Page 970 – Electronics-Lab.com

Circuit adds foldback-current protection

Posted on 31 July, 2015 by mixos

by Rafael Garcia-Gil @ edn.com:

For many applications that require power-supply currents of a few amperes or less, three-terminal adjustable-output linear voltage regulators, such as National Semiconductor’s LM317, offer ease of use, low cost, and full on-chip overload protection. The addition of a few components can provide a three-terminal regulator with high-speed short-circuit current limiting for improved reliability. The current limiter protects the regulator from damage by holding the maximum output current at a constant level, IMAX, that doesn’t damage the regulator (Reference 1).

Circuit adds foldback-current protection – [Link]

Use an LM317 as 0 to 3V adjustable regulator

Posted on 31 July, 2015 by mixos

by Vladimir Rentyuk @ edn.com:

Most engineers know that they can use an inexpensive, three-terminal adjustable regulator, such as Fairchild Semiconductor’s LM317, as an adjustable regulator to only some necessary value of voltage, such as 36 or 3V. This value cannot be less than 1.25V without employing other approaches, however. The devices’ inner reference voltage is 1.25V, and their output voltage accordingly cannot be less than this value without potential bias (Reference 1). One way to solve this problem is to use a reference-voltage source based on two diodes (Reference 2).

Use an LM317 as 0 to 3V adjustable regulator – [Link]

Making the new silicon: Gallium nitride electronics could drastically cut energy usage

Posted on 31 July, 201531 July, 2015 by mixos

by Rob Matheson @ phys.org:

An exotic material called gallium nitride (GaN) is poised to become the next semiconductor for power electronics, enabling much higher efficiency than silicon.

In 2013, the Department of Energy (DOE) dedicated approximately half of a $140 million research institute for power electronics to GaN research, citing its potential to reduce worldwide energy consumption. Now MIT spinout Cambridge Electronics Inc. (CEI) has announced a line of GaN transistors and power electronic circuits that promise to cut energy usage in data centers, electric cars, and consumer devices by 10 to 20 percent worldwide by 2025.

Power electronics is a ubiquitous technology used to convert electricity to higher or lower voltages and different currents—such as in a laptop’s power adapter, or in electric substations that convert voltages and distribute electricity to consumers. Many of these power-electronics systems rely on silicon transistors that switch on and off to regulate voltage but, due to speed and resistance constraints, waste energy as heat.

Making the new silicon: Gallium nitride electronics could drastically cut energy usage – [Link]

WIFI Mains Power Dimmer / Switch

Posted on 31 July, 2015 by mixos

MAINS Power Dimmer / Switch Module project by Tracker J:

Now it’s about time to talk also about what many of you has asked for: DIMMING!
It’s a total different story, little bit complicated but, as you will see, not so hard to understand.

General considerations:
There are several types of dimmers generally available. These are used for resistive, and inductive loads, such as incandescent,cold cathode and low voltage (inductive) lamp sources. Note that not all electronic transformers used for low voltage lamps are suitable for dimming by Triac or Thyristors dimmers. In case of Thyristors you need 2 of them as Thyristor is a Unidirectional device and because AC power flows in both directions!

WIFI Mains Power Dimmer / Switch – [Link]

Have you ever seen a fan resistant to dust and water?

Posted on 30 July, 2015 by mixos

New series of Sunon fans with IP68 protection brings reliability even to conditions, where a usual fan doesn´t withstand too long…

Still more noise and vibrations and in extreme case even a total malfunction – this is a typical “end” of the fan after a long-time operation in a dusty or corrosive environment. In a usual dry and relatively clean environment, this scenario is not that dramatic and high-quality fans hold on to work for many years without problems. However, it can be also said, that common industrial environment is quite far from an ideal = clean one.

So, which fan to use?

The first good advice might be to use a quality fan, for example from companies Sunon or EBM-Papst. Company Sunon this time declares, that they shifted a level of lifetime and durability a step higher… They “wrapped” all the motor into a „high-tech“ coating and incorporated a mechanism for automatic dust removal from a motor part.

And the result?

The fan works reliably even after a 60 minute ingress into water and into 1m depth. That´s only a small example demonstrating features of the new series with IP68 protection. New series carry GExxxx or GFxxxx marking and they´re available in three sizes – 80x80x25mm, 80x80x38mm and 90x90x25mm. All types are equipped by two ball bearings.
On stock we have types – GF80251B1-AE9 ( 80×25 12VDC 3,96W 101,9m3/h) and GE80252B1-AE9 ( 80×25 24VDC 4,8W 101,9m3/h). Upon request we´re able to supply you also other types.

Have you ever seen a fan resistant to dust and water? – [Link]

Simple Acoustic Guitar Sound Receiver

Posted on 30 July, 2015 by mixos

This design of acoustic sound receiver features low power operational amplifier. It has rail-to-rail input/output and 0.85mA supply current per amplifier. It uses piezo speaker as its microphone that can be attached to easily due to its size and dimension.

The circuit is comprised of MCP6L91RT-E/OT 10 MHz, 850 µA operational amplifier that is used to amplify the sound signal. The low-pass filter is used to allow low frequency signal to pass while attenuating high frequency signal or above cut-off frequency of the system to prevent distortions and unnecessary signal. The piezo speaker is used as a microphone or a sound receiver in this circuit. Its size and dimensions is well suited for this application.

The circuit is suitable for different types of acoustic guitar. Since it can be attached easily, the old and other traditional instruments can be developed and modified so that it can continue its service even for the digital era. It can be interfaced to different applications which is not limited to musical instrument.

Simple Acoustic Guitar Sound Receiver – [Link]

Seven Segment Display Arduino Thermometer

Posted on 30 July, 2015 by mixos

by Ardumotive_com @ instructables.com:

Today I will show you how to make your own 7 segment – 2 digit – thermometer with Arduino uno and DS18B20 temperature sensor.

I prefer to build my own arduino based circuit by using the ATmega328p uno possessor, but this is optional for you. You can also use breadboard to build it easier 😉

Seven Segment Display Arduino Thermometer – [Link]

Inside the Intel RealSense Gesture Camera

Posted on 30 July, 2015 by mixos

by Sinjin Dixon-Warren @ chipworks.com:

The Intel® RealSense™ gesture camera represents another foray by Intel into the consumer products space. The camera has been incorporated into the Lenovo ThinkPad Yoga 15. Intel disclosed at IDF14 that the device is formed using three components: a conventional color CMOS image sensor camera, an infrared images sensor, an infrared light projector (the main focus of this article), plus an image processor. It can also incorporate a pair of microphones.

Inside the Intel RealSense Gesture Camera – [Link]

Even you switch ecologically?

Posted on 29 July, 2015 by mixos

More exactly, we talk about switching-off a device. Marquardt 1550 Eco Switch enables this extraordinarily easily.

Do you know a situation, when a seemingly usual thing is fact not that usual… Whether it´s a car with a hybrid drive or a lot of devices which we meet every day – usually in every segment can be found something “inconspicuous” but in fact unusual and exquisite. This is exactly the case of the 1550 Eco Switch series.At the first sight – a usual rocker switch of this series is able to switch off a device in a pre-defined time or it can be switched off remotely – by a pulse (4A/250V, 10ms). Both cases result in a physical contacts disconnection, what´s advantageous from a safety point of view (total galvanic isolation and overvoltage protection) as well as from a zero power consumption point of view. In case of a remote-off version a given switch can be controlled also by the controlled device itself (which is powered through this switch). In this case it results to self “cut-off” of a device and it can be switched on again only physically by an operator. A typical example of use can be a safety function of temperature monitoring inside a device which is able to switch off itself in case of a fault.

1550 Eco Switch series can be used not only for power supply line. The contacts reliably switching even small DC voltages enable usage also for transition of various control signals and similar.

Detailed information will provide you the Marquardt 1550 Eco Switch datasheet and Marquardt 1550 versions.

Even you switch ecologically? – [Link]

Making A SMD Reflow Oven

Posted on 29 July, 2015 by mixos

by packetbob @ instructables.com:

I decided to put together a toaster oven and wanted something that could handle large boards and possibly do small production runs. Doing a web search, you will find many options for toaster oven reflow controllers. They range from one-off designs to DIY boards to full kits. A large number of them are Arduino based. Some controllers just allow the oven to plug in (so you don’t need to take the oven apart) while others integrate completely inside the oven (more work but a much better product in the end).

Making A SMD Reflow Oven – [Link]