In this video Craig demonstrates his custom DIY RFID smart lock project:
The goal of this project was to design an inexpensive rfid door lock which could be opened via smart phone, and have all activity logged w/o utilizing any 3rd party servers or cloud hosting.
Custom DIY RFID smart lock – [Link]
The LT®8570 and LT8570-1 are PWM DC/DC converters. The LT8570 contains a 0.5A, 65V power switch, while the LT8570-1 contains a 0.25A, 65V power switch. The LT8570 and LT8570-1 can be configured as either a boost, SEPIC or inverting converter.
The LT8570/LT8570-1 have an adjustable oscillator, set by a resistor from the RT pin to ground. Additionally, the LT8570/LT8570-1 can be synchronized to an external clock. The switching frequency of the part may be free running or synchronized, and can be set between 200kHz and 1.5MHz.
LT8570 – Boost/SEPIC/Inverting DC/DC Converter with 65V Switch, Soft-Start and Synchronization – [Link]
After my initial PCB success with Maker Studio, I uploaded the design files to three more board houses. I had planned to try four or five more, but I started to get the impression that many of the China-based sources used the same fab house, so I stopped at three.
Elecrow’s basic board fab service supplies 5 or 10 PCBs for $11.90, with a basic international shipping cost of around $7 for 5 boards. Although I haven’t been paying close attention to delivery time for these reviews (too many variables), I will say that Elecrow was significantly slower than the other three sources.
Quick-Turn PCB shop review project: Elecrow – [Link]
Microchip Technology Inc., has announced the first in a series of modules for the LoRa technology low-data-rate wireless networking standard. The system is designed to allow Internet of Things (IoT) and Machine-to-Machine (M2M) wireless communication offering a range of more than 10 miles (suburban), a battery life of greater than 10 years, and the ability to connect millions of wireless sensor nodes to LoRa technology gateways. The 433/868 MHz RN2483 is a European R&TTE Directive Assessed Radio Module measuring 17.8 x 26.3 x 3 mm and with 14 GPIOs to provide connections and control for a large number of sensors and actuators.
The RN2483 is also supplied with the LoRaWAN™ protocol stack, allowing connection with the LoRa Alliance infrastructure—including both privately managed local area networks (LANs) and telecom-operated public networks—to create Low Power Wide Area Networks (LPWANs) with nationwide coverage. This stack integration also enables the module to be used with any microcontroller with a UART interface. The RN2483 also uses Microchip’s simple ASCII command interface for easy configuration and control.
Microchip LoRa Network Module – [Link]
Just a bit of fun…I try use an oscilloscope to measure / calculate the speed of sound. I also conduct a hearing test during the video.
Measuring the Speed of Sound with an Oscilloscope – [Link]
A look inside Flir’s Lepton thermal imaging sensor.
Flir Lepton extreme teardown – [Link]
What’s inside Keysight’s new 34470A 7 1/2 digit Truevolt bench multimeter?
What are the PCB changes from the 34461A?
What voltage reference does it use to get 16ppm nominal accuracy?
EEVblog #723 – Keysight 34470A 7.5 Digit Multimeter Teardown – [Link]
The charging system for a portable device is not always given a high priority in design but it can have a major role in the battery life of the system and, properly optimized, can allow the use of a smaller battery pack than otherwise would be needed. Not only are compact battery-management controllers needed, but intelligence also needs to be deployed tactically to allow the power system to be correctly optimized. This article will look at the needs of the Li-ion chemistry in terms of charging and what techniques can be used to maximize energy delivery and storage and summarize key solutions available for that purpose.
Lithium-Ion Batteries Call for Multi-Cycle Support to Maximize Uptime – [Link]
by R. Colin Johnson @ eetimes.com:
Living beating hearts on-a-chip were recently created from pluripotent stem cells discovered by 2010 Kyoto Prize Winner, Shinya Yamanaka. Bioengineers at the University of Berkeley aim to create all of the human organs on-a-chip then connect them with micro-fluidic channels to create a complete human-being on-a-wafer.
“We have learned how to derive almost any type of human tissue from skin stem cells as was first discovered by Yamanaka,” professor Kevin Healy told EE Times. “Our initial application is drug screening without having to use animals, but putting organs-on-a-chip using the stem cells of the patient could help with genetic diseases as well.”
Heart On-A-Chip Beats – Microbots put all organs on-a-chip – [Link]
by Petre Petrov @ electronicdesign.com:
The bipolar NE555 timer IC is widely used in inductorless dc-dc converters, most frequently in doubling and inverting converters. However, another very popular IC, the LM386 audio amplifier, may be a better solution in this application. Note that the results also depend on the specific manufacturer of these multisourced ICs and on the quality of the related components. (We will use only Schottky diodes, to reduce the voltage losses to the minimum.)
Comparing the NE555 Timer and LM386 Amplifier as Inductorless DC-DC Converters – [Link]