A battery charger is a device used to energize a rechargeable battery by driving an electric current through it. The charging protocol depends on the size and type of the battery being charged. Some battery types have high tolerance for overcharging and can be recharged by connection to a constant voltage source or a constant current source; simple chargers of this type require manual disconnection at the end of the charge cycle, or may have a timer to cut off charging current at a fixed time.
The MCP1631HV multi-chemistry reference design board is used to charge one, two, three or four NiMH batteries or one or two cell Li-Ion batteries. The board uses the MCP1631HV high speed analog PWM and PIC16F883 to generate the charge algorithm for NiMH, NiCd or Li-Ion batteries. It is used to evaluate Microchip’s MCP1631HV in a SEPIC power converter application. As provided, it is user programmable using on board pushes buttons. The board can charge NiMH, NiCd or Li-Ion batteries. It provides a constant current charge (Ni based chemistry) and constant current / constant voltage (Li-Ion) with preconditioning, cell temperature monitoring (Ni based) and battery pack fault monitoring. Also, the charger provides a status or fault indication. It automatically detects the insertion or removal of a battery pack.
The MCP1631 multi-chemistry battery charger reference design is a complete stand-alone constant current battery charger for NiMH, NiCd or Li-Ion battery packs. When charging NiMH or NiCd batteries the reference design is capable of charging one, two, three or four batteries connected in series. If Li-Ion chemistry is selected, the board is capable of charging one or two series batteries. This board utilizes Microchip’s MCP1631HV (high-speed PIC® MCU PWM TSSOP-20). The input voltage range for the demo board is 5.3V to 16V.
Multi-Chemistry Battery Charger from Microchip - [Link]
In a bid to encourage greater use of TI’s Programmable Real-time Unit (PRU) built into the Sitara AM335x and AM437x family of devices which power the BeagleBone Black development board Texas have announced the PRU cape. The PRU is made up of dual 200 MHz coprocessors, implementing a low-latency subsystem optimized for deterministic, real-time processing allowing direct access to I/Os. It would be fair to say that this capability is seldom used by BeagleBone developers because it has been found to be complex to program.
The Texas PRU Cape - [Link]
Headless Ghost is a display emulator (dummy plug) that fits discreetly in to a HDMI socket.
It fixes a problem you probably didn’t even know you had – unlocking the full potential of your graphics card hardware.
By simulating the presence of an attached display, Headless Ghost allows you to use all of the power and available resolutions locked away inside your graphics hardware, which might otherwise be disabled when there is no screen available.
Headless Ghost – HDMI emulator - [Link]
Linear Technology Corporation has announced the LTC2983 high performance digital temperature measurement IC. The IC is a single chip solution to temperature sensor interfacing; it has 20 input channels for sensor connection and each input can be assigned the characteristics appropriate to the sensor used. This includes 8 standard thermocouple types, 8 RTDs, 8 thermister profiles and an external diode; if you are using a custom sensor you can also specify a custom table.
In addition to the impressive sensor capability the IC measures temperature with an accuracy of 0.1°C and a resolution of 0.001°C. The LTC2983 allows direct interfacing to ground referenced sensors without the need for level shifters, negative supply voltages, or external amplifiers. All signals are buffered and simultaneously digitized with three high-accuracy, 24-bit ΔΣ ADC’s, driven by an internal 10 ppm/°C (maximum) reference.
High Accuracy Universal Temperature Sensor IC - [Link]
This project is an audio amplifier based on TDA2050 and LM1875.
This is not an ordinary project, but an attempt to make a PCB that is suitable for TDA2050 and LM1875 and has all the necessary circuitry on board – power supply, speaker protection, delayed turn-on and fast turn-off. This is achieved using the convenient uPC1237 IC.
TDA2050 and LM1875 are pin to pin compatible, the differences in their schematics are the values of a couple resistors and one capacitor. All this allows to make an universal circuit board, suitable for any of these two ICs.
Audio Power Amplifier with TDA2050 - [Link]
by Digi-Key Corporation:
The Cree LMH2 LED Module provides unparalleled efficacy and light quality in a fully integrated module. Utilizing Cree’s True White Technology, the LMH2 provides beautiful 90 plus CRI lights in 4000 Kelvin, 3500 Kelvin, 3000 Kelvin, and 2700 Kelvin color temperatures. In addition, the LMH2 delivers 97 LPW efficacy across all CCT and lumen options. There are two lens options. The flat lens provides an 82 Degree Beam Angle while the Dome lens provides a 100 Degree Beam Angle. In addition, there is a Unique Driver Compatibility Program that provides a list of tested and recommended drivers for the LMH2. There is also a 5-year warranty on the module, even for those utilizing a third party driver. Finally, the aluminum housing provides tremendous thermal design flexibility.
Cree LMH2 LED Module Versus Traditional CFL Options - [Link]
RGB LED disco light is a simple project designed around PIC16F72 microcontroller.
This firmware is a RGB driver, as name suggests it is used to derive or light red, green and blue LEDs in particular fashion. Its main feature is the pattern shown on LEDs. It is quite difficult to describe pattern in words but we want to specify that first it will derive red then green then blue three times and then a particular pattern is shown on LEDs and again the three LEDs light.
RGB LED Disco Lights - [Link]
by amandaghassaei @ instructables.com:
I’m working on a project that requires full orientation information, so I built an Inertial Measurement Unit from scratch. I really like the 9DOF IMU board that Sparkfun makes – the calibration code that comes with it is fantastic – but I wanted to redesign the board so that it could be made at a much lower price using a single-sided PCB mill. I think the electronics come out to about $20 for this project. All the code, schematics, and PCB milling files are up on github (click the cloud-shaped button to download).
“9 Degrees of Freedom” IMU - [Link]
by df99 @ instructables.com:
This is an OLED clock I built using an Arduino Micro, a tiny OLED 128×64 display using the SSD1306 controller and I2C interface, and a precision DS3231-based real-time clock module with rechargeable battery backup. It features a menu system for setting the RTC (no serial port or USB required)
DS3231 OLED clock with 2-button menu setting and temperature display - [Link]
by willseph @ imgur.com:
The web interface allows me to change the settings on my thermostat remotely, such as the set temperature range compressor and fan modes, as well as view any warning messages that may be reported.
It’s not exactly beautiful, but I’m a function-over-fashion person. The Raspberry Pi is in the middle, white power cable running down and a GPIO rainbow ribbon cord heading up to the relay module under the real thermostat.
Homemade Raspberry Pi smart thermostat - [Link]