In this article I will talk about my attempt to create flexible, compact and beautiful modular prototyping framework
Manufacture and development of electronics *
How to establish a process
http://GuitarFX.Net Digital (SOFTWARE) modeling of analog guitar distortion, reverb, noise gate etc. effects
The sound of rock music, in particular of hard rock and heavy metal, is largely based on a specially distorted guitar sound, for which electronic “distortion” devices, tube amplifiers in “overloaded” mode, computers with appropriate software and digital processors are used. increasingly using neural network algorithms.
The distorted sound of electric guitars began to gain popularity around the 1960s. Since that time, the sound of overloaded tube amplifiers, connected to powerful dedicated guitar speakers with large dedicated speakers, has been considered the benchmark in rock music. But tube amplifiers were relatively expensive and inconvenient to operate. Therefore, semiconductor distortion devices were developed.
At that time, the electrical circuitry of distortion devices was relatively simple and the signal output from their output only vaguely resembled the sound of an overloaded tube amplifier. Nevertheless, it was still somewhat similar to the “sound of a lamp” and this provided a powerful incentive for designers of analog semiconductor distortion circuits to continue their research, complicate circuits and propose new circuit solutions. The heyday of analog solid-state distortion was around 1995-2010. The most popular were electrical circuit diagrams like those shown in the figure below.
About LC ladders
LC ladder component values can have different values for the same transfer function. Published tables have only one set. Why?
Android for electronics design engineers
There is a list of well-known electronics design tools for Android which can be found in every review for the last 10 years: “Electrodoc”, “Every Circuit”, “Droid Tesla”, “Electronics Toolbox”, “RF & Microwave Toolbox” and so on. Also, there is a lot of trash on the market that turns finding a good tool into a quest.
This short review is about an unknown but cool tool “Circuit Calculator” working on Android devices and intended for professional electronics designers.
“FPGA InsideOut” – animation about CRC and parallel CRC calculation
Ссылка на русскую версию / link to Russian version
FPGA InsideOut is an attempt to make a set of educational FPGA videos presented in the “human-in-the-loop” style. In these videos we will not only show how we are interfacing with an actual FPGA board but will also provide synchronous real-time visualisation of FPGA's internal logic.
For our first video we have picked a CRC circuit (cycle redundancy check) which is based on a linear feedback shift register. This circuit goes through several transformations during the course of the video. Intrigued? - let’s watch the video.
Making an Encoder Cable for Servosila Brushless Motor Controller. Testing in Direct Drive mode
In this video, we are making a cable for connecting a quadrature encoder to a Servosila brushless motor controller, and and then running a servo motor in Direct Drive mode. To make the cable we are using a cable assembly kit that can be purchased from the internet store. Alternatively, the components for the cable can be bought in other places. The part numbers are given in the controller's datasheet.
The cable assembly kit consists of a connector and a set of wires with pre-crimped socket blades. If you have a crimper tool, you can also attach the socket blades to wires by yourself.
Lets open a datasheet document that comes with the brushless motor controller. Note that each connector has its first pin clearly marked with a "1" sign. Conventionally, the numbering of pins is done in such a way that there are rows of odd-numbered and even-numbered pins.
The quadrature encoder's electrical interface has 5 wires in total. Positions of the pins of each of the wires are given in the table. The socket blades need to be pushed into the connector until you feel a "click". The blades lock into the connector's sockets. Optionally, primarily for cosmetic reasons, you may want to add a heat-shrink tubing to your cable.
The brushless motor controllers come in two distinct forms, a circular and a rectangular one. Both models are identical in terms of capabilities, features, firmware, and external electrical connectors.
The connector has a locking mechanism that keeps it in place. I soldered a mating connector to the other side of the cable - a connector that my brushless motor needs. Note that your motor will likely require a different connector, or no connector at all. It is always a good idea to test an end-to-end integrity of the cable and its connectors. Lets buzz the wires using a multimeter. The cable is ready.
SEPIC-Ćuk split-rail converter average model
SEPIC-Ćuk split-rail converter can be used to make positive and negative supplies from a single input voltage for relatively well-matched loads like operational amplifiers.
Transient models are time consuming. Average models reduce modeling time drastically.
The PWM switch average models for current- and voltage-mode are described in details in Christophe Basso’s book “Switch-Mode Power Supplies, Second Edition: SPICE Simulations and Practical Designs”. Using of these models for SEPIC and Ćuk converters is also shown.
This text shows how to use the PWM switch average model to design a split-rail SEPIC-Ćuk converter.
High-level pipelining in TL-Verilog, RISC-V from Imagination, formal tools and open-source EDA on ChipEXPO in Moscow
This year ChipEXPO conference in Moscow invited several Western speakers to present in English the emerging technologies in high-level HDLs, formal verification, open-source EDA and using industrual RISC-V cores for education. You can join these presentations on September 14-16 for free using this link (you may need to use google translate from Russian to go through the registration) https://eventswallet.com/en/events/282/
The whole program is here
The English-speaking presentations and tutorials include:
UAVCAN HITL UAV Simulator for PX4
Hi from RaccoonLab, a team of enthusiasts in field robotics! We want to share our true-HITL UAVCAN-based simulator for PX4.
We believe a unified UAVCAN bus for drone onboard electronics will become a mainstream approach shortly. Our simulator is already based on UAVCAN (in opposition to UART-MAVLINK) and emulates exactly the same messages as real UAVCAN-sensors.
A note on small-signal modeling of SEPIC CM CCM
Knowing parameters of small-signal control-to-output transfer functions makes it easier for engineers to design compensation networks of DC/DC converters. The equations for SEPIC can be found in different works and Application Notes, but there are differences. A work has been done to solve this problem.
Simplified design equations for SEPIC with Current Mode control (CM) in Continuous Conduction Mode (CCM) suitable for practical design of compensation networks are shown.
System-on-Chip bus: AXI4 simplified and explained
Protocol AXI4 was developed for High-bandwidth and low latency applications. It is designed to allow communication between master and slave devices. Master is typically a DMA or CPU and slaves are DRAM controllers, or other specific protocol controllers: UART, SPI, and others. Sometimes one component can implement multiple instances of this protocol. Usually, a prefix is used to differentiate between multiple AXI4 interfaces.
For example, Ethernet MAC can integrate DMA and slave interface used to command MAC. MAC can accept commands on the slave interface that contain data about the location of the next ethernet packet and MAC can start fetching this packet using the separate master interface instance.
This article was motivated by common design mistakes AXI4 designers make when they are designing their Digital IP. (Looking at you Xilinx)
RS485 — a standard for industrial networks. What are the main features of the transceiver microcircuit?
When building a network for communication between a large number of devices, one may think: what interface to choose? Each interface has its own pros and cons that determine its application: CAN — Automotive, RS485 / RS232 — Industrial, Ethernet — Consumer Electronics / Server. What features of the transceiver microcircuit help to protect against many problems during installation and operation? How is the process of measuring and researching of transceiver microcircuits going on? New RS485 microcircuit is ready to get to market!
4th Order Low-pass Filter with 1 Op Amp
The idea to build a 4th order low-pass filter looks simple: add one more feedback loop. But there are pitfalls, as always.
Gyrators are impedance converters usually used to simulate inductance in circuits. Though they are rarely used in discrete electronics, they are interesting circuits looking like pole dancers in pictures. There are studies on gyrators, but still something is missing, so it is interesting to do another one.
3rd Order Low-pass Filter with 1 Op Amp
Common approach to build a 3rd order low-pass filter is to use two circuit stages and two Op Amps. Making a good One Op Amp design is not always easy, but it is possible.
Russian microcontroller K1986BK025 based on the RISC-V processor core for smart electricity meters
Solutions based on the open standard instruction set architecture RISC-V are currently increasing their presence on the market. Microcontrollers from Chinese colleagues are already in serial production; Microchip is offering interesting solutions with FPGA on board. The ecosystem of software and design tools for this architecture are also growing. Seeming previously unshaken leaders have more often found themselves in resale ads, while young startups attract multi-million investments. Milandr also got involved in this race and today began supplying interested companies with samples of its new K1986BK025 microcontroller based on the RISC-V processor core for electricity meters. Well here we go, pictures, characteristics and other information, as well as a little bit of hype under the cut.
Active Termination Drivers
The easiest way to build a driver with specified output impedance is to use an amplifier with high load compatibility and add a resistor to its output. The penalty is a voltage drop across this resistor, so there is power loss and we need a higher supply voltage. If our driver is able to deliver the same voltage and current to the same load, but the extra resistor will have a lower value, our device will be able to deliver the same output power at a lower supply voltage. Less power losses, less heat, and longer working time when a battery is used.
There is an idea how to solve this problem: active termination. We can synthesize the output impedance!
Now when we know what we want, go to design our drivers!
Compensation for Error Caused by Limited Gain-Bandwidth of Operational Amplifiers in Low-pass Filters
An operational amplifier has the internal compensation circuit for stability which limits its working bandwidth. Frequency response of the compensated Op Amp has slope of −6 dB/octave or −20 dB/decade. Unity gain frequency defines the bandwidth where the Op Amp is able to amplify a signal. If we multiply the gain and frequency at any point, the result is the same, allowing us to use this parameter to select the appropriate Op Amp. It is called Gain-Bandwidth Product, GBW or GBP. The limited open-loop gain introduces a closed-loop gain and phase error.
But we want to optimize our circuits, right?
Common misconceptions about space-grade integrated circuits
Space exploration was always fascinating, and recent developments have reignited the interest to the heights never seen since the last man stood on the Moon. People argue about Mars exploration and features of spaceships as their grandparents would’ve done if the internet existed fifty years ago. I’m an electronics engineer working in the aerospace industry, so I know a thing or two about the technical background of this stuff — and I see that these things aren’t common knowledge, and people often have significantly skewed ideas about the reasons behind many things and decisions. Namely, I’d love to speak of some misconceptions about radiation hardened integrated circuits and the means of protection from radiation-induced damage.
Lab tour: Functional Materials and Devices of Optoelectronics at ITMO University