Sam Davis writes:
Individual solar-panel systems produce dc power for remote applications while also storing energy in a rechargeable battery supported by a battery-charger IC.
In non-utility grid applications solar panels produce dc power for emergency roadside telephones, navigation buoys, and other remote loads. Virtually all 12-V-system solar panels comprise a series of photovoltaic cells that have a maximum output power of less than 25 W. In producing this power the solar-panel system uses a battery to provide power when the panel is “dark.” The rechargeable battery can supply power for long periods of time, requiring a charger that can properly operate a solar panel.
Meeting this need is Linear Technology’s LT3652 monolithic buck-charger IC, which operates with a single solar panel. The IC uses average-current-mode control-loop architecture to provide constant current/constant voltage (CC/CV) charge characteristics with a programmable charge current. The charger can be programmed to produce a 14.4-V float voltage. Housed in a 3- × 3-mm DFN-12 package, the IC can charge a variety of battery configurations, including up to three Li-Ion/Polymer cells in series, up to four Lithium Iron Phosphate (LiFePO4) cells in series, and sealed lead-acid batteries up to 14.4 V.
Power-Tracking Battery-Charger IC Supports Solar-Power Systems - [Link]
If you´re searching for an RF communication module with a long range, you´re on the right address. More precisely said – 40 km at line-of-sight outdoor, or 550m indoor.
XBee technology enables to transfer data from various sources, mainly in industry – for example data from various sensors, controlling of technology and similar. XBee-PRO 868 from DIGI International (Maxstream) uses SRD G3 868 MHz band (869,525 MHz) and has a software selectable output power in the 1 – 315mW range.
Relatively high maximum output power provides to the module a very long range. This enables to use it in applications with long distances between particular points. XBee_PRO can be connected to your application via a standard 3.3V CMOS UART with 1.2 to 230.4 Kbps data rate. Various XBee modules from Digi International feature common footprint, that´s why they´re mutually exchangeable this adaptable to your application requirements. XBee-PRO 868 features 128 bit AES encryption and a 64 bitovou adress (network ID). They are usable for Point-to-Multipoint/Star or also Peer-to-peer topologies. An advantage is also an easy use – no further configuration is necessary.
Available are multiple versions, type XBP08-DPSIT-024 has an RPSMA connector. Thanks to it, the module can be connected to various antennas.
With XBee-PRO 868 you have 40 km within reach - [Link]
After a big response on the CL20M45 current limiting diode, we decided to add the type CL40M45 with a double nominal current. That´s why you´re free to choose from 2 types, and thus add a bigger variability to your LED applications.
In the article „Drive LEDs from 230V mains more simply and reliably“ we described to you the principle and usage of current limiting diodes (CLD) in detail. A new type in our offer – CL40M45 features a nominal current of up to 40 mA. Other specification is identical to the type CL20M45, especially Umax 45V and Ptot 1W.
By a simple replacement of CL20 for CL40 we can reach a significant change of a current flowing through LED diodes in the application. This can be convenient for example at designing a device with an adoptable power – at the production, it is possible to choose the type CL20M45 or CL40M45 – depending on customer´s requirements (higher light output or power saving at a lower light output). At the same time, this provides a possibility to reach a wide current range at parallel connection of various CLDs, without a need to modify the PCB.
As it is clear from the first sight, a higher maximum current through a CLD also means a higher heat generated on the chip itself. Both types feature max. power dissipation of 1W, that´s why it is necessary to take this fact into account at the circuit design. While at the CL20M45 it is possible to operate with the continuous current of 20mA up to a maximum operating voltage of 45V (P=0,02Ax45V=0,9W), at the CL40M45 the thermal loss (1,8W) would already be too high. That´s why the maximum continuous operating voltage on the CL40M45 is approx. 25V and the „reserve“ up to 45V is usable for elimination of spikes or disturbances in power supply and similar. For further increasing of durability and reliability, it can be useful to design a PCB with enlarged copper pads serving for trouble-free heat dissipation from the CLD.
LED diodes from the 230V mains on 2 ways - [Link]
After discovering how cool RGB LED strips are, I decided to make a bandwidth monitor for the Internet connection at our place. Since there are many users active on the same connection there’s bound to be conflicts where someone is gaming and another is downloading, causing the ping to fluctuate (even with QoS HTB-init set up).
Using RGB LED Strips to Monitor - [Link]
Parallax has released Propeller GCC Beta!
Welcome to the beta test of Parallax’s Propeller GCC compiler for the P8X32A Propeller chip. The Propeller GCC Compiler tool-chain is an open-source, multi-OS, and multi-lingual compiler that targets the Parallax Propeller’s unique multicore architecture. Parallax has hired industry experts to develop all aspects of the toolchain, including the creation of a new development environment that simplifies writing code, compilation, and downloading to a Propeller board. The C and C++ compiler tools provide a significant benefit to Parallax customers who use our Propeller multicore processor. Using the Large Memory Model (LMM) and Extended Memory Model (XMM) gives the developer the ability to write C or C++ programs that run faster than Spin or exceed Spin’s 32 KB program size limit, respectively. Additionally, Parallax will be publishing tutorials on learn.parallax.com to provide experience to new developers interested in learning how to develop embedded applications in C or C++. All of this effort will immediately roll into developing compilation tools for Parallax Semiconductor’s long awaited Propeller 2 when it is released.
Parallax Releases Propeller GCC Beta - [Link]
The Kinetis L Microcontroller board from Freescale. The board features a Cortex-M0+ ARM processor, a suspiciously familiar minty-fresh board silhouette, and headers that remind me of summers in Ivrea. From EDA360: [via]
There are two major reasons for reading this blog post:
A 32-bit microcontroller that sells for as little as $0.49 in 10K quantities and consumes 50µA/MHz
A $12.95 development board to be available late in September
These are two of the salient attributes of the Freescale Kinetis L microcontroller, previewed at Design West in San Jose back in March and now announced at the Freescale Technology Forum in San Antonia with alpha samples shipping. The target for this product is the vast sea of products and applications that currently incorporate 8- and 16-bit microcontrollers—mainly for reasons of legacy code, legacy familiarity, and cost. It will take a compelling product to hurdle these barriers and the low prices for the Kinetis L silicon and development board will help to jump those hurdles.
Freescale Announces $13 ARM Cortex-M0+ Microcontroller Board - [Link]
Schurter 5500.0655.1 line filter will enable it to you and provides an universal usage, independent on the type of the of the inlet power socket used in your device.
It is necessary to use an input line filter in almost every device. At its choosing, you have a possibility to use a filter combined with an input line socket , or a standalone, most often designed for PCB mounting.
Thanks to a big amount of various electric devices with a non-linear power consumption, the line voltage sinusoid is far distant from a clean form found in books of mathematics. Despite still more stringent EMI and EMC regulations, it is necessary to use line filters – also thanks to the fact, that modern digital circuits with a very low power consumption are potentially more sensitive for disturbances. A similar situation is at analog circuits, where more sensitive circuits are used (amplifiers, AD and DA converters, …). A usage of a filter brings two benefits – a better protection of a device from disturbances and also prevents a noise leakage from your device to a mains line.
A novelty in our portfolio is the Schurter 5500.0655.1. line filter for PCB mounting. Advantage of the PCB version is, that it doesn´t require a space on your device´s rear panel. With a maximum current of 6A, it is suitable even for relatively powerful devices. In the Schurter 5500.0xxx datasheet can be found detailed graphs about the filter attenuation in a common, as well as differential mode. For highest demands regarding EMC, it is possible to equip the filter with a metal shield.
Afford to your devices an undisturbed operation - [Link]
Rajendra Bhatta writes:
The 12F series of PIC microcontrollers are handy little 8-pin devices designed for small embedded applications that do not require too many I/O resources, and where small size is advantageous. These applications include a wide range of everyday products such as hair dryers, electric toothbrushes, rice cookers, vacuum cleaners, coffee makers, and blenders. Despite their small size, the PIC12F series microcontrollers offer interesting features including wide operating voltage, internal programmable oscillator, 4 channels of 10-bit ADC, on-board EEPROM memory, on-chip voltage reference, multiple communication peripherals (UART, SPI, and I2C), PWM, and more. The following project board is designed for fast and easy development of standalone applications using PIC12F microcontrollers. It features on-board regulated +5V power supply, header connectors to access I/O pins, ICSP header for programming, a reset circuit, and small prototyping area for placing additional components.
PIC12F microcontroller project board - [Link]
Publitek European Ed writes:
Daylight harvesting is becoming increasingly important in the design and implementation of commercial lighting systems. Being able to integrate the natural light from windows with flexible, controllable sources of lighting helps improve the work environment and cut energy bills.
Being able to have closer control of the lighting systems in a commercial environment is a key element to this strategy and energy harvesting can play an important role. Being able to have flexible placement of control pads for a commercial lighting system is an important requirement as office space is regularly reconfigured as existing clients grow and change their requirements and new clients have new requirements.
Smart Lighting in the Enterprise - [Link]
Jack Shandle writes:
LED-based lighting has many advantages including a small footprint, exceptionally long lifetimes and excellent lighting efficacy in lumens per watt. As LEDs have become popular, the challenges of designing with them have become more evident – with thermal management topping the list.
The challenge begins with the source itself. High-powered LEDs do not generate infrared radiation, which is the primary way competing light sources dissipate energy that is not visible light. Instead, 75 to 85 percent of energy used to drive an LED is converted to heat, compared to 42 percent for a typical linear fluorescent, 37 percent for a metal halide bulb, and only 19 percent for an incandescent light source. In LED-based system designs, this heat must be conducted from the LED die to heat sinks, the circuit board, housings or luminaires. In addition, power dissipation in other parts of the system, such as the power supply, must be minimized.
ABCs of LED Thermal Management - [Link]