Home Blog  





22 Oct 2012

The MAX31855 performs cold-junction compensation and digitizes the signal from a K-, J-, N-, T-, S-, R-, or E-type thermocouple. The data is output in a signed 14-bit, SPI-compatible, read-only format. This converter resolves temperatures to 0.25°C, allows readings as high as +1800°C and as low as -270°C, and exhibits thermocouple accuracy of ±2°C for temperatures ranging from -200°C to +700°C for K-type thermocouples. For full range accuracies and other thermocouple types, see the Thermal Characteristics specifications in the full data sheet.

MAX31855 – Cold-Junction Compensated Thermocouple-to-Digital Converter - [Link]

17 Oct 2012

If we want to obtain a 5V voltage from only 2 NiMH batteries, we´ll face the fact, that the most of common DC/DC circuits doesn´t operate at such a low voltage. LT1304 controller belongs among circuits, which handle this situation without problems and it also provides several extra things.

To obtain 3.3 or 5V from a lower voltage is a typical requirement at battery-powered or portable devices. Naturally, to obtain 5V it is also possible to use 4-5 NiMH cells or 2 Li-Po cells, but then the device is uselessly bigger, heavier and more expensive. The solution is just the usage of a suitable step-up circuit. LT1304 from Linear Technology belongs to “MicroPower” DC/DC step-up circuits operating already from a very small voltage, 1.5V typically. 

Thanks to a very low power consumption (10uA/Shutdown) and a built-in independent low battery detector, it is optimized for usage with batteries. LT1304 needs for its operation only a few external components – 2 capacitors, 1 inductor and 1 diode is all that is necessary to create an operating DC/DC circuit.
LT1304 is available in 3 versions – LT1304VCS8-5, LT1304CS8-3,3 with fixed voltages and LT1304CS8 with adjustable output. Versions with fixed output voltages don´t need a divider in a feedback, what further simplifies a circuit.

Read the rest of this entry »

15 Oct 2012

New multicore DSP devices from the French firm Kalray aim to surpass FPGAs in compute-intensive tasks, such as image and signal processing, 3D augmented reality and industrial automation. The company recently demonstrated the MPPA-256, the first member of their MPPA Manycore family of processors, at CEATEC Japan.

The MPPA-256 is organized as an array of 16 clusters of 16 cores interconnected by a high-bandwidth on-chip network. The proprietary cores are based on a VLIW low-power design and integrate a 32-/64-bit floating point unit. The cores of each cluster share memory, network interfaces, a debug support unit and control logic.

The demo applications at CEATEC include H.264 video encoding of a live 1080p stream from a source with a Serial Digital Interface (SDI), using a parallel implementation of the x264 open-source encoder, an industrial automation demo featuring a set of 17 Programmable Logic Controllers (PLC) running independently and concurrently on the same chip, and a passive sonar application demonstrating the capabilities of the MPPA-256 for complex signal processing tasks. [via]

Massively Parallel DSPs Challenge FPGAs - [Link]

6 Oct 2012

The LTM2883 is a 6-channel SPI/Digital or I2C digital μModule isolator with triple rail regulated power for 3.3V and 5V systems. In industrial systems applications, ground potentials can vary widely, often exceeding the tolerable range, which can interrupt communications or even destroy components. The LTM2883 breaks ground loops by electrically separating communications signals, isolating the logic level interface on each side of an internal inductive isolation barrier that withstands a very large common-mode voltage range up to 2,500VRMS. The LTM2883′s low EMI isolated DC-DC converter powers the communications interface and provides adjustable 5V, +12.5V, and -12.5V supply outputs, ideal for powering data converters in data acquisition systems. With 2,500VRMS of galvanic isolation, onboard secondary power and a communications interface operating at up to 20Mbps, the LTM2883 requires no external components and provides a simple μModule solution for isolated data communications.

LTM2883 – SPI/Digital or I2C μModule Isolator with Adjustable Regulated Power - [Link]


5 Oct 2012

BF245, a JFET transistor produced for many decades by several companies, has joined the list of discontinued components. However an equivalent replacement exists in an SMT package and its name is BF545.

BF245 in a TO-92 package has been one of the first transistors, which were mass-used. That’s why it’s no wonder, that the BF 245 is nowadays familiar to every experienced technician. As a transistor with a very high input resistance (tens of MOhm) and a relativlely low noise, it’s gained a global popularity and served to many beginning technicians at an assembly of their first radio-receivers. There are many other FET transistors on the market nowadays, thus the usage of BF245 is substantially smaller. Moreover, a majority of electronics is produced with SMT components, what probably was one of more reasons why all main producers have discontinued the BF245.

However, BF245 is still an interesting transistor, that’s why it will be henceforward available in a SOT23 SMT package as the BF545. It is available in 3 groups A, B, C – sorted according to IDSS at VGS=0. Directly from our stock are available BF545A, BF545B and BF545C from company NXP (originally Philips). Detailed information can be found in the BF545 datasheet, as well as in the RF Manual document.

BF245 – the legend is leaving, the successor comes - [Link]

29 Sep 2012

The TPS53014 is a single, adaptive on-time D-CAP2 mode synchronous buck controller. The TPS53014 enables system designers to complete the suite of various end equipment’s power bus regulators with cost effective low external component count and low standby current solution. [...]

The device provides convenient and efficient operation with input voltages from 4.5 V to 28 V and output voltage from 0.77 V to 7.0 V.

TPS53014 – Single Synchronous Step-Down Controller for Low Voltage Power Rails - [Link]

27 Sep 2012

SMT components are still more used even in small production batches. That´s why in our portfolio, many components can be found in both versions – THT (through-hole technology) and also SMT.

As the praxis has shown, both Technologies have their stable place in the production of electronics. This is also confirmed by a known fact, that the highest density of components on a single-sided PCB can be reached by a combination of SMT and THT components, when the THT components on the rear side also act as „PCB tracks“.

To many components, which we have in both SMT and THT version, we incorporated a well-known favorite diode 1N4148 in an SMT sod123 package – 1N4148W. It is a universal switching (small signal) diode with a small PN junction capacitancy, thus suitable even for fast circuits. Small leakage current ensures a minimum influence of surrounding circuitry, that´s why the 1N4148 is often used also as a protective diode for protection of digital circuits inputs. Next time, when you´ll design a device with a 1N4148, try to consider, whether an SMT version wouldn´t suit better to you – 1N4148W, LL4148 (miniMelf), TS4148 or other versions.

Favorite diodes 1N4148 -THT but also SMT - [Link]

25 Sep 2012

The DS1339A serial real-time clock (RTC) is a low-power clock/date device with two programmable time-of-day alarms and a programmable square-wave output. Address and data are transferred serially through an I²C bus. The clock/date provides seconds, minutes, hours, day, date, month, and year information. The date at the end of the month is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in either the 24-hour or 12-hour format with AM/PM indicator. The DS1339A has a builtin power-sense circuit that detects power failures and automatically switches to the backup supply, maintaining time, date, and alarm operation.

Low-Current, I²C, Serial Real-Time Clock - [Link]

25 Sep 2012

The LM3463 by Texas Instruments is a six-channel LED driver with dynamic headroom control for high-power applications that accurately drives up to six strings of LEDs. The biggest cost reductions in LEDs today come from improvements in efficacy (fewer LEDs needed for the same light output), and the LM3463 is no exception.

It is the industry’s first wide-input voltage LED driver featuring multiple dimming control modes—PWM input signals, analog-to-PWM input control, or 4-byte data control—to maximize system efficiency and reduces complexity in LED area lighting. The driver targets such bright-light applications as street, high-bay and ceiling lighting. When designers require PWM, the LM3463 is particularly useful as it accepts a simple serial data stream and the LED driver creates the PWM signals internally. It can, therefore, be used with a fairly inexpensive MCU and it easily adjusts brightness. [via]

High-power LED driver features multiple dimming control modes - [Link]

22 Sep 2012

Stephen Evanczuk writes:

Energy-microharvesting applications such as wireless sensor nodes require periodic bursts of power well beyond that available in steady state from most ambient sources. In this respect, supercapacitors offer performance characteristics that are well suited for energy-harvesting environments. By combining supercapacitors with appropriate power and charge management circuitry, and using specialized devices from manufacturers including Linear Technology, Maxim Integrated Products, and Texas Instruments, engineers can exploit microharvesting techniques in applications with demanding peak power requirements.

Power Management ICs Simplify Integration of Supercapacitors in Energy Microharvesting Designs - [Link]



 
 
 

 

 

 

Search Site | Advertising | Contact Us
Elektrotekno.com | Free Schematics Search Engine | Electronic Kits