How boost converters work and how to build a 50W adjustable boost converter circuit.
DC-DC Boost converter tutorial - [Link]
by w2aew @ yoututbe.com
Op amp gain-BW product and slew rate limiting are defined, discussed and demonstrated on the bench. This discussion applies to the majority of general purpose op amps on the market – as most op amps are internally compensated with a single dominant pole. High speed op amps, unconditionally stable op amps, non-unity gain stable op amps, high power opamps, etc. may not follow these characteristics because they are often compensated differently in their design. An LM358N is used for the example circuit. Other popular op amps like the LM741, etc. will behave in a similar way. Sometimes the slew rate limit of a device will be the dominant factor in determining the bandwidth, and other times the gain-bandwidth product will determine the resulting frequency response. The video demonstrates why this happens.
Basics of Op Amp Gain Bandwidth Product and Slew Rate Limit - [Link]
We all know lithium-ion batteries need careful monitoring to prevent over-charging and ensure cell temperature remains within limits. We all thought we knew the best way to replace the charge as well: trickle charge, take it nice and gentle to keep the cell temperature down and prolong cell life. Turns out we may have got that last one wrong! New findings published in the Nature Materials Journal by a team of researchers at Stanford University indicate that by tweaking the battery design it may be possible to get faster charge/discharge rates and also increase the number of charge cycles.
Better lithium-ion Charging - [Link]
A press release from the University of Southern California describes a novel transmission technique which can achieve very high data rates. The research led by Alan Willner of the USC Viterbi School of Engineering does not use a single carrier to send information but instead combines independent radio beams using a ‘spiral phase plate’ that twists each radio beam into a unique and orthogonal DNA-like helical shape. The receiver untwists the beams and recovers the different data streams. “Not only is this a way to transmit multiple spatially collocated radio data streams through a single aperture, it is also one of the fastest data transmission via radio waves that has been demonstrated,” Willner said.
Twisted RF beams achieve 32 GB/s - [Link]
Ondřej Karas of DoItWireless writes:
If You are interested in LED driving through RF, this article would be interesting for you. I tested own PCA9634 breakout board for this chip and wrote simple low level driver for IQRF TR-52D module. Next week, I am going to publish PC application for comfortable operation with that.
Wireless LED driver with PCA9634 - [Link]
Peter Jakab has written a new article on how to adapt character LCD modules for 3 volt operation.
Generic character LCD modules contain an industry standard HD44780 compatible controller, which can operate down at 3 volts. But the modules are usually specified to work only at 5 volts, unless you choose a specific one designed for 3V operation. It is possible and simple to adapt the 5V modules to work on 3 volts.
Getting character LCDs to work at 3 volts - [Link]
HOPERF modules enable to gain a wireless data transfer or remote control of devices simply and without excessive costs.
A company, which specializes over a quarter of century on a given segment usually has experience and production capacities to develop and produce quality components. This is also a case of company HOPERF Micro-electronics and moreover – thanks to high production capacities the prices of their products are very attractive. HOPERF produces RF chips themselves, as well as read-made RF modules usable for virtually any application requiring a wireless control or data transfer, for example: remote keyless entry (RKE), control, security systems, telemetry, voice and data communication, control of processes and many others.
HOPERF modules offer besides a great price also a very high flexibility of usage. In contrast to many “fix-set” modules, RF modules HOPERF usually offer very wide possibilities to dynamically adjust many parameters, like for example: FSK/ OOK/ ASK modulation, possibility to work in a wide frequency range including free ISM bands 315, 433, 868 and 915MHz, while all main RF communication parameters are programmable.
In our stock can be found for example:
- RFM65CW-433S2 and RFM65CW-868S2 – 433/868 MHz FSK receivers. RFM65CW offers a unique possibility to use narrow-band and also wide-band communication modes. RFM65CW is optimized for a low power consumption while maintaining high sensitivity.
- RFM68CW-433S2 and RFM68CW-868S2 – 433/868 MHz FSK transmitters. It can be used without configuration from an MCU. However, in connection with MCU, it´s possible to change many parameters including output power, modulation format and a working channel.
- RFM73-S – 2,4 GHz transceiver, including a high power +20dBm version RFM73P-S2.
- RFM83C-433S1 – sophisticated 433 MHz ASK/OOK receiver including a version for low voltages RFM83CL-433S operating already from 2.1V
- RFM85W-433D – 433 MHz ASK transmitter. Excellent features and simple usage. Specially designed for remote control, car-alarms etc. working on 433.92 MHz.
- RFM12B-868S2P – multichannel 868 MHz FSK transceiver. RFM12B contains integrated functions of a digital data processing like: data filtering, clock recovery, data pattern recognition, integrated FIFO and TX data register. RFM12B enables to provide a clock for microcontroller.
HOPERF – universal RF modules for surprising prices - [Link]
Electro18 posted a tutorial on how to make a portable digital optical tachometer using an Arduino Uno, an instructable here:
A tachometer is a device used to measure the RPM or Revolutions Per Minute of any rotating body. Tachometers can be contact based or non-contact ones. The non-contact or contact-less optical tachometers usually use laser or Infrared beam to monitor the rotation of any body. This is done by calculating time taken for one rotation.
It can measure RPM over 20k
Sensor range extends upto 7~8 cm
Displays Maximum RPM
Measure RPM – DIY portable digital tachometer - [Link]
An inexpensive single board computer which connects to a composite video monitor, keyboard, and SD card by Jack Eisenmann:
I created the DUO Light as a low cost platform for hobbyists to create fun and useful software. The DUO Light is ideal for anyone who wants a low power computer with video output and keyboard input.
The DUO Light is a hybrid of the Arduino UNO and the Raspberry Pi, but costs less than each. At the heart of the DUO Light is the ATMega328, the same microcontroller as in the Arduino UNO. This chip connects to a variety of peripheral devices, including a composite video monitor and SD card (in a similar fashion to the Raspberry Pi), PS/2 keyboard, and general purpose I/O ports. The second chip onboard is a 64 KB serial SRAM, which also connects to the ATMega328.
DUO Light Computer - [Link]
Free PCB Design Tool – CircuitMaker powered by Altium.
You deserve something better. You’re part of the electronics maker and hobbyist community, and you’re coming up with amazingly cool and innovative things every day. We think you deserve better design tools, made specifically for you, to turn those great ideas into reality. That’s why we’re developing CircuitMaker.
CircuitMaker will be a free PCB design tool powered by Altium. With a streamlined interface and powerful engine to boot, you’ll never have to worry about your software holding you back. This will be a free design tool unlike anything you’ve seen before.
Free PCB Design Tool – CircuitMaker powered by Altium - [Link]