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The world's most precise clock has been fine-tuned to boost radar and GPS capabilities.The Cryogenic Sapphire Oscillator, or Sapphire Clock, has been enhanced by researchers from the University of Adelaide in South Australia to achieve near attosecond capability.The oscillator is 10-1000 times more stable than competing technology and allows users to take ultra-high precision measurements to improve the performance of electronic systems.Increased time precision is an integral part of radar technology and quantum computing, which have previously relied on the stability of quartz oscillators as well as atomic clocks such as the Hydrogen Maser.Atomic clocks are the gold-standard in time keeping for long-term stability over months and years. However, electronic systems need short-term stability over a second to control today's devices.The new Sapphire Clock has a short-term stability of better than 1x10-15, which is equivalent to only losing or gaining one second every 40 million years, 100 times better than commercial atomic clocks over a second.The original Sapphire Clock was developed by Professor Andre Luiten in 1989 in Western Australia before the team moved to South Australia to continue developing the device at the University of Adelaide.Lead researcher Martin O'Connor said the development group was in the process of modifying the device to meet the needs of various industries including defence, quantum computing and radio astronomy.The 100cm x 40cm x 40cm clock uses the natural resonance frequency of a synthetic sapphire crystal to maintain a steady oscillator signal.Associate Professor O'Connor said the machine could be reduced to 60 per cent of its size without losing much of its capability."Our technology is so far ahead of the game, it is now the time to transfer it into a commercial product," he said. "We can now tailor the oscillator to the application of our customers by reducing its size, weight and power consumption but it is still beyond current electronic systems."The Sapphire Clock, also known as a microwave oscillator, has a 5 cm cylinder-shaped crystal that is cooled to -269C.Microwave radiation is constantly propagating around the crystal with a natural resonance. The concept was first discovered by Lord Rayleigh in 1878 when he could hear someone whispering far away on the other side of the church dome at St Paul's Cathedral.The clock then uses small probes to pick up the faint resonance and amplifies it back to produce a pure frequency with near attosecond performance."An atomic clock uses an electronic transition between two energy levels of an atom as a frequency standard," Associate Professor O'Connor said."The atomic clock is what is commonly used in GPS satellites and in other quantum computing and astronomy applications but our clock is set to disrupt these current applications."The lab-based version already has an existing customer in the Defence Science and Technology Group (DST Group) in Adelaide, but Associate Professor O'Connor said the research group was also looking for more clients and was in discussion with a number of different industry groups.The research group is taking part in the Commonwealth Scientific and Industrial Research Organisation's (CSIRO's) On Prime pre-accelerator program, which helps teams identify customer segments and build business plans.Reference:KY163-ECS-2200B-500KY163-ECS-2100A-061KY163- ECS-2100A-640 

Integrated circuits (ICs) are the fundamental components of modern electronics. They are vital in manufacturing various systems and gadgets, including computers, smartphones, industrial machinery, and medical equipment. Indeed, integrated circuits are electronic components with small sizes and are composed of several parts and functions on a single semiconductor substrate, like silicon.Integrated circuits have various forms, each designed to meet particular needs and applications. Over time, these integrated circuits have developed into increasingly complex, powerful, and adaptable devices. Integrated circuits can be categorized according to several factors, such as their fabrication technology, functionality, and complexity. This article will explain the integrated circuit, its significant types, and the development trends of integrated circuits. What is an Integrated Circuit？An integrated circuit is just like a semiconductor wafer that has thousands or millions of small resistors, capacitors, transistors, and diodes. There are multiple examples of integrated circuits, which are computer memory, counter, oscillator, computer memory, logic gate, timer, processor, and microcontroller. An IC has become the fundamental building element for all modern electric devices. It is an integrated system that contains several miniaturized and interconnected components embedded in a thin silicon chip. An integrated circuit is developed by connecting a vast number of tiny MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) that are crammed onto a tiny chip. Compared to discrete circuits constructed with discrete electronic components, this results in circuits that are substantially faster, smaller, and less expensive.Since ICs can be produced in large quantities and use building blocks for integrated circuit design, the electronics industry has rushed to incorporate standardized ICs into designs that use discrete transistors. ICs are superior to discrete circuits in two crucial ways: cost and performance.Performance is much higher in ICs than in discrete counterparts because the components inside an IC have quicker switch times and use less power due to their proximity and compact size. ICs are highly inexpensive because they are generated by photolithography as a single unit instead of one transistor at a time. Less material is used when you compare packaged circuits to discrete circuits.Integrated circuits constantly evolve due to technological advancements, providing better functionality, lower power consumption, and higher performance. To fully utilize these potent components in their applications, engineers, designers, and enthusiasts must have a thorough understanding of the various types of integrated circuits.However, a significant drawback of integrated circuits is their high design cost and photolithography mask creation. Because of this, ICs can only be profitable when large manufacturing volumes are anticipated, enabling profit margins to justify them.Introduction to All Types of Integrated CircuitsThere are several types of integrated circuits (ICs), each designed especially for a specific use or application. ICs are categorized according to several factors, such as their fabrication technology, functionality, and complexity. Understanding the different types of integrated circuits is essential for engineers, designers, and enthusiasts, as it allows them to select the right ICs for their applications. This guide will discuss the multiple types of integrated circuits.Continuous electrical signals are intended to operate with analog integrated circuits. They are crucial in processing and manipulating analog data from the real world, including sensor signals, audio, and video. These chips can convert analog signals to digital, filtering and amplifying. Analog-to-digital converters (ADCs), voltage regulators, and operational amplifiers (op-amps) are examples of analog integrated circuits.Unlike analog ICs, digital ICs handle discrete digital signals and usually operate at two logic levels: 0 and 1. They are the fundamental digital electronics components of data processing, memory storage, and logical operations. Digital integrated circuits (ICs) include microcontrollers, microprocessors, and memory chips like RAM and flash memory.These circuits serve as a link between the analog and digital realms, combining analog and digital components. They play a role in applications that require processing and interfacing with both types of signals. You can commonly find mixed-signal ICs in telecommunications, audio processing, and sensor interfaces, as they enable converting real-world analog data into form and vice versa.RFICs are designed for high-frequency operations, making them ideal for communication devices such as cell phones, Wi-Fi routers, and satellite communication systems. These ICs excel at handling signals at radio frequencies to transmit and receive information effectively.Microprocessor CircuitsThe most complex integrated circuits are microprocessors. They contain billions of transistors that can be arranged to form countless distinct virtual circuits. Furthermore, every circuit possesses a distinct set of sound judgment qualities. These synchronized circuits, for good judgment, comprise the entirety of a microprocessor. The central processing unit (CPU) of a computer is frequently a microprocessor.             Similar to a marching band, the circuits use the bandmaster's guidance to execute their good judgment on the course best. The bandmaster is enclosed in a microchip and tries to communicate. It refers to the clock as well. The clock represents the ability to move quickly between states of sound judgment. Every time the clock changes states, each of the microprocessor's good judgment circuits does a certain task. Relying on the speed of the microprocessor allows calculations to be completed quickly.Data is stored in a few circuits called registers, which comprise a microprocessor. Every processor features a multitude of distinct register styles. Preprogrammed commands are kept in permanent registers. The output of operations on integers is saved in temporary registers.Digital Sign ProcessorsAn analog waveform that can be electrically recorded in any situation is a sign. An analog waveform quickly altered into a binary integer sequence is called a virtual sign. A virtual sign processor (DSP) processes indicators digitally as streams of 1s and 0s, as the name suggests. An analog-to-virtual converter also called an A-to-D or A/D converter, can convert a speech recording into virtual 1s and 0s.Following that, the virtual voice can be altered through complex mathematical calculations and a DSP. The circuit's DSP rules can be configured to digitally eliminate background noise from the waveform and identify the spaces between spoken words as history noise.Lastly, a D/A converter can transform the processed signal back into an analog signal for listening. Digital processing can filter history noise so fast that there is no discernible delay, and the sign appears to be heard in "real time."Memory CircuitsGenerally speaking, microprocessors should be able to store more statistics than some registers can hold. Massive memory circuits receive this excess of records. Dense arrays of parallel circuits that use voltage states to store records make up memory. The microprocessor's temporary library of programs or instructions is also kept in memory.To provide functionality without requiring additional space, manufacturers always try to reduce the size of memory circuits. Moreover, smaller additives are usually less expensive to produce, operate more effectively, and require less electricity.Application-specific Integrated CircuitsAn analog or digital application-specific integrated circuit (ASIC) performs only one task and cannot be reconfigured. For instance, an RC car's speed controller integrated circuit is hardwired to perform a single function and is never intended to evolve into a microprocessor. An application-specific integrated circuit is not capable of responding to alternative commands.Efficiency plays a role in electronic devices. Power management integrated circuits (ICs) are responsible for controlling and distributing power in systems, ensuring power usage and stable voltage supply. These ICs are commonly found in battery-powered devices like smartphones and laptops, power supplies, and voltage regulation circuits.A virtual circuit accepts the best voltages of specific values. A binary circuit employs optimal states. In this circuit configuration, the binary numbers "on" and "off" represent 1 and 0, respectively. It also makes use of the good judgment of Boolean algebra. (Boolean algebra is also used to perform binary quantity device arithmetic.) These fundamental elements work with the IC layout to enable virtual computer systems and gadgets to perform the desired operations.Development Trends of Integrated CircuitsLet's discuss the emerging trends of Integrated circuits in detail.High IntegrationWith the trend of thin and short electronic devices, consumers now expect products to be lighter, smaller, and packed with features. Manufacturers of consumer electronics have raised the bar for portable mobile devices' power management systems to serve consumers' needs better. Combining several features into a single power management chip can reduce the number of external devices, enhance the system's long-term reliability, decrease solution size, and boost profit margin.High Efficiency and Low Power ConsumptionAs the consumer electronics industry continues to grow, customers are now demanding the best products that have performance and longer battery life. That is why manufacturers maintain low power consumption by improving continuous device performance. Indeed, low-power and high-performance power management chip products are anticipated to be preferred by the market. Low-power power supply design is also becoming a critical technology impacting electronic system design.AI and Machine Learning HardwareSpecialized integrated circuits (ICs) are generated specifically for machine learning and artificial intelligence (AI). Hardware specifically made to speed up AI workloads includes tensor processing units (TPUs) and graphics processing units (GPUs). The development of image recognition, natural language processing, autonomous vehicles, and many other AI-driven technologies depends on these AI-focused integrated circuits. There will likely be an increase in demand for specialized hardware as AI spreads in various industries.More and more integrated circuits (ICs) are programmable and customizable, allowing hardware designers to customize components for particular uses. For example, field-programmable gate arrays (FPGAs) have various applications since they enable logic gate reconfiguration after manufacturing. Another example of a customized integrated circuit (IC) that balances performance and power efficiency is the application-specific integrated circuit (ASIC). These programmability and customization trends allow engineers to tailor their designs to meet specific requirements.Development trends in integrated circuits align with sustainability objectives as people's awareness of how electronics affect the environment grows. This entails using fewer dangerous materials, increasing energy economy, and designing integrated circuits (ICs) for recycling and appropriate disposal. In short, optimizing the end-of-life disposal process for electronic components is becoming a priority, and green IC design practices, like using lead-free and RoHS-compliant materials, have become common.Packaging technologies have advanced to meet the demands for smaller form factors, better thermal management, and enhanced signal integrity as integrated circuits (ICs) become more complex and functional. Indeed, chiplet-based architectures, wafer-level packaging, and three-dimensional stacking are advanced packaging options that give IC designers new ways to tackle the increasing complexity of contemporary electronic systems. Therefore, by minimizing the distances between chip components, these packaging techniques improve performance and reduce energy consumption.The need for reliable and secure ICs is more significant than ever as technology increasingly integrates into our daily lives. Hardware security features such as tamper resistance, secure boot processes, and hardware-based encryption are all included in this trend. Furthermore, supply chain security—ensuring that integrated circuits (ICs) are not compromised during their manufacturing and distribution processes—is becoming increasingly important. This is especially crucial in defense applications and critical infrastructure.ConclusionIn summary, integrated circuits (ICs) are the building blocks of modern electronics, driving innovation and establishing a world of ever-expanding digital technology. We've talked about different types of integrated circuits that can be extremely important in the digital world. These integrated circuits have developed over time, becoming more effective and energy-efficient while also adjusting to the particular requirements of various technologies.Furthermore, integrated circuit development trends are constantly changing to satisfy the ever-increasing demands of the digital era. ICs continue to be at the forefront of technological advancement, whether it is through their pursuit of energy efficiency, security, or specialized hardware for emerging technologies. To effectively navigate the complex landscape of integrated circuit design and production, industry leaders need to stay up to date on these trends.

Warm hints: The word in this article is about 1000 and the  reading time is about 6 minutes. MIT researchers found a way to triple the efficiency by using "topological" materials with special electronic properties. Although previous research has indicated that topological materials could be used to create efficient thermoelectric systems, little is known about how electrons in such topological materials can move in response to temperature differences to produce a thermoelectric effect. Researchers not only found that they can push the boundaries of this nanostructured material in a way that makes topological materials a good thermoelectric material,more so than conventional semiconductors like silicon,but also this could be a clean-energy way to help us use a heat source to generate electricity, which will lessen our release of carbon dioxide. NewsToday, thermoelectric devices are used for relatively low-power applications, such as powering small sensors along oil pipelines, backing up batteries on space probes, and cooling minifridges. Scientists hope to develop more efficient thermoelectric devices that will harvest heat produced as a byproduct of industrial processes and combustion engines and convert it into electricity. However, thermoelectric devices' power, or the amount of energy they can generate, is currently limited. "We discovered that we can push the limits of this nanostructured material in a way that makes topological materials a better thermoelectric material than traditional semiconductors like silicon," says Te-Huan Liu, a postdoctoral researcher in MIT's Department of Mechanical Engineering. "In the end, this could be a clean-energy way to help us use a heat source to generate electricity, which will lessen our release of carbon dioxide," Liu added. Liu is first author of the PNAS paper, which includes graduate students Jiawei Zhou, Zhiwei Ding, and Qichen Song; Mingda Li, assistant professor in the Department of Nuclear Science and Engineering; former graduate student Bolin Liao, now an assistant professor at the University of California at Santa Barbara; Liang Fu, the Biedenharn Associate Professor of Physics; and Gang Chen, the Soderberg Professor and head of the Department of Mechanical Engineering.A Path Travel Freely When a thermoelectric material is exposed to a temperature gradient — for example, one end is heated while the other is cooled — electrons begin to flow from the hot end to the cold end, resulting in an electric current. The greater the temperature difference, the more electric current and power are made. The amount of energy that can be produced is determined by the electron transport properties of a given material. Scientists have discovered that certain topological materials can be converted into efficient thermoelectric devices using nanostructuring, a technique used by scientists to create a material by patterning its features at the nanometer scale. Scientists believe that the thermoelectric benefit of topological materials stems from decreased thermal conductivity in their nanostructures. However, it is uncertain how this increase in efficiency relates to the material's inherent, topological properties.     Liu and his colleagues investigated the thermoelectric efficiency of tin telluride, a topological material considered to be a strong thermoelectric material, to try to address this issue. Tin telluride electrons also have unusual properties that resemble a class of topological materials known as Dirac materials. The researchers wanted to understand the effect of nanostructuring on the thermoelectric efficiency of tin telluride by simulating electron movement through the material. Scientists often use a calculation known as the "mean free path" to characterize electron transport. This is the average distance an electron with a given energy can freely travel within a material before being dispersed by different objects or defects in that material. Nanostructured materials resemble a patchwork of tiny crystals, each with its own boundary, known as grain boundaries, that separates one crystal from the next. As electrons come into contact with these limits, they scatter in a variety of ways. Electrons with long mean free paths scatter violently, similar to bullets ricocheting off a wall, whereas electrons with shorter mean free paths are much less affected. The researchers discovered that the electron properties of tin telluride have an important effect on their mean free paths in their simulations. They plotted the spectrum of electron energies in tin telluride against the related mean free paths and discovered that the resulting graph looked very different from that of most traditional semiconductors. In particular, for tin telluride and probably other topological materials, the findings indicate that higher-energy electrons have a shorter mean free path, while lower-energy electrons have a longer mean free path. The researchers then investigated how these electron properties influence the thermoelectric efficiency of tin telluride by essentially summing up the thermoelectric contributions from electrons with different energies and mean free paths. It turns out that the ability of a substance to conduct electricity, or produce a flow of electrons, under a temperature gradient is largely determined by the electron energy. They discovered that lower-energy electrons have a negative effect on the production of a voltage difference, and hence electric current. Since low-energy electrons have longer mean free paths, they can be dispersed more intensely by grain boundaries than high-energy electrons.Size DownGoing a step further in their simulations, the team experimented with the size of individual grains of tin telluride to see whether this had some impact on the movement of electrons under a temperature gradient. They discovered that raising the diameter of an average grain to around 10 nanometers, putting its boundaries closer together, increased the contribution of higher-energy electrons. Higher-energy electrons contribute much more to the material's electrical conduction with smaller grain sizes than lower-energy electrons because they have shorter mean free paths and are less likely to scatter against grain boundaries. As a result, a greater voltage difference can be produced. Furthermore, the researchers discovered that shrinking the average grain size of tin telluride to around 10 nanometers yielded three times the amount of electricity that the material would have produced with larger grains. Although the findings are based on simulations, Liu claims that researchers can achieve comparable results by synthesizing tin telluride and other topological materials and changing their grain size using a nanostructuring technique. Other researchers have proposed that shrinking the grain size of a material can improve its thermoelectric efficiency, but Liu claims that they have mostly assumed that the ideal size is much larger than 10 nanometers. "In our simulations, we discovered that we can shrink the grain size of a topological material far more than previously thought, and based on this principle, we can increase its performance," Liu says. Tin telluride is one of the topological materials that have yet to be discovered. If researchers can determine the optimal grain size for each of these materials, topological materials, according to Liu, can soon be a viable, more effective alternative to producing renewable energy. ConclusionLiu believes that topological materials are excellent for thermoelectric materials, and our findings indicate that this is a very promising material for potential applications. The Solid-State Solar Thermal Energy Conversion Center, an Energy Frontier Research Center of the United States Department of Energy, and the Defense Advanced Research Projects Agency contributed to this research (DARPA). Article From Proceedings of the National Academy of SciencesArticle Edited by kynix 

TechInsights discusses which wafer bonding technology hints at a possible future for stacked dies.Samsung’s S7 smartphones are offered with several unique builds depending on the country of use. For example, the US models sport the Qualcomm Snapdragon 820 processor and the European versions that we at TechInsights bought contained the Samsung Exynos 8 Octa processor. Both of these processors were fabbed by Samsung using its 14 nm Low Power Plus (LPP) process. Other chips in the phones were dual sourced as well, including their 12 megapixel CMOS image sensors. We knew that Sony was one vendor and Samsung the other, but how was the split done and what technologies were used?Figure 1 shows the US (SM-G930A) and European (SM-G930F) smartphones with their cover plates removed to expose their circuit boards and camera modules. The layout of the two circuit boards is quite similar but we note small differences in the metal housings used by the two image sensors. We originally thought this to be a marker for the Sony and Samsung variants, but this turned out not to be the case.Figure 1 Samsung S7 with cover removed SM-G930A US model left, SM-G930F European model right (Source: TechInsights)Figure 2 shows the camera modules from the US sourced Smartphone (left) and the European model (right). The US model has ‘SONY’ printed on its flex ribbon and our examination of the die confirms it to be the Sony IMX260 12 megapixel backside illuminated CMOS image sensor. Our first sample of the European phone’s module revealed it to be the Samsung S5L2L1 backside CMOS image sensor, but our remaining six European S7 phones housed the Sony image sensors. This was a surprise as we had assumed that Samsung would do a geographic split for the image sensors, much like they did for the Qualcomm Snapdragon and Exynos processors.Figure 2: CMOS Image Sensor Modules (Source: TechInsights) SM-G930A US model left, SM-G930F European model rightFigures 3 and 4 are die photographs of the Sony IMX260 and Samsung S5k2L1SX 12 Mp backside illuminated (BSI) CMOS image sensors (CIS), respectively that were removed from the two phones. We have removed the organic microlenses and color filters that cover the two dies so that we can get a better view of the pixel array size, and in the case of the Samsung die, the layout of through silicon vias (TSVs) that are used to connect the CIS die to an underlying control ASIC.The two dies are the same size and their array sizes are essentially the same size as well. No surprise here as the two dies use what appear to be the same optical housings in the European versions of the phones.Sony had used TSVs in their earlier CMOS image sensors and we had expected the same for the IMX260. But we don’t see them, as they have been replaced by a direct wafer bonding process that we will discuss later.The Samsung CMOS image sensor has arrays of TSVs along its perimeter and these are used to make the electrical connections to the underlying ASIC.Figure 3: Sony IMX260 CMOS Image Sensor (Source: TechInsights)Figure 4: Samsung S5k2L1SX CMOS Image Sensor (Source: TechInsights)

Access to clean, safe water is one of the world’s pressing needs, yet today’s water distribution systems lose an average of 20 percent of their supply because of leaks. These leaks not only make shortages worse but also can cause serious structural damage to buildings and roads by undermining foundations, which is a great loss.Many property losses experienced by business owners involve water damage caused by leaky pipes. Water can be very destructive whether it seeps from a loose fitting or gushes from a ruptured main.Unfortunately, leak detection systems are expensive and slow to operate — and they don’t work well in systems that use wood, clay, or plastic pipes, which account for the majority of systems in the developing world. Now, a new system developed by researchers at MIT could provide a fast, inexpensive solution that can find even tiny leaks with pinpoint precision, no matter what the pipes are made of. The system, which has been under development and testing for nine years by professor of mechanical engineering Kamal Youcef-Toumi, graduate student You Wu, and two others, will be described in detail at the upcoming IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) in September. Meanwhile, the team is carrying out tests this summer on 12-inch concrete water-distribution pipes under the city of Monterrey, Mexico. The system uses a small, rubbery robotic device that looks something like an oversized badminton birdie. The device can be inserted into the water system through any fire hydrant. It then moves passively with the flow, logging its position as it goes. It detects even small variations in pressure by sensing the pull at the edges of its soft rubber skirt, which fills the diameter of of the pipe.(The fast, inexpensive robotic device that developed by engineers from MIT can find even tiny leaks in pipes with pinpoint precision, no matter what the pipes are made of.)This device contains two parts: "skirt" sensor and soft body drone. It is then retrieved using a net through another hydrant, and its data is uploaded. No digging is required, and there is no need for any interruption of the water service. In addition to the passive device that is pushed by the water flow, the team also produced an active version that can control its motion.Monterrey itself has a strong incentive to take part in this study, since it loses an estimated 40 percent of its water supply to leaks every year, costing the city about $80 million in lost revenue. Leaks can also lead to contamination of the water supply when polluted water backs up into the distribution pipes. The MIT team, called PipeGuard, intends to commercialize its robotic detection system to help alleviate such losses. In Saudi Arabia, where most drinking water is provided through expensive desalination plants, some 33 percent is lost through leakage. That’s why that desert nation’s King Fahd University of Petroleum and Minerals has sponsored and collaborated on much of the MIT team’s work, including successful field tests there earlier this year that resulted in some further design improvements to the system, Youcef-Toumi says. DKNY CEO Caroline Brown, said “PipeGuard has created a simple, pragmatic and elegant solution to a complex problem. … This robot is a great example of utilizing smart design to simplify complexity and maximize efficiency.”

The LTC2185 is a 125Msps 16-bit ADC with excellent noise and linearity performance while only consuming 185mW per channel. It is ideal for demanding low power applications that require excellent AC performance. A high performance ADC like the LTC2185 requires a high performance amplifier driving it to maintain the excellent performance. The ADA4927-1 delivers the linearity performance required by the LTC2185 while only consuming 215mW. The well designed package of the ADA4927-1 allows for a simple layout that reduces parasitic capacitance in the feedback path that can erode the phase margin of the amplifier. This combination of ADC and driver allows excellent performance from 62.5-125MHz a region where other high speed amplifiers are lacking.  The LTC2185 is a two-channel simultaneous sampling parallel ADC which offers a choice of full-rate CMOS, or double data rate (DDR) CMOS/LVDS digital outputs. Pin-compatible speed grade options include 25Msps, 40Msps, 65Msps, 80Msps and 105Msps with approximate power dissipation of just 1.5mW/Msps per channel. It includes popular features such as the digital output randomizer and alternate bit polarity (ABP) mode that minimize digital feedback when using parallel CMOS outputs.  Analog full power bandwidth of 550MHz and ultralow jitter of 0.07psRMS allows under-sampling of IF frequencies with excellent noise performance. To maintain this level of performance the LTC2185 needs to be driven with an appropriate amplifier like the ADA4927-1. The ADA4927 is a high speed differential current feedback amplifier. Fabricated on Analog Devices’ silicon-germanium process, the ADA4927-1 has excellent distortion and an input voltage noise of only 1.3nV/rtHz. This allows it to drive high speed ADCs like the LTC2185. The gain of the ADA4927-1 is set with external feedback resistors located next to the input pins.  By keeping the feedback pins and input pins close on the package, the ADA4927-1 provides a clean layout and minimizing the parasitic capacitance in the feedback network. This make the ADA4927-1 an ideal choice for driving high performance ADCs, like the LTC2185, from DC to 125 MHz. Figure 1 shows a schematic of the ADA4927-1 driving the LTC2185. The corresponding layout is shown in figure 2.  The feedback pins on the ADA4927-1 are adjacent to the input pins which minimizes the parasitic capacitance of the feedback node and improves the phase margin of the amplifier. It also Simplifier the layout by making it possible to place feedback resistors directly across the two pins and not having additional trace length in the feedback path. There is a simple filter between the amplifier and ADC that reduces the wideband noise of the amplifier and improves the SNR of the system. This filter also attenuates the sampling glitches from the ADC before they reach the amplifier. This helps keep the output network of the ADA4927 from oscillating in response to these glitches. This filter network can be modified to accommodate a wide range of input bandwidth requirements. (Figure 1:  Schematic showing an ADA4927-1 driving one channel of the LTC2185)(Figure 2:  Layout showing an ADA4927-1 driving once channel of the LTC2185)Figure 3 and figure 4 show the SNR and SFDR of the LTC2185 and ADA4927-1 combination. The SFDR stays above 67dB out to 125MHz while the SNR is better than 63dB to the same frequency. This combination only consumes 250mW. With a sample rate of 125Msps, this combination provides good performance through the entire 2nd Nyquist zone where other amplifiers begin to have poor linearity.  (Figure 3:  SNR of the LTC2185 driven with the ADA4927-1)(Figure 4:  SFDR of the LTC2185 driven with the ADA4927-1) Using the ADA4927-1 to drive the LTC2185 provides excellent linearity while keeping the power consumption low. The fact that the ADA4927-1 stays very linear out to 125MHz allows this ADC amplifier combination to be used in demanding communication and medical applications that require the use of the second Nyquist zone of the LTC2185. The pin out of the ADA4927-1 and filter design minimize the complexity of the layout while maintaining excellent performance on a low power budget. Ref.KY32-LTC2185KY362-ADA4927-1