Categories

App note: USB audio bridge example with STM32F0 MCUs

Posted on Sunday, July 22nd, 2018 in app notes by DP | No Comments

an_stm_DM00189562

App note from STMicroelectronics using their STM32F0 microcontrollers to playback audio stream from USB. Link here (PDF)

This application note describes a method and an example of synchronizing audio playback or audio recording with an upstream or downstream USB audio host, ensuring flawless audio listening or recording using only internal MCU resources.

Focusing on specific properties of USB microcontrollers from the STM32F0 family, the application note describes how the CRS unit can be beneficially employed for USB audio streaming synchronization. In particular, it elaborates a method of HSI48 clock frequency trimming to compensate for timing differences due to independent USB host (computer) and device (STM32F0) clock domains.

Twin ‘T’ CW (Morse) Practice Oscillator

Posted on Friday, July 20th, 2018 in PCBs by DP | No Comments

 

CW_Practice_Oscillator_Prototype

Steve Smith (G0TDJ) writes, “I successfully completed the Twin ‘T’ Oscillator, original by Mike Maynard – K4ICY. It’s a great circuit and sounds really good. Much better than a raspy 555 version. Mike has been kind enough to put a link to my project on his website.”

More details at www.ProjectAVR.com.

Free PCB coupon via Facebook to 2 random commenters

Posted on Friday, July 20th, 2018 in Free PCBs by DP | No 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…)

How to use I2C LCD with ESP32 on Arduino IDE

Posted on Thursday, July 19th, 2018 in Arduino, tutorials by DP | No Comments

LCD-display-featured-image-600

A how-to on using an I2C LCD display with the ESP32 using Arduino IDE from Random Nerd Tutorials:

This tutorial shows how to use the I2C LCD (Liquid Crystal Display) with the ESP32 using Arduino IDE. We’ll show you how to wire the display, install the library and try sample code to write text on the LCD: static text, and scroll long messages. You can also use this guide with the ESP8266.

See the full post at randomnerdtutorials.com.

Hand soldering a WLCSP package

Posted on Wednesday, July 18th, 2018 in how-to by DP | No Comments

MSOP-10 soldering video at mitxela.com:

I admit that when I made the video of me soldering an MSOP-10 package, I did it because I needed to use the chip right away, and didn’t have time to order a breakout board. But this time, I am just doing this for fun.
MSOP is smaller than TSSOP which is smaller than SOIC which is smaller than DIP. Although the pin pitch is larger, the physical size of the ATtiny9 in the charliestar project is smaller than the MSOP-10 package. Most ATtiny parts are also available in QFN format, which has a smaller rectangle with pads around the edges. But there’s a fundamental limit to how close you can put adjacent pins and still have them reflow correctly.

More details at mitxela.com.

DC voltmeter test gadget

Posted on Tuesday, July 17th, 2018 in DIY, gadget, testing by DP | No Comments

test gadfet dcvm-600

DuWayne posted an update on his test gadget project we covered previously:

The picture shows the completed DCVM test gadget in 4 channel mode measuring the 3 voltages present on the headers used to connect the individual test gadgets.  I was running this off of the PC without the 12 volts connected for external power, so I kept the range down to 5 volts.

See the full post on DuWayne’s Place blog.

PSoC5 Grbl with Native USB

Posted on Tuesday, July 17th, 2018 in USB by DP | No Comments

usb

bdring at Buildlog.Net writes:

I added native USB support to my PS0C5 port of Grbl. The PSoC has USB capability on the chip. It also has a component for using it as a USB UART (CDC Interface). This means it looks like a serial port to the connected PC and uses the standard CDC interface driver that most OS have.
I am currently only using this on the PSoC5 development board so I am comfortable using their VID and PID values. If I make some custom hardware and distribute it, I will need to get my own.

See the full post on Buildlog.net blog.

#FreePCB via Twitter to 2 random RTs

Posted on Tuesday, July 17th, 2018 in Free PCBs by DP | No Comments

IRToy-600x369

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.

Controlling an HMC624LP4E RF attenuator using Arduino

Posted on Monday, July 16th, 2018 in Arduino, Interface by DP | No Comments

HMC624LP4EArduino-600

Kerry Wong writes:

For simplicity, I used a single rotary encoder for controlling the attenuation. In order to prevent accidentally changing the set attenuation value, I used the built-in switch of the rotary encoder as the lock/adjust control. The idea is that the attenuation value can only be adjusted when the switch is in the “adjust” state and the attenuation value is set once the switch changes from adjust to the lock state. When the switch is in the “locked” state, adjusting the rotary encoder has no effect on the digital attenuator. The current attenuation value is displayed on a 1×16 LCD. For more details, you can find the Arduino code listing towards the end of this post along with a video demonstrating this control interface.

More details on Kerry Wong’s blog.

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

A limited attenuation high-pass filter for the KiwiSDR

Posted on Monday, July 16th, 2018 in DIY, RF by DP | No Comments

limited_10MHz_HPF_inside_1a-600

KA7OEI published a new build:

One of the issues common with using a broad-band, direct-sampling SDR (software-defined radio) like the KiwiSDR is that of overload by strong, low-frequency signals, such as those on the AM (mediumwave) broadcast band – but there’s another problem that should be considered as well:  The high generally-high signal levels at lower HF frequencies.  If one looks at an spectrum analyzer connected to a broad-band receive  antenna during the evening, one will immediately note that the lower the frequency, the higher the signals seem – particularly the background noise.

See the full post on KA7OEI’s blog.

Free PCB Sunday: Pick your PCB

Posted on Sunday, July 15th, 2018 in Free PCBs by DP | 14 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: USB Type-C protection and filtering

Posted on Sunday, July 15th, 2018 in app notes by DP | No Comments

an_stm_DM00294046

STMicroelectronics’ solution for simplifying USB Type-C protection and filtering using transient voltage suppressors, common mode filtering and proper board layout. Link here (PDF)

The USB interface has been present on the market for nearly 2 decades and thanks to that, nowadays it is quite obvious for everybody to connect electronic devices in this manner. However, the presence of different types of connectors: type A, type B, mini USB, micro USB etc., makes difficult and complicated the choice of the right one. For this reason USB Type-C, a unique connector to drive audio and power data up to 5 or 10 Gbps, is now available.

Due to the fact that for its own nature a connector is a link to the outside world, it may be exposed to a lot of disturbances which can ruin the transceivers. Moreover, the high-speed links radiate therefore an efficient filter has to be used to solve antenna desense.

STMicroelectronics has developed some specific protection devices and common mode filters with optimized performance and layout.

App note: How to select the right thyristor (SCR) for your application

Posted on Sunday, July 15th, 2018 in app notes by DP | No Comments

an_stm_DM00140125

SCR fundamentals discussed in this app note from STMicroelectronics. Link here (PDF)

This document provides some guidelines about how to select the right thyristor, also referred to as “SCR”, according to the different applications. Some very specific cases could require a higher level of expertise to ensure reliable and efficient operation.

 

Dual ultrasonic sensors combine for 2D echolocation

Posted on Friday, July 13th, 2018 in Arduino, sensors, tutorials by DP | No Comments

F4UGJR8JIXQHU3D-600

A how-to on making a Dual-sensor ultrasonic echo locator by lingib, project instructables here:

This instructable explains how to pinpoint the location of an object using an Arduino, two ultrasonic sensors, and Heron’s formula for triangles. There are no moving parts.
Heron’s formula allows you to calculate the area of any triangle for which all sides are known. Once you know the area of a triangle, you are then able to calculate the position of a single object (relative to a known baseline) using trigonometry and Pythagoras.
The accuracy is excellent. Large detection areas are possible using commonly available HC-SR04, or HY-SRF05, ultrasonic sensors.
Construction is simple … all you require is a sharp knife, two drills, a soldering iron, and a wood saw.

Via Arduino Blog.

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

Free PCB coupon via Facebook to 2 random commenters

Posted on Friday, July 13th, 2018 in Free PCBs by DP | No 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…)

Wavecatcher

Posted on Thursday, July 12th, 2018 in PCBs by DP | No Comments

IMG_4753-600

Anfractuosity published a new build:

“Acoustic cryptanalysis is a type of side channel attack that exploits sounds emitted by computers or other devices”

Wavecatcher is a simple PCB that makes use of a MEMS ultrasound microphone, in order to capture audio to around 80kHz, with the goal
of finding interesting ultrasound sources and playing with exfiltrating data from SMPSs etc. via ultrasound.

See the full post on Anfractuosity’s project page and the GitHub repository here.

Electronic key tear down

Posted on Tuesday, July 10th, 2018 in Teardowns by DP | No Comments

dallas_top-600

Tear down of an Electronic key  from Electronupdate:

In the mid 1980’s a company called Dallas Semiconductor was producing a wide range of small RAMs with integrated battery backup. One of the more unusual item was an early attempt at an electronic key: a user would be issued a key which could then be typically used to allow access to equipment and to keep track of usage. Not very secure by today’s standards…. but an interesting data point.
Opening it up shows that it had two major parts: a silicon die and a battery. The amount of ram on the die was very small, 256 bits!

More details on Electronupdate blog.

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

#FreePCB via Twitter to 2 random RTs

Posted on Tuesday, July 10th, 2018 in Free PCBs by DP | No Comments

IRToy-600x369

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.

ESP32 with multiple DS18B20 temperature sensors

Posted on Monday, July 9th, 2018 in tutorials by DP | No Comments

multiple-ds18b20-temp-sensor-thumbnail-600

Guide to ESP32 with multiple DS18B20 temperature sensors from Random Nerd Tutorials:

This guide shows how to read temperature from multiple DS18B20 temperature sensors with the ESP32 using Arduino IDE. We’ll show you how to wire the sensors on the same data bus to the ESP32, install the needed libraries, and a sketch example you can use in your own projects. This tutorial is also compatible with the ESP8266 and the Arduino boards.

Teardown of an MVMT dual USB port wall outlet adapter

Posted on Monday, July 9th, 2018 in Teardowns by DP | 1 Comment

MVMTUSBOutlets-600

Kerry Wong did a teardown of an MVMT dual USB port wall outlet adapter:

Specification wise, the adapter is rated to provide 2.1A for its USB output. I did some load testing with an electronic load I built before and it appeared that the 2.1A is rated for the combined output from both USB ports. You can see my testing in the video linked towards the end of this post. This means that if you are charging two devices using this adapter, charging time will be lengthened as the 2.1A output current has to be shared between the two channels.
The internal build quality of this MVMT USB adapter is actually quite good. Two PCBs are used in this adapter. One is for surge protection and the other one is for the switching power supply that generates the 5V output rails.

See the full post on his blog here.

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

Next Page »

Recent Comments

  • Dario: Hi, I have a doubt: is it possible configure the FTDI using a I2C and an SPI channels together in the same time? BR Dario
  • Andrew: Me!!
  • Klebiano Kennedy: A pack of PCB for trip, please.
  • Crawford: Kumquats!
  • Iain: Random Sunday