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Protecting sensitive electronic circuitry from voltage transients is an essential part of any system be it automotive, industrial, avionics or even battery-powered consumer applications. Linear Technology offers a wide variety of solutions for these applications with its surge stopper family. The LTC®4366 is the new exciting member of this surge stopper family.

 

The non-synchronous flyback topology is widely used in isolated power supplies ranging from sub watt power levels to tens of watts. With more green-mode standards emerging around the world, improving light load efficiency and reducing no-load input standby current are more demanding than ever. Unfortunately, the traditional isolated power supplies using optocouplers can no longer achieve the performance requested

 

16kW-hr battery packs made from lithium ion cells are powering electric vehicles and storing grid energy. Measurement ICs like the LTC®6804 are used to extend the life and ensure the safety of the pack. The accuracy of the measurement IC can influence the cost of the system.

 

The digital power supply market has achieved rapid progress in the recent years. Easy configuration, accurate telemetry, convenient fault analysis and reliability are the trends for the modern digital power supply, which are all provided by Linear's new digital power controller, the LTC3883.

 

Bandwidth has become more precious than gold. As we push more and more data wirelessly through our smartphones, tablets, GPS, and video players, the spectrum has become more crowded. Increasingly complex and efficient modulation schemes allow us to carry more MBits/mHz through the air. However, the key to these demanding schemes is a high fidelity signal path. Achieving high linearity and low noise while dissipating a minimum of power are keys to achieving these increased data rates within a limited spectrum and power budget. Similarly, components with built-in ease-of-use and guaranteed specifications are keys to quick, painless design cycles.

 

Linear Technology's LTM4620 uses a proprietary lead frame design to package high power regulators into a very small form factor with effective thermal conduction through the top and bottom of the µmodule product. The device can be connected in parallel to support higher current applications with very accurate current sharing between the channels.

 

 

The zero-IF receiver architecture gains popularity in wireless applications because of its suitability to demodulate very wideband RF signals. This capability is important in digital pre-distortion (DPD) transmitters. Realization of sufficient dynamic range is commonly known to be a major issue of zero-IF architectures. DC offsets and second-order intermodulation products are both co-located in frequency with the signal of interest and therewith reduce the receiver sensitivity.

 

 

The LT®8610 step-down regulator integrates key high performance features in one compact IC. It offers synchronous rectification, for efficiencies up to 96%. The low quiescent current of 2.5µA extends battery life and saves extra circuitry. High speed switching minimizes board space and helps avoid EMI problems. A low dropout of 200mV at 1A load allows wide VIN range. The LT8610 is a great choice for many step-down applications requiring high input voltages up to 42V and load currents up to 2.5A.

 

 

Due to the high cost and inflexibility of isolated DC/DC converter modules, many designers are choosing to implement a discrete design that is better matched to their application. In particular, the forward converter with active clamp reset has been widely used in custom supplies because of its excellent efficiency and reduced component stress. While the active clamp reset technique has advantages, it also introduces performance limitations and potential reliability concerns that have limited the scope of its use.

 

 

 

Successive Approximation Register Analog-to-Digital Converters (SAR ADCs) are key components in instrumentation, industrial control, and test equipment applications. The accuracy, noise and speed of the SAR ADC often determine the overall system performance. In this video presentation, a designer of Linear Technology's LTC2379-18 demonstrates the outstanding performance of the device and shares his insights into the sophisticated design of this 18-bit ADC.

 

 

Precision matched resistors are used in a wide range of precision instrumentation applications including measurement and data acquisition, wireless RF, networking, automated test, medical, industrial controls and military equipment.  The LT®5400 is a family of quad, precision matched resistors designed for high performance signal conditioning applications such as difference amplifiers, precision dividers, precision gain stages, and bridge circuits. These thin-film resistors offer outstanding resistor-to-resistor matching and outstanding long term drift, in a small package.

 

 

LEDs are becoming both more popular and more powerful. Strings of 1A, 2A, 3A and higher current LEDs found in vehicles, billboards, industrial lighting, and many more applications need to be driven both accurately and efficiently from DC/DC converters. In many cases, a step-up and step-down topology is needed due to the voltage variation of both the LED string and the input source. In this case, a 4-switch synchronous buck-boost controller is the best solution for its efficiency and small circuit size

 

 

Synchronous Stepdown Regulator with Programmable Reference

 

 

Linear Technology's LT®3798 isolated controller with active power factor correction (PFC) is specifically designed for regulating bus voltages or driving constant current applications over a wide input range of 10V to 480V. The unique current sensing scheme delivers a well regulated voltage or current to the secondary side with no optocoupler. Output short circuit protection ensures long term reliability and a simple, compact solution footprint addresses a wide range of applications.

 

Portable electronic devices, powered by batteries, require battery chargers. In higher powered applications, efficiency and thermal management requirements lead to solutions using DC/DC converters. Linear Technology's LTC®4000 has the accuracy and features required to turn a DC/DC converter into a high performance battery charger with features such as charge current and input current regulation, charge voltage and system voltage regulation, C/X or timer termination, trickle charge, temperature qualified charging, instant on and ideal diode/ PowerPath control.

Watch how two engineers use Analog Devices' Circuits from the Lab to help solve their design challenge. From test data to hardware evaluation, to project integration, we make it easy to save time while lowering the risk in your circuit design.

 

 

In modern RF communication systems, signal integrity is of prime importance. To meet the system requirements, amplifiers, mixers and modulators must have a low noise figure and low distortion products. Additionally, as system designers work to squeeze increasingly more data into the available bandwidth, low phase noise signal sources assume an equal importance.

 

Battery life is paramount in modern battery-powered systems. Portable applications, such as remote sensors, require voltage regulators which have low current standby states and also able to provide bursts of high power. Linear Technology's LT®3970/LT3971 lead the industry in low current standby mode by consuming only 2.8uA of input current when regulating a 3.3V output with no load. The LT3970 and LT3971 have quiescent currents less than the self discharge rates of most batteries.

 

Measuring anything at any speed to 1ppm (.0001%) is hard. Dynamic measurement to this resolution is particularly challenging. Reliable 1ppm settling time measurement constitutes a high order difficulty problem requiring care in approach and experimental technique.

 

Stacks of lithium ion cells are used in new hybrid electric vehicles and uninterruptible power supplies. Maximizing the life and the safety of these high voltage, high power battery packs depends on sophisticated electronics.

Linear Technology's LTC6803 Multicell Battery Stack Monitor is the key component in a battery management system. The precision, noise immunity, low current modes, and built in diagnostics of the LTC6803 are critical to maintaining the proper state of charge and state of health of every cell. The unique stacking architecture reduces system cost by eliminating isolation components. Comprehensive applications support helps customers quickly integrate the LTC6803 into their products.

Stacks of lithium ion cells are used in new hybrid electric vehicles and uninterruptible power supplies. Maximizing the life and the safety of these high voltage, high power battery packs depends on sophisticated electronics.

Linear Technology's LTC6803 Multicell Battery Stack Monitor is the key component in a battery management system. The precision, noise immunity, low current modes, and built in diagnostics of the LTC6803 are critical to maintaining the proper state of charge and state of health of every cell. The unique stacking architecture reduces system cost by eliminating isolation components. Comprehensive applications support helps customers quickly integrate the LTC6803 into their products.

Compensating for unknown wire drops without remote sensing wires is now possible. The LT4180 continuously modulates the power supply output current to interrogate the line drop. Then the output is increased to match the drop providing up to a 50 to 1 improvement in regulation at the load.

 

Modern electronics systems require high performance point of load power supplies with advanced and intelligent power management. Linear Technology's LTC®3880 combines a best in class analog switching regulator controller with precise mixed signal data conversion for unsurpassed ease of power system design and management.

The analog current mode control architecture of LTC3880 ensures best loop stability, transient responses, accurate DC and dynamic current sharing. In addition to that, the LTC3880 is a comprehensive digital power manager with over 100 PMBus compliant commands and on-chip EEPROM. On-chip precision data converters and EEPROM allow for the capture and nonvolatile storage of regulator configuration settings and telemetry variables. LTC3880 is supported by LTpowerPlayTM Design Tool, an easy-to-use and powerful graphical user interface program. The LTC3880 can be used for computer, datacom, telecom equipment and storage systems.

odern FPGAs and servers operating at low voltages are sensitive to subtle supply drops. The droop may result from a combination of excess regulator noise, insufficient bandwidth in the supply regulator, excess ESR & ESL in the decoupling components, or distributed inductance in the power distribution.

To abate the risk of supply droop the typical approach is to surround the processor with an assortment of ceramic and bulk capacitors, thereby lending broadband support to the supplies with capacitors. This consumes board area and component budget.

Linear Technology's LT3070 is a POL regulator designed for FPGA & server applications. The LT3070 commands high bandwidth and fast transient performance by providing lower output impedance than bulk capacitors, thus eliminating the need for bulk capacitors. With the LT3070, the distributed decoupling network is reduced to just a few small ceramic capacitors. The high bandwidth combined with a 25uVRMS noise floor, make the LT3070 the fastest, quietest, lowest dropout, and most cost effective 5A monolithic linear regulator in the industry.

When Linear Technology provides a customer with a high speed ADC demo board we also provide PScope, the software to evaluate the demo board. PScope is a simple software package that can collect, and display data from high speed ADC demo boards. It will also provide a simple and easy way to measure the key performance parameters like signal to noise ratio, and spurious free dynamic range of high speed ADCs. PScope allows a customer to quickly pick up and evaluate a high speed ADC, leaving time to work on their design.

High-powered boost converters have historically suffered from the shortcoming that a DC path exists between the input and output nodes. Fault conditions, such as output shorts, could easily damage or destroy key components in this path. Other topologies, such as the SEPIC or inverting converters can also suffer from faults such as input over voltage or input reverse voltage conditions.

Linear Technology's LT3581 and LT3579 breaks new ground in high-powered monolithic DC/DC converter technology. Besides including high voltage high current power switches (3.3A, 42V for the LT3581 and 6A, 42V for the LT3579), the parts include built in fault protection features. With the addition of a few external components, power conversion circuits build around these parts can survive output shorts, input over voltages, input reverse voltages and over temperature conditions.

Most system designers use voltage references in their circuits. While many will agree that the performance may ultimately be limited by the reference, they are often unclear as to why. With so many reference products available, designers often choose based on a tradeoff between price and precision, using only initial accuracy and TC specs as a measure of precision.

As applications have evolved, so have voltage references. Features such as noise, thermal stability, load and line regulation and size may be just as important as, or more important than, the more obvious precision specifications.

Three new products from LTC, the LT6654, LTC®6655 and LT6656, have carefully chosen combinations of features and specifications to make them especially compatible with common types of applications.

This presentation gives details as to these features and introduces the products that are best suited for these types of system designs.

There is an increasing market for low power electronic devices located in remote locations, away from the power grid. Ideally, the power for these devices should be generated on-site using renewable energy. Perhaps the most visible form of renewable energy is from the sun. Converting this solar energy into electrical energy is easily done using Linear Technology's LTC3105 boost converter with Maximum Power Point Control. The MPPC feature allows the converter to extract the maximum power from a solar cell under varying sunlight conditions.

The LTC2978 features enable power supply supervision, monitoring, sequencing and trimming with unmatched accuracy. These features combined with our easy to use GUI, assist the power supply designer in defining and implementing complex power management schemes in a fraction of the time previously possible. Fault logging capability enables system level debug of power faults.

RF mixers are critical components that make up the modern transceivers used in 3G and 4G wireless infrastructure, communication gears and military systems. The receivers' robustness depends on their dynamic range performance.

The LTC5540/41/42/43 family of RF downconverting mixers covering frequencies from 600MHz to 4GHz, offers outstanding IIP3, conversion gain and noise figure performance. In addition, these mixers consume 40% less power than their closest rivals, while capable of handling unusually high in-band interference than any other comparable devices. Moreover, these mixers require fewer external components that reduce the solution footprint. Thus these best-in-class mixers allow us to build compact, power efficient receivers without compromising performance.

TimerBlox devices are novel solid state timing devices for voltage-controlled oscillation (VCO), low frequency clocking, pulse-width modulation (PWM), one-shot generation and signal delays. In this video, learn how these simple, small and accurate devices offer a new approach to common timing applications.

Most circuit designers are familiar with diode dynamic characteristics such as charge storage, voltage dependent capacitance and reverse recovery time. Less commonly acknowledged and manufacturer specified is diode forward turn-on time. This parameter describes the time required for a diode to turn on and clamp at its forward voltage drop.

Historically, this extremely short time, units of nanoseconds, has been so small that user and vendor alike have essentially ignored it. It is rarely discussed and almost never specified.

Recently, switching regulator clock rate and transition time have become faster, making diode turn-on time a critical issue. A potential difficulty due to diode turn-on time is that the resultant transitory “overshoot” voltage across the diode, even when restricted to nanoseconds, can induce overvoltage stress, causing switching regulator IC failure. This video provides a testing methology enabling proper diode selection for switching regulators.

Electromagnetic interference (EMI) falls into two broad categories - conducted and radiated. Conducted emissions refers to the noise that is carried on wires or other conductors, while radiated EMI floats through the air. While conducted EMI is certainly problematic, it is radiated EMI that makes design engineers cringe.
Linear Technology has developed a line of electromagnetically compatible (EMC) micromodule DC/DC converters. Like other members of the micromodule family, these parts are easy to design and use, but on top of that they have been independently certified to meet the stringent requirements of EN55022 Class B.

Boost power conversion is important function in many industrial, automotive and commercial applications. Higher power level customers have to deal with issues of high ripple currents, high power dissipation and higher EMI levels.

Linear Technology's LTC3788 breaks new ground in boost converter technology, achieving the highest efficiency with synchronous PolyPhase operation. Two separate synchronous boost channels allow the part to be used in single or dual output applications. The part can be used in PolyPhase applications with 2-, 4- and 6-phases. Also, the LTC3788 circuits can be smaller and less expensive, thanks to low power dissipation in synchronous rectifiers. Overall, LTC3788 can significantly improve the performance of high current, high power, boost circuits.

 

Precision digital-to-analog converters are key components in many instrumentation, industrial control and test equipment applications. When customers purchase an "N-bit" DAC, the expectation is that every parameter will be better than 1 least-significant bit. This is a difficult task, even at the 16-bit level.

Linear Technology's LTC2757 breaks new ground in DAC technology, achieving true 18-bit linearity and sub-part per million drift. Six SoftSpan output ranges greatly simplify the design of systems with multiple ranges. The LTC2757 can significantly improve the performance of precision systems while reducing cost by eliminating the need for temperature and linearity compensation.

There are many LED drivers on the market for low current LEDs and many others for high current LEDs. Low current LEDs are 20mA to 100mA LEDs. High current ones are 100mA to ~1A. But how many 20A LED drivers do you know? How about 40A? Not many. How about super fast µs rise time between 0A and 20A or between any two current levels? Not heard of. Not until now.

Linear Technology's LT3743 solves the problems of driving up to 40A LEDs with super fast 2µs PWM dimming between any current levels. It drives laser diodes too. The LT3743 does all this at 95% efficiency (12V input, 20A, 5V output) even in the low dimming range. The LT3743 can take up to 36V and can drive LEDs in series. The solution takes less than 2 square inches of PCB space.

The benefits of galvanic isolation extend beyond safety and protection from dangerous voltages to provide error-free communication in the presence of high edge rate transients, noise and high common mode voltage that would otherwise render a non-isolated network inoperative.

The new Isolator uModule Technology from Linear Technology provides a complete power and data isolation solution in one small 11.25mm x 15mm x 2.8mm surfacemount package. The LTM2881 incorporates a robust isolated RS485 transceiver and an isolated DC/DC converter capable of delivering up to 1W of power for the transceiver and auxiliary circuits. The module requires no external components – even the decoupling capacitors and an electrically switchable network termination resistor are built in. The ease of use and a small footprint make it more appealing than ever to design isolation into an RS485 network at every communication node.

Energy harvesting applications are finding their way into many remote monitoring applications where utility power is not available. New developments in ultralow power microcontrollers with their high level of integration are enabling monitoring systems which draw sub milliwatts of power. Various energy sources that were not useful as power sources for electronic sensors can now be used. The energy harvesting system must be highly efficient and present minimal loading effect on the energy source and the output storage elements when in their "sleep" mode.

The LTC3588-1 is a complete solution to energy harvesting systems. It requires only 3 external components plus an input and output energy storage element.

 

There is an alternative solution when deciding between a step-down switching regulator and a linear regulator. Switching regulators dissipate less heat than linear regulators especially when the input voltage is much higher than the output voltage or the output load current is relative high. On the other hand, linear regulators are very simple and don't require inductors. What if there was a switching regulator circuit could be simplified and fitted inside a surface mount package and the complete solution became as simple as a regulator's circuit? No inductors, no MOSFETs, no difficult calculations for compensation circuitry. On paper, it is a simple square box with a few resistors and capacitors. On a PCB, it is also a simple square box with a few resistors and capacitors.

Linear Technology's DC/DC µModule® regulators are complete switching regulator systems that are housed in compact surfacemount LGA (land grid array) package. All the complexity is addressed inside the package. What a designer needs to do is to simply choose a resistor to set the output voltage. This innovative regulator solution, allows system designers to save precious engineering time by minimizing the task of devising point-of-load regulators and obtain a complete solution that is encapsulated in a package resembling a surfacemount IC.

 

High-speed, high-resolution ADCs are critical components in communications and instrumentation applications. The interface between the final amplifier of the signal chain and the input pins of the ADC is challenging and time-consuming. Yet it is critical to the performance of the entire system. Traditionally, this requires impedance matching, developing an anti-alias filter and multiple iterations of the board layout to get everything right.

Linear Technology's LTM9001 greatly simplifies this part of the signal chain design. The ADC, the amplifier, all of the bypass capacitors and especially the matching and filter network are all integrated.

 

Current sources have been a well known but theoretical circuit component. Unlike voltage sources, a 0.01% accurate 2-terminal current source has been an elusive component that is not easily available and difficult to design. With the introduction of the LT3092, the current source as a drop-in component becomes a reality.

The LT3092 make an easily settable, high impedance and low temperature coefficient current source.

 

Frequently, voltage reference stability and noise define measurement limits in instrumentation systems. In particular, reference noise often sets stable resolution limits. Reference voltages have decreased with the continuing drop in system power supply voltages, making reference noise increasingly important. The compressed signal processing range mandates a commensurate reduction in reference noise to maintain resolution. Noise ultimately translates into quantization uncertainty in A-to-D converters, introducing jitter in applications such as scales, inertial navigation systems, infrared thermography, DVMs and medical imaging apparatus.

A new low voltage reference, the LTC6655, has only 0.3ppm (775nV) noise at 2.5VOUT. Verifying this extremely low noise level constitutes a high order difficulty measurement, requiring a 1Hz to 10Hz noise floor below 160 nanovolts. This video summarizes the measurement technique and presents results.

Technical papers     

• Radar Processing: FPGAs or GPUs?
• Build, Borrow, Buy – New Approaches to Addressing Software Complexity
• Full COM Express product range based on Intel Core processors
• K-Type Thermocouple Measurement System with Integrated Cold Junction Compensation

Infotainment Making HDTV in the car reliable and secure

December 15, 2011 | Texas instruments | 222901974

Unique Ser/Des technology supports encrypted video and audio content with full duplex bi-directional control channel over a single wire interface.