bogdan @ electrobob.com wanted to know how much heat a heatsink can dissipate so he build a simple setup using a temperature sesnsor and a mcu. He writes:
It’s quite a common problem when building electronics that some components need cooling which is usually done through some sort of heatsink and optional fans. Choosing the right cooling solution can be a difficult task because the real life behavior of the system is hard to predict or model. In my case I have faced the simple question quite a few times: how much heat can a cooling system dissipate? The thermal resistance of a particular heatsink may vary quite a lot depending on the surroundings or it can simply be unknown to start with. The aluminum side wall of an enclosure made me build this thing.
This is why I have made this little device: a thermometer, a transistor and a microcontroller with a simple command line interface. I could have answered my questions in quite a lot of simpler ways, but since I made a simple thermometer not much else is needed to control the transistor when a DAC is available in the microcontroller.
Heatsink Tester - [Link]
What is the actual capacitance of typical breadboard contacts?
It’s not in the datasheet, so Dave decides to measure it. It is well know that breadboards are not suitable for high frequency work due to the stray capacitance between contacts, but how bad is it really?
EEVblog #568 – Solderless Breadboard Capacitance - [Link]
40-meter LIDAR-Lite – optical distance measurement sensor. Fulfills an unmet need for an optical distance measurement sensor to address applications where a very small, low-power, high performance, reduced cost optical ranging sensor is required, such as robotics, UAVs (or drones), and automotive (driverless car features).
The MiniModule 40 is a very small form factor, optical distance measurement sensor capable of measuring out to 40 meters using inexpensive, off-the-shelf, electro-optical components. It delivers the performance of a laser range finder in a much smaller package at a fraction of the cost.
Our sensor technology is ideally suited for any project requiring very compact, low power, high performance distance measurement sensors, such as drones, robots, or unmanned vehicles.
PulsedLight’s novel signal processing technology enables us to offer a low-cost optical distance measurement solution with performance comparable to systems costing hundreds of dollars.
After more than two years of work, we are ready to introduce our technology in the form of the LIDAR-Lite, a very small form factor, optical distance measurement sensor capable of measuring out to 40 meters using inexpensive, off-the-shelf, electro-optical components.
LIDAR-Lite – Optical Distance Measurement Sensors - [Link]
Google have unveiled an example of smart, wearable technology that could in future prove a life-saver for diabetes sufferers. They have succeeded in integrating a tiny glucose sensor and associated circuitry into a soft plastic contact lens.
With the incidents of diabetes growing in the population it is becoming a major problem for health authorities worldwide. To get a reliable blood-glucose reading today’s diabetics regularly suffer the inconvenience of testing a pin prick of blood in a hand-held glucose monitoring unit. The contact lens sensor in development by Google is powered in much the same way as an RFID tag which uses energy induced in a pickup coil from a close-proximity transmitter to send out its ID information. The Google lens sensor has hair-thin aerial elements around the circumference of the lens which pick up a signal produced, presumably from spectacle frames or Google Glass headwear. The signal is sent at one second intervals and is sufficient to power the glucose sensor and return its measurement taken from the tear solution which bathes the eye. [via]
A Contactless Contact Lens - [Link]
From now, it´s even more probable to find the right connector for your application in our store.
After success of so far types of connectors for memory cards and SIM cards, we add to our stock offer many other types of connectors for SIM cards, SD cards, micro SD cards, CF cards, E-SAT, DDR and other from company Attend.We realize that at a development even seaming trifles are important, other pin position etc., which decide whether a given connector is usable or not in your application. That´s why we offer you at some types (SD, micro SD, SIM, …) even several versions of a seemingly same connector. From many types we have in stock initial amounts as yet, but soon we´ll increase this count – depending on your interest.
An interesting alternative to common micro SD connectors is the type 112C-TBAR-R02 with a swiveling holder. The connector is suitable for applications, where an often exchange of SD cards is not supposed, but it is necessary to save space on a PCB or where it´s not possible to insert a memory card from a side.
Similarly interesting is the „2in1“ connector 112G-TA00-R for a micro SD and a SIM card. This connector particularly saves PCB space.
Memory media and data communication without limitations - [Link]
This simple project is a digital thermometer using LM35 sensor and Attiny26 mcu to read the sensor value and display it on the LED display. LM35 output is amplified by 11 so can be read by mcu internal ADC. The hardware design files and firmware source code are available on the project’s page.
The sensor section is composed of LM35, OPA344 and some passive components. The LM35 is a precision temperature sensor that outputs 10mV per °C. Therefore, LM35 will output 0.25V or 250mV if it is measuring 25°C. The OPA344 is an operational amplifier that is configured as non-inverting amplifier with a gain of 11. The gain of OPA344 is set by R15 and R16. The OPA344 is used to multiply the voltage output of LM35 by 11. So, the output of OPA344 is 2.75V if the output of LM35 is 0.25V. R17 and C6 serves as a low pass filter for the output of OPA344. The values for R17 and C6 were arbitrarily chosen but for optimum performance, these values must be carefully chosen.
Simple Attiny26 based LM35 digital thermometer - [Link]
This is a simple 3.3V and 5V dual power supply using LD1117V50 and LD1117V33 low dropout voltage regulators.
I normally use a USB port as power supply for my projects but some ICs need 3.3V instead of 5V. Therefore I decided to build this small dual power supply. Power supply uses two low dropout voltage regulators that provide up to 800mA of output current and come in TO-220 package. LD1117V33 is used for 3.3V and LD1117V50 for 5V. Input voltage is 6V-15V and both regulators can be switched on/off individually.
3.3V and 5V Power Supply - [Link]
Admittance control, movement of goods, tickets for various cultural events and sport matches, travel tickets, parking,… thanks to a permanently lower price and bigger possibilities of RFID cards (tags) the Mifare system (13,56 Mhz) in various variations runs forward even to segment where an older 125 kHz system didn´t suite. Complete RFID solution for a very affordable price, it is a short summary of RFID modules features from company Stronglink, which we already introduced to you in several articles.
Group of modules SL03x – SL030, SL031 and SL032 represents complete OEM RFID modules with antenna integrated on a PCB, intended to be built into an end device. All these three modules support Mifare Mini, Mifare 1k, Mifare 4k, Mifare Plus and Mifare Ultralight. SL032 further supports also the DESFire protocol. SL030 has an I2C communication interface, while the SL031 and SL032 have a UART. Modules are controlled by a set of simple commands, thus an integration into a device should cause no troubles even to less-experienced developers.
Thanks to a close cooperation with a producer, we aim to keep a sufficient amount of STRONGLINK RFID modules in stock.
SL030, 031, 032 … Mifare RFID available for you - [Link]
This article describes how to use infra-red (IR) sensor with Arduino or with a simple OPAMP comparator. Lee Zhi Xian writes:
What is infra-red (IR)? Infra-red is an electromagnetic wave who wavelength is between 0.75 microns to 1000 microns (1 micron = 1µm). Since infra-red is out of visible light range, we can’t really see IR with naked eye. However, there is a method to “see” IR which will be shown later on. Some of the infra-red applications includes night vision, hyperspectral imaging, and communications. We also use IR daily in our TV remote or any device remote.
IR transmitter and receiver can be obtained at low price. Their shape is looks exactly the same as LED. To distinguish between transmitter and receiver, the transmitter always come in clear LED while receiver is black in colour. Other than that, there is also receiver that is used to pick up specific frequency IR, 38kHz. For your information, 38kHz frequency IR is commonly used in remote control.
How to use infra-red (IR) sensor with Arduino - [Link]