After using the PIC16F1459 to build numerous USB HID input devices including a giant keyboard, a tiny keyboard, and a big red button, it was time to see if the PIC16F1459 could be used to control outputs too. Sticking with the industrial theme, I chose to build a USB controller for a, um, stack of industrial stack lights.
Here’s a cool WiFiChron clock with 8-character alphanumeric LED display by Florinc:
For WiFiChron, two cascaded modules make an 8-character display functionally similar to HDSP-2534, but bigger and more visible. With the “Display Abstraction Layer” already in place, software support should be easy to integrate, since controlling it with the HT16K33 breakout allows the re-use of the above mentioned Adafruit LED backpack library. For maximum compatibility, I followed the same wiring, then connected the two extra segments, A2 and D2, to pin 10 (not connected for the 14-segment backpack) and pin 11 (connected to the DP), respectively.
Würth Elektronik app note on EM radiation emission from power inductors. Link here (PDF)
DC-DC converters are widely used in power management applications and the inductor is one of the key components. The usual focus is on electrical performance characteristics such as RDC, RAC and core losses. But, the electro-magnetic radiation characteristics can often be overlooked.
Due to the switching action in SMPS, AC voltage/current is produced over the inductor. Since, an inductor can, in effect, operate as a transmitting loop antenna, the electromagnetic radiation depends on a number of factors. These include the source properties such as core material, shielding material and the orientation of the start of the winding amongst others.
Electromagnetic radiation of an inductor in the low frequency spectrum range (100 kHz to 30 MHz), which is caused by the switching frequency and harmonics, is dependent on whether the inductor is shielded and the winding properties. Whereas, in the high frequency spectrum range (30 MHz to 1 GHz), where emissions are caused by ringing frequencies and their harmonics, the electromagnetic radiation is more dependent on the shielding characteristics of the core material, switching frequency and transitions of the switching converter.
A great guide from TDK about power inductors used in DC-DC converters. Link here
As electronic devices become more advanced, the power supply voltage of LSIs used in them is lowered, so their power consumption can be reduced and their speed increased. However, a decrease in the power supply voltage also causes the requirements regarding voltage fluctuations to become more severe, creating a need for high-performance DC-DC converters to fulfill these characteristic requirements, and power inductors are important components that greatly affect their performance.
Frank documented a 3D printer build, called Hephaestus:
I finally did it, I designed and built my own 3D printer. This is in no way “the best 3D printer”. Instead, this was an epic and nightmare project that exercised my ability to engineer and build my own CNC machine. Along the way, I figured out what I did well and what I did badly, mistakes were made and sometimes fixed, even ignored.
I’ve been on a quest for while now trying to build a retropie handheld that was functional but didn’t break the bank. So far I’ve made ZeroBoy – A poor man’s retropie “portable” and a follow-up ZeroBoy rev C – An improved poor mans retropie portable. These were great but I think I have made a much better system with all the features included.
Coilcraft’s app note on why inductor’s voltage ratings are uncommonly mentioned in most applications. Link here (PDF)
Voltage ratings are often specified for many electronic components, including capacitors, resistors and integrated circuits, but traditionally this has been rare for inductors. Recent trends, particularly the introduction of higher voltage rated semiconductor devices, have created a new emphasis on operating voltage as part of the inductor selection process. Inductors once considered optimized for high current, low voltage applications are finding homes in new designs that apply higher voltage stress to the inductor.
App note from Coilcraft camparing two recognized power supply topologies. Link here (PDF)
Beatles or Stones? Michael or LeBron? Deep dish or thin crust? Forward or flyback? These are just a few of the age-old questions that have been hotly debated over the years, people arguing their opinions with great vigor. But, the truth is, most of the time the answer is both, due to the merits of each.
In this article, we will focus on forward or flyback. We’ll discuss the characteristics of active clamp forward and continuous conduction flyback isolated power supply topologies and demonstrate the design and performance trade-offs of each using two telecom-oriented power supplies as examples.
HX711 is a precision 24bit ADC IC designed for weigh scales and industrial control applications to interface directly with a bridge sensor.
A load cell is a transducer that is used to create an electrical signal whose magnitude is directly proportional to the force being measured.
The library you can find here is usefull to implement a weigh scale using the HX711.