IBM has not only perfected a method of growing wafer scale graphene as a potential material for the post-silicon era, but has found a way to use it today to dramatically cut the cost of GaN LEDs.
IBM Grows Wafer Scale Graphene – [Link]
by Colin Jeffrey @ gizmag.com:
With LEDs being the preferred long-lasting, low-energy method for replacing less efficient forms of lighting, their uptake has dramatically increased over the past few years. However, despite their luminous outputs having increased steadily over that time, they still fall behind more conventional forms of lighting in terms of brightness. Researchers at Princeton University claim to have come up with a way to change all that by using nanotechnology to increase the output of organic LEDs by 57 percent.
Breakthrough in LED construction increases efficiency by 57 percent - [Link]
Days get shorter but it doesn´t have to be a problem. At purchase of Wago terminal blocks it´s now possible to gain a quality portable LED lamp.
If we want to bring electric energy to same place, we´ll reach for cables. If we want to interconnect them, we´ll reach for Wago 2273 terminal blocks …
Also this way could be characterized well-known push-wire connectors Wago 2273, as they provide practically unrivalled simplicity of usage at interconnecting of wires in installation boxes. Similar situation is also with Wago TopJob S terminal blocks at installations in distribution boxes.
Wago autumn special offer this time brings a portable LED lamp myLUX Professional (230V, 900 lm, 6000K) with a Li-Ion rechargeable battery (exchangeable) – as a gift to the above mentioned connectors and terminal blocks. If you have 230V mains line available, the lamp works on 230VAC and recharges battery at the same time. At a power dropout or in places without electric energy a battery power can be used. Two sets will be available:
Prolong the short days with a Wago autumn special offer - [Link]
I contrast to the very timing-sensitive one-wire protocol of the WS2812, the APA102 uses a standard two wire SPI protocol – one clock line and one data line. Each LED has two inputs and two outputs which can be daisy chained. At the first sight this may seem wasteful, but it has the advantage of being supported by standard microcontroller periphery and it is insensitive to timing variations. Due to the critical timing requirement it is not possible to control the WS2812 from SOCs with multitasking operating systems, such as the Raspberry Pi. This should not be an issue with the APA102. Furthermore, the data can be transferred at an almost arbitrary clock rate. I was able to control the LEDs with 4 MHz SPI clock without any hitch. It appears that the maximum speed is mainly limited by the parasitics of the wiring.
APA102 aka “Superled” - [Link]
xristost blogged about the frequency counter module he made:
First of all I wanted a PIC microcontroller to do the whole job without any additional ICs. Also I wanted to use the the familiar 16F628A, but because one of the portA pins (RA5) can be used only as input I was short of outputs to do the job. Driving 6 digit 7-segment multiplexed display requires 7 + 6 = 13 outputs. The 16F628A has 16 IO pins, two of which are used for the crystal oscillator, one is for the signal input and other one can be used only for input, that leaves us with only 12 useful IO pins. The solution was to drive one of the common cathodes with a transistor, which opens when all other digits are switched off.
Frequency counter with PIC16F628A - [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]
by Martin Jagelka , Martin Daricek & Martin Donoval :
Continuous monitoring of heart activity permits measurement of heart rate variability (HRV), a basic parameter of heart health and other diseases.
This Design Idea is a new design of pulse oximetry that excels in its simplicity and functionality. Due to its capabilities, it can be used as a standalone device, able to monitor heart rate and oxygen saturation.
The core of the system is composed of the ultra-bright red LED (KA-3528SURC), infrared LED (VSMB3940X01-GS08), and a photodiode (VBP104SR) sensitive to both wavelengths of light at the same level.
Simple pulse oximetry for wearable monitor - [Link]
by Jose Daniel Herrera:
Here I present another project based on a addressable LEDs strip, based on WS2812b leds.
It consists of an ‘electronic’ candle, which lets you select set colors, adjust the intensity, and have different effects like rainbow, fade and fire. The project arose from the purchase of an IKEA lantern model BORBY … the idea was to replace a candle of considerable size, for something more … modern.
Candle with remote control and Arduino Pro Mini - [Link]
by Marian Stofka:
Standard optocoupler speed is limited mainly by the relatively slow response of the phototransistor. This Design Idea adds components to the LED drive side to speed things up.
R1 is the original LED resistor, as used before the extra circuitry was added. Here however, its value can be higher, as the turn-on speed is determined mainly by the added circuit. You can thus save power, and also drive the LED with a less powerful driver.
Optocoupler speed-up also reduces power consumption - [Link]