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Two wideband current sensors from Allegro, the ACS37030 and ACS37032, ensure efficiency and reliability in GaN and SiC FET power architectures. With an operating bandwidth of DC to 5 MHz, the devices are suitable for electrified vehicles, clean energy solutions, and data center applications.

The ACS37030 and ACS37032 offer current sensing ranges of ±20 A, ±40 A, and ±65 A, with a typical response time of 40 ns. Both devices employ dual signal paths. One path captures low-frequency and DC current using Hall-effect elements. The other path captures high-frequency current data through an inductive coil. These two paths are summed to enable sensing from DC to 5 MHz in a single device.

The current sensors achieve stable and safe control, while reducing EMI. Sensitivity error over temperature is ±2%. The properties of the inductive coil increase signal to noise ratio (SNR) as frequency increases, minimizing noise at the output. The ACS37030 provides a zero current reference output, while the ACS37032 offers an overcurrent fault output.

Housed in compact 6-pin SOIC packages, the sensors have a rated isolation voltage of 3500 VRMS and a basic working voltage of 840 VRMS. They operate over a temperature range of -40° to +150°C. To learn more about the ACS37030 and ACS37032 current sensors, click here.

Allegro MicroSystems

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MaxLinear is offering a product design kit (PDK) to help cable manufacturers integrate the Keystone PAM4 DSP into their active electrical cables. According to MaxLinear, the 5-nm PAM4 DSP can yield up to a 40% power savings over competitor solutions when used in active electrical cable (AEC) applications.

Unlike passive cables, active electrical cables actively boost signals, allowing for longer distances (up to 7 meters for 400G); higher bandwidth; and thinner, lighter cables. Keystone PAM4 DSPs based on 5-nm CMOS technology enable designers to build high-speed cables that maximize reach and minimize power consumption in next-generation hyperscale cloud networks. To ease DSP integration, the PDK includes strong application support, multiple tools to optimize and monitor performance, and both hardware and software reference designs.

Keystone 5-nm DSPs cater to 400G and 800G applications and provide a 106.25-Gbps host-side electrical I/O that aligns with the line-side interface rate. Variants support single-mode optics (EML and SiPh) and multimode optics (VCSEL transceivers and AOCs), as well as AECs. The family also includes companion transimpedance amplifiers.

For more information about the Keystone 5-nm PAM4 DSPs (MxL93642, MxL93643, MxL93682, and MxL93683), click here.

MaxLinear

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Sara-R520M19, an LTE-M and NB-IoT module from Swiss provider u-blox, delivers accurate positioning data concurrent with LTE communication. Simultaneous GNSS and cellular connectivity is an important factor for applications requiring continuous or cyclic tracking, such as utility metering and asset tracking.

The Sara-R520M10 module incorporates the company’s UBX-R52 cellular chip, M10 GNSS receiver, and dedicated GNSS antenna interface in a 16×26×2.2-mm, 96-pin LGA package. A variant without the GNSS receiver, the Sara-R520, is also available for general-purpose applications. This model features SpotNow, an assisted GPS receiver for applications requiring occasional tracking. 

The Sara-R52 series offers 23 dBm of RF output power to ensure stable connectivity. Modules include an Open CPU (uCPU) feature that allows users to run their own software on the chip without the need for an external MCU. An onboard smart connection manager performs automatic connectivity management. Its function is to achieve either the best performance or the lowest power consumption. This is useful when a connection is lost and needs to be re-established.

In addition to the Sara-R52 series, u-blox released the Lexi-R520 LTE-M module. The Lexi-R520 furnishes the same features as the Sara-R520, but in a smaller form factor. Its 16×16×2-mm, 133-pin LGA package lends itself to applications like wearables.

Samples of the LTE-M modules are available now, with volume production scheduled for Q3 2024.

Sara-R52 series product page

Lexi-R520 product page

u-blox

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Asahi Kasei’s AK5707 ADC packs an acoustic activity analyzer (AAA) that can be configured to detect specific types of acoustic events, such as breaking glass. This integrated analog acoustic event detector makes the AK5707 16-bit monaural ADC well-suited for IoT security applications, like wireless cameras and smart doorbells.

Consuming just 34 µA, the AK5707’s AAA block listens for acoustic events that fit user-customizable profiles. Upon detection, the AAA activates the ADC and initiates recording to an integrated audio buffer. Simultaneously, it generates an interrupt to wake the external SoC.

Unlike typical loudness-based detection, the AAA constantly tracks the current noise floor and adjusts its detection parameters in response. AAA detection not only reduces false positives, but also increases battery life in noisier environments. Asahi Kasei offers a suite of detection profiles for the AAA, including glass-break, alarm patterns, crying baby, and human voice. These profiles are configurable, with multiple acoustic parameters set by the user.

The 16-bit, 48-kHz ADC block of the AK5707, which can be powered on and off independently of the AAA, achieves a signal-to-noise ratio of 95 dB, while consuming only 200 µA. Built-in AC coupling capacitors allow for a 3.2 mm2 PCB area, including one external capacitor.

The AK5707 comes in a tiny 1.53×1.58-mm WLCSP. It is currently sampling, with mass production scheduled to begin in September 2024.

AK5707 product page

Asahi Kasei Microdevices 

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Cirrus Logic, Intel, and Microsoft are developing a reference design that teams Intel’s forthcoming Lunar Lake processor with Cirrus audio and power devices. The reference platform will help developers create more immersive audio for laptop PCs, while reducing heat generation and extending battery life to enable smaller, thinner designs.

Claiming to bring best-in-class audio to more PCs, the reference design employs the Cirrus Logic CS42L43 SmartHIFI codec, CS35L56 audio amplifier, and CP9314 switched-capacitor power converter. The codec and audio amplifiers deliver louder bass, clearer voice, and lower distortion to both the speaker and the headset. The power converter promises to reduce power and heat, as well as fan noise.

In addition, the audio design will assist with the transition to the MIPI SoundWire interface and Microsoft’s ACX (audio class extension) framework. Along with built-in security features, the design supports next-generation features like spatial audio. It is scalable across different processors, speakers, and notebook designs, allowing OEMs to implement audio subsystems that scale in channel count and features.

Intel’s Lunar Lake processor for portable PCs is expected to launch later this year.

Cirrus Logic 

Intel

Microsoft

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Conformance approval is a major step in bringing devices for the Internet of things (IoT) to the market. To ensure that these devices work properly, they need to be certified by testing laboratories accredited by certification bodies such as GCF, PTCRB or CTIA. With the successful verification of the 3GPP Rel. 17 NTN NB-IoT test cases in work item 333 at the CAG #77 meeting, using the R&S CMW500, the Global Certification Forum was able to activate the work item, kicking off conformance testing for NTN NB-IoT devices.

With this accomplishment, Rohde & Schwarz together with tier 1 chipset vendors like Qualcomm Technologies, Mediatek, and Sony Semiconductor Israel’s Altair and their respective platforms have contributed significantly to the adoption of non-terrestrial network-based IoT use cases spanning multiple sectors such as smartphone, consumer, automotive, agriculture, maritime, logistics, and mining. The NTN NB-IoT protocol test cases of work item 333 cover NTN-specific signaling aspects for NB-IoT devices as specified in 3GPP Rel.17 TS 36.523-1.

Rohde & Schwarz has equipped its market-leading NB-IoT solution with 3GPP Rel. 17 NTN features to provide the ecosystem with R&D, production, and conformance testing functions. The protocol conformance test cases were developed using the R&S CMW500 radio communication tester, which allows engineers to assess their NTN NB-IoT devices under realistic conditions, establishing a real-time, comprehensive connection with the simulated satellite network and testing the relevant signaling and RF scenarios in line with the 3GPP Rel. 17 specification. The test solution emulates geosynchronous orbit (GSO) and geostationary orbit (GEO) as well as low earth orbit (LEO) constellations. It helps engineers to verify NTN device challenges like time and frequency synchronization due to prolonged delay and Doppler effect, low Signal-to-Interference-plus-Noise Ratio (SINR), power saving mechanisms, satellite ephemerides, and GNSS acquisition, to name just a few of the core features.

The official GCF platform R&S CMW-IoT is a single box solution for conformance testing including PCT, RRM and RF. In addition to this, the single box also supports carrier acceptance testing.

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With latest ground-breaking innovation, Technovos is proactively paving the way for a new era of Green Mobility Solutions, amalgamating automotive capacity to eliminate manual labour-intensive tasks.

Technovos- a leading developer of sustainable mobility solutions disrupting the Cleantech and Agritech landscape has recently launched its latest yet innovative offering the GaadE Electric Wheelbarrow to redefine manual-material handling tasks. The launch signifies a revolutionary stride in labour-intensive tasks, reshaping the peripheral of diverse industries.

Challenging conventions and breaking the boundaries of possibilities in the realm of agriculture, logistics, construction and many more, the Wheelbarrow stands at the edge of sustainability convergence. Moving beyond the limits of being an electric motor-driven upgrade of its traditional counterparts, it embodies an inaugural fusion of cutting-edge technology and eco-friendliness.

Thrilled with the launch of its latest offering, Bharath Anantha Srinivas, CEO and Founder of Technovos, commented, “In a world where technological innovation continues to dominate every facet of our daily lives, Technovos aims to become the catalyst for revolutionising the Agritech and Sustainable mobility space. With our latest product, the dynamic Electric Wheelbarrow, we’ve crafted a breakthrough in the realm of material movement, being the premier platform to offer a purpose-driven electric wheelbarrow, designed to exude excellence from concept development to integration and assembly.”

With Electric Propulsion at its forefront, it employs a 4KW 3Phase Induction motor which helps in efficiently transporting substantial loads. Utilising advanced sensors and AI algorithms, it has opened the doors to self-navigation, along with obstacle avoidance and precise manoeuvring. Furthermore, it boasts a loading capacity to move 80% of the applications to minimise the need for human effort.

Accelerating green mobility to an elevated level, it operates with zero-emissions and energy-efficient mechanisms, emerging as the gateway to fostering a sustainable environment.

Offering an opportunity to partake in a future driven by automation, the introduction of electric wheelbarrows in the Precision AgriTech segment is a game-changing innovation. Being a labour-intensive sector, it will deliver farmers and agronomists an escape from manual lifting, opening doors to a versatile and efficient solution that is designed to improve farm operations, whilst enhancing crop management.

With multifaceted warehouse operations, the seamless integration of the GaadE- Electric Wheel-Barrow marks a significant leap forward in material handling and sustainability endeavours. This ingenious solution is poised to transform the warehousing and logistic industries, with access to streamlined operations and reduced costs, whilst enhancing the notions of industrial safety and environmental responsibility.

In the absence of a purpose-built machine for the hyper-local segment, Technovos has carved a distinctive niche with the augment of India’s premier purpose-driven Electric Wheelbarrow. With the launch of this innovative solution, the company has showcased its commitment to becoming the vanguard developer of sustainable mobility solutions that address the gap of implausible material movement methods in an array of markets. Autonomous wheelbarrow after this Electric wheelbarrow is the next innovation planned by Technovos.

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Infineon Technologies has announced a collaboration with Worksport Ltd. Worksport will use Infineon’s GaN power semiconductors GS-065-060-5-B-A in the converters for its portable power stations to increase efficiency and power density. Enabled by Infineon’s GaN transistors, the power converters will be lighter and smaller in size with reduced system costs. In addition, Infineon will support Worksport in the optimization of circuits and layout design to further reduce size and increase power density.

“Infineon’s high-quality standard and solid supply chain provide us with the best components to ensure power-dense converters for our COR system product line and contribute to a first-class end product performance,” said Worksport CEO Steven Rossi. The company’s COR battery system can be integrated into a pickup truck or recharged by any solar panel or wall outlet. By replacing the former silicon switch in the power converter with Infineon’s GaN power semiconductors and operating the transistors at higher switching frequency, Worksport will be able to reduce the battery system weight by 33 percent and system costs by up to 25 percent.

The working relationship with Infineon will also help Worksport to reduce CO2 in the manufacturing process. GaN is proving itself as a game-changing technology across many markets and applications. For example, in data centers, GaN solutions have a global energy savings potential of 21 TWh annually, 10 million tons of Carbon Dioxide (CO2) equivalent. “In order to further drive electrification and decarbonization, the industry’s power designs require innovation,” said Johannes Schoiswohl, Business Line Head GaN Systems of Infineon’s Power & Sensor Systems Division. “With our GaN power semiconductors we enable Worksport to create the next generation portable power stations that users require.”

Infineon’s GS-065-060-5-B-A is an Automotive-grade 650 V enhancement mode GaN-on-Silicon power transistor. It offers very low junction-to-case thermal resistance for demanding high-power applications such as on-board chargers, industrial motor drives and solar inverters. Furthermore, it features simple gate drive requirements (0 V to 6 V) and a transient tolerant gate drive (-20 / +10 V).

Availability

The GS-065-060-5-B-A is available in a bottom-cooled, low-inductance GaNPX® package.

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Soctera of Ithaca, NY USA (a developer of thermally optimized III-nitride millimeter-wave power amplifiers) has demonstrated high-electron-mobility transistors (HEMTs) exhibiting a peak surface temperature rise of just 59°C while dissipating 10.4W/mm. Typical gallium nitride (GaN) HEMTs reach the standard operating temperature limit of 225°C when dissipating about 5W/mm...

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ESK-SIC GmbH of Frechen near Cologne, Germany (which manufactures high-performance materials for industrial applications) and Kyocera (which manufactures technical ceramics and semiconductor technologies) have entered into a strategic partnership to develop solutions for the sustainable production of silicon carbide (SiC) and associated end-products...

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The metaverse and extended reality (XR) applications are considered critical to unlocking the full consumer potential of the 5G technology. Rigorous testing is crucial to ensure the performance and market acceptance of these immersive experiences. Rohde & Schwarz and Slalom have collaborated to address this need, developing essential tools to test XR use cases thoroughly prior to market launch. At Mobile World Congress 2024, visitors can experience a first demonstration of how to enable tomorrow’s augmented reality.

The 3rd Generation Partnership Project (3GPP) closely examined extended reality (XR) applications with Release 17. This was pivotal in identifying the current limitations and potential enhancements in today’s 5G specifications, paving the way for 5G-Advanced, which will be addressed in Release 18. One of the key areas for 5G-Advanced is the development of animated avatar calls that use augmented reality. This is considered a stepping stone toward a broader integration of the metaverse.

Rohde & Schwarz, a leader in test and measurement solutions, has partnered with Slalom, a next-generation professional services company creating value at the intersection of business, technology, and humanity, to create a state-of-the-art lab environment. This collaboration has resulted in a test bed for XR-based use cases. At the test bed’s core is the R&S CMX500 5G one-box signaling tester from Rohde & Schwarz. This innovative setup empowers network operators to evaluate XR-based applications and services in a controlled environment, ensuring optimal performance and quality of experience (QoE) for their subscribers even before mainstream deployment.

The animated avatar, developed by Slalom, renders on a cloud computing architecture, which is seamlessly integrated with the R&S CMX500. The R&S CMX500 emulates a 5G network to establish a Voice over New Radio (VoNR) connection to the end-user device. The end-user experience is brought to life using a Motorola Edge 40 Pro 5G smartphone connected to Lenovo ThinkReality A3 Smart Glasses, where the avatar is displayed. The system also features a loopback of audio samples, laying the groundwork for future audio quality assessments based on the POLQA algorithm. A key aspect of the avatar’s animation is head movement emulation, which is designed to convey attentiveness during calls. The accurate rendering and timely display of such details on the end-user device are among the key performance indicators that are being further investigated by both companies.

Christoph Pointner, Senior Vice President for Mobile Radio Testers at Rohde & Schwarz says: “We are thrilled to enhance our application testing capabilities through our collaboration with Slalom. This partnership lays a robust foundation for the wireless ecosystem, accelerating the market introduction of XR-based applications and services to pave the way for the metaverse.”

Sam Andrews, General Manager at Slalom says: “In partnership with Rohde & Schwarz, we have developed an innovative concept where we can assess and measure the end-to-end quality of XR experiences that considers network, device, and application to create seamless outcomes for end users and unlock new opportunities for enterprises.” Jason Inskeep, Advanced & Converged Architectures / Mobile / 5G at Slalom, adds: “At Slalom, we believe that being able to architect a true end-to-end integrated solution – from the network to the application layer to the end user – is fundamental to helping our customers achieve resiliency and efficiency at scale, unlock new revenue streams and create amazing customer experiences.”

This collaboration between Rohde & Schwarz and Slalom opens the way to virtual interactions that are more immersive and personal. For consumers, this innovation promises an enhanced sense of presence and engagement during voice calls.

Rohde & Schwarz and Slalom will demonstrate the test bed for AR-animated avatar calls at the Mobile World Congress 2024 at the Rohde & Schwarz booth 5A80 in hall 5 of Fira Gran Via in Barcelona.

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Anritsu Corporation a global provider of innovative test and measurement solutions now enable advanced AI (Artificial Intelligence) capabilities for solving difficult problems in wireless communications systems using DeepSig’s proven AI machine learning (ML) technology.  Radio Spectrum is a valuable asset that needs to be managed, shared, and utilized optimally in wireless networks.  New radio frequencies required to enable 6G Use Cases are becoming increasingly scarce, and there is increased attention towards the development of novel spectrum-sharing techniques.  Traditional RF sensing techniques face limitations in dynamically changing wireless environments, and more advanced monitoring and signal characterization is required.

Anritsu has addressed this challenge by partnering with Deepsig to deliver a groundbreaking solution that integrates the capabilities of the Anritsu MS2090A Field Master Pro Spectrum Analyser with DeepSig’s wireless signal detection and classification software, which is based on its patented Artificial Intelligence (AI) deep learning algorithms.  Employing a deep learning, data-driven approach allows Anritsu to rapidly incorporate new radio signal models into their capabilities using DeepSig’s ML training tools. RF signals of interest from diverse new sources like drones and IOT devices can be learned quickly and accurately in days, rather than months, to meet fast-changing customer requirements. These advanced technologies also form the foundation for AI-native RF sensing for 6G. This integrated solution will empower customers to enhance network performance, optimize spectrum utilization, and achieve real-time adaptation to changing RF conditions.

The post SmartViser and Anritsu unite to optimise testing for Energy Labelling regulation for smartphones and tablets with Strategic Partnership appeared first on ELE Times.

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Designers can leverage the newest U-blox modules to simplify cellular and IoT design.

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Improve your PCB designs and avoid costly respins due to EMC test failures by learning some basic design techniques and applying modern EMC analysis software.

Editor’s Note: This a four-part series of DIs proposing improvements in the performance of a “traditional” PWM—one whose output is a duty cycle-variable rectangular pulse which requires filtering by a low-pass analog filter to produce a DAC. This second part addresses the inability of “rail-to-rail” op amps’ output swing to encompass supply rail voltages.

Part 1 can be found here.

Recently, there has been a spate of design ideas (DIs) published that deal with microprocessor (µP)-generated pulse width modulators driving low-pass filters to produce DACs. Approaches have been introduced which address ripple attenuation, settling time minimization, and limitations in accuracy. This is the second in a series of DIs proposing improvements in PWM-based DAC performance. Each of the series’ part’s recommendations are, and will be, implementable independently of the others. This DI addresses the inability of “rail-to-rail” op amps’ output swings to encompass their supply rail voltages. Recognizing that an op amp is needed to buffer a filter from a DC load to prevent load-induced errors, and that these devices are useful in implementing more effective analog filters, there is a legitimate interest in mitigating or eliminating this imperfection.

Wow the engineering world with your unique design: Design Ideas Submission Guide

It don’t mean a thing if it ain’t got that swing (well, sort of…)

The common mode input voltages of many rail-to-rail op amps may be 100 mV above their positive and below their negative supply rails, but none have an output common mode voltage range which includes those rails. The OPA376, 2376, and 4376 rail-rail family with its excellent input offset voltage and bias current ratings are no different. The SC70-5, SOT23-5, and SO-8 package versions reach within 40 mV of the rails with a 10 kΩ load from -40°C to 125°C, and within 50 mV with a 2 kΩ load. There are various means of dealing with this limitation.

In the spirit of “Doctor, it hurts when I do this”, “Then don’t do that!”: software could simply prevent the setting of duty cycles which would drive the op amp too near a supply rail. This is rather unsatisfactory if the code which generates the duty cycle values expects that the values of zero and full scale (FS) will be executable. So, suppose an op amp can swing to within X mV of both its positive rail (VDD) and ground; instead of programing the PWM counter with a value of DC, program it with DC’ = DC · (1 – α) + α · FS/2, where α = X mV · 2 / VDD.

If that calculation imposes an unacceptable software burden, there is a related analog approach. In Figure 1, set R = r · α / (1 – α). The full range of DC values is now restricted to a range that the op amp output can replicate.

Figure 1 A purely analog means of avoiding op amp input voltages so close to the supply rails that the output cannot replicate them.

If the resistors have a 0.1% tolerance, the maximum offset error is a little greater than 2-15· VDD. The gain error is larger though: a little less than 2-10 · VDD. With adequate calculation resolution, the method of scaling the duty cycle count in software leads to smaller errors than the purely analog one.

In some applications, it is imperative that a DAC can swing to ground. In others, it must also be able to reach the µP’s positive rail, VDD. To accomplish this, voltage(s) beyond (a) supply rail(s) must be generated. But in no case can the supply voltages’ range exceed that recommended for the op amp, which is 5.5 V for the OPAx376 family. This necessitates different solutions for the common VDD supply values of 1.8, 2.5, 3.3 and 5.0 V. We will now follow with a series of schematics that contain solutions for each of these voltages…

The circuitry for the op amp positive rail (OP+) can be ignored in favor of VDD if the DAC needn’t swing to VDD. Texas Instruments’ LM7705 provides a complete and elegant means of generating a voltage that is only slightly more negative than ground, thereby allowing the op amp output to reach 0 V (Figure 2). This charge pump accepts a supply voltage of from 3 to 5.25 V and provides a regulated output of -230 mV at up to 20 mA. The LM7705 offer features beyond those of a simple charge pump inverter (which requires an external oscillator) in that:

1. An inverter sets the negative rail supply voltage to be the negative of the positive supply voltage. At VDD = 3 V and above, 3 V – (-3 V) exceeds the OPAx376’s family’s maximum differential supply voltage VOpRange of 5.5 V. The LM7705 provides just enough negative voltage and no more than is needed.
2. The LM7705 has a smaller footprint and incorporates an oscillator and a regulated DC output into a single IC.

Figure 2 This simple and inexpensive inverting charge pump provides a regulated -0.23 V for a rail-to-rail op amp’s negative supply so that the op amp output can swing to, and even below, ground.

But an application might also require swinging to the positive rail. The need to avoid supply voltage ranges exceeding 5.5 V for the OPAx376 leads to different solutions for different values of VDD (always assumed to be within +/- 5% of nominal value). The simplest solution is for the case of VDD equal to 1.8 V (Figure 3).

Figure 3 Solution for staying within the supply operating range for the OPAx376 where VDD = 1.8 V.

The LM2664 is a voltage inverter generating -VDD from + VDD. With the addition of D1, D2, C3 and C4, a voltage of 2 · VDD – 2 · Vd is generated where Vd is the voltage drop across the diodes. OA+ is enough above VDD to allow the op amp output to include the positive rail. The difference between OA+ and OA- is safely within supply operating range (VOpRange) for the OPAx376. If your VDD is between 1.8 and 5.5 V and is less than 1/3 of the VOpRange of your op amp, this simple and cheap circuit could be all you need. But if not…

As shown in Figure 4, the same circuit is the basis for operation from a 2.5V supply, but accommodations must be made to meet VOpRange for the OPAx376. This is accomplished by adding D3 and D4 to incur voltage drops.

Figure 4 Solution for staying within the supply operating range for the OPAx376 where VDD = 2.5 V.

Combinations of +/-5% variations in VDD, tolerances in diode voltage drops, and variations over temperature and load of the above circuit’s output voltages warn against applying the strategy of adding more diodes in series for the case where VDD increases to 3.3V (Figure 5).

Figure 5 Solution for staying within the supply operating range for the OPAx376 where VDD = 3.3 V.

Here the LM2664 performs the same function as it did for a VDD of 1.8 and 2.5 V. But it powers a cheap op amp IC which functions as a positive and a negative voltage regulator. The R6 / R7 divider ensures that the LM358BI operates within its common mode input range. (Its VOpRange is greater than 30 V!) OA+ and OA- voltages are approximately 100 mV beyond VDD = 3.3 V +/-5% and ground. Q1 and Q2 are placed in feedback loops to reduce the regulator output impedance. Since the op amp rails should be decoupled with ground-referenced .1 µF capacitors, this reduced impedance increases the loop’s high frequency break point. The result could be unstable were it not for the combination of C5 and R3 and that of C6 and R1. These pairs filter out the high phase-shift, high frequency feedback taken from the emitters and ensure that only mid frequencies down to DC are being regulated, thus establishing stability. In this circuit, the resistors are 1% tolerance parts.

As shown in Figure 6, the circuit for a 5 V VDD is similar to that for 3.3 V, but simpler. Here the higher Pump+ voltage means that there are no worries about input common mode operation, and we can dispense with R6 and R7. The passive components that make up the regulators are now identical.

Figure 6 Solution for staying within the supply operating range for the OPAx376 where VDD = 5 V.

Encompassing supply rail voltages

In this DI, several different approaches have been presented for producing DACs whose voltage swings encompass supply rails, or at least mitigate the problems associated with those that don’t. Hopefully, one or more are suitable for your application.

Christopher Paul has worked in various engineering positions in the communications industry for over 40 years.

Related Content

• Parsing PWM (DAC) performance: Part 1—Mitigating errors
• A simple, accurate, and efficient charge pump voltage inverter for $1 (in singles)
• Double up on and ease the filtering requirements for PWMs
• Optimizing a simple analog filter for any PWM

The post Parsing PWM (DAC) performance: Part 2—Rail-to-rail outputs appeared first on EDN.

Transphorm Inc of Goleta, near Santa Barbara, CA, USA says that it is showcasing its broad spectrum (low to high power) gallium nitride (GaN) power conversion solutions in booth 1813 at the Applied Power Electronics Conference (APEC 2024) in Long Beach, CA, USA (25–29 February), at which it is a Silver Partner...