Alto was so slow that it would take many times the lifetime of the universe to successfully mine bitcoins.
The Alto was a revolutionary computer designed at Xerox PARC in 1973 to investigate personal computing. It introduced high-resolution bitmapped displays, the GUI, Ethernet and laser printers to the world, among other things. In the photo above, the Alto computer is in the lower cabinet. The black box is the 2.5 megabyte disk drive. The Alto’s unusual portrait display and an early optical mouse are on top.

See the full post and more details on his blog, righto.com.

Free PCB coupon via Facebook to 2 random commenters

Posted on Friday, July 7th, 2017 in Free PCBs by DP | 3 Comments

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:

(more…)

MQ gas sensor correlation function against temperature and humidity

Posted on Thursday, July 6th, 2017 in sensors by DP | No Comments

pics-mq135_sensor_opened

Davide Gironi writes:

We have taken a look at the MQ sersor in this post here.
As I said those sensor are electro-chemical. Accuracy of those sensor is not the best. Also they will react to many gases. It means that if you are trying to measure the ppm of a certain gas with this sensor, you will have false measurement values if any of the other gas that the sensor react to, changes.
Here I will “overengeneer” on this type of sensor, trying to correlate the MQ sensor readings to temperature and humidity too, even if this correlation to me is not prominent. The correlation formula I’ve found may be wrong, so let me know if there is something to fix here.

See the full post and more details on his blog, davidegironi.blogspot.com.

65C02: Tear down, a look at the CMOS version of the 6502 CPU

Posted on Thursday, July 6th, 2017 in Teardowns by DP | No Comments

A teardown video from Electronupdate:

The CMOS version of the commercially significant 6502: a processor architecture which launched the personal computer era.
This particular version was plucked off of an embedded industrial controller… a place where this processor still finds design wins.

#FreePCB via Twitter to 2 random RTs

Posted on Tuesday, July 4th, 2017 in Free PCBs by DP | No Comments

BP

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 it every Sunday, right here on the blog
  • Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
  • Facebook PCB Friday. Free PCBs will be your friend for the weekend

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • Check out how we mail PCBs worldwide video.
  • We’ll contact you via Twitter 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.

Next Page »

Recent Comments

  • KH: Wow, after reading that, I have no desire to buy any Sony cameras, ever... My cheapo Nikon specifically mentions that a capacitor will keep the...
  • jeanmarc78: Hello everybody
  • Max: Because VFDs (just like Nixies actually) are an elegant component for a more civilized age...
  • Andrew: Me!!!
  • oliver: Sunday!