Новини світу мікро- та наноелектроніки

This design idea revisits another: “PWM power DAC incorporates an LM317.” Like the earlier circuit, this one implements a power DAC by integrating an LM317 positive regulator into a mostly passive PWM topology. It exploits the built-in features of that time-proven Bob Pease masterpiece so that its output is proportional to the guaranteed 2% precision of the LM317 internal voltage reference and is inherently protected from overloading and overheating.

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

However, unlike the earlier design idea that requires a separate 15v DC power input, this remake (shown in Figure 1) adds a switching input boost preregulator so it can run from a 5v logic rail. The previous linear design also has a limited power efficiency that actually drops below single-digit percentages when driving low voltage loads. The preregulator fixes that by tracking the input-output voltage differential across the LM317 and maintains a constant 3v. This is the just adequate dropout-suppressing headroom for the LM317, minimizing wasted power.

Here’s how it works.

Figure 1 LM317 and HC4053 combine to make a PWM power DAC while Q1 forces preregulator U3 to track and maintain a constant 3v U2 I/O headroom differential to improve efficiency.

As described in the earlier DI, switches U1b and U1c accept a 10-kHz PWM signal to generate a 0v to 11.25v “ADJ” control signal for the U2 regulator via feedback networks R1, R2, and R3. The incoming PWM signal is AC coupled so that U1 can “float” on U2’s output. U1c provides a balanced inverse of the PWM signal, implementing active ripple cancellation as described in “Cancel PWM DAC ripple with analog subtraction.”

Note that R1||R2 = R3 to optimize ripple subtraction and DAC accuracy. This feedback arrangement makes U2’s output voltage follow this function of PWM duty factor (DF): 

Vout = 1.25 / (1 – DF(1 – R1/(R1 + R2))) = 1.25 / (1 – 0.9 DF),

as graphed in Figure 2.

Figure 2 Vout (1.25v to 12.5v) versus PWM DF (0 to 1) where Vout = 1.25 / (1 – 0.9 DF).

Figure 3 plots the inverse of  Figure 2, yielding the PWM DF required for any given Vout.

Figure 3 The inverse of Figure 2 or, the PWM DF required for any given Vout, where PWM DF = (1.111 – 1.389/Vout).

About that tracking preregulator thing: Control of U3 to maintain the 3v of headroom required to hold U2 safe from dropout relies on Q1 acting as a simple (but adequate) differential amplifier. Q1 drives U3’s Vfb voltage feedback pin to maintain Vfb = 1.245v. Therefore (where Vbe = Q1’s emitter-base bias):

Vfb/R7 = ((U2in – U2out) – Vbe)/R6
1.245v = (U2in – U2out – 0.6v)/(5100/2700)
U2in – U2out = 1.89 * 1.245v + 0.6v = 3v

Meanwhile, deducing what Q2 does is left as an exercise for the astute reader. Hint: It saves about a third of a wattage over the original DI at Vout = 12v. 

Note, if you want to use this circuit with a different preregulator with a different Vfb, just adjust:

R7 = R6 Vfb/2.4

In closing…

Thanks must go to reader Ashutosh for his clever suggestion to improve power DAC efficiency with a tracking regulator, also (and especially) to editor Aalyia for her creation of a Design Idea environment that encourages such free and friendly cooperation!

Stephen Woodward’s relationship with EDN’s DI column goes back quite a long way. Over 100 submissions have been accepted since his first contribution back in 1974.

 Related Content

• PWM power DAC incorporates an LM317
• Cancel PWM DAC ripple with analog subtraction
• A faster PWM-based DAC
• Parsing PWM (DAC) performance: Part 1—Mitigating errors
• Cancel PWM DAC ripple with analog subtraction but no inverter
• Parsing PWM (DAC) performance: Part 1—Mitigating errors
• Phased-array PWM DAC

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India’s Defence Research and Development Organisation (DRDO) continues to push the boundaries of indigenous defense innovation, with the DRDO Abhyas standing as a testament to this progress. Abhyas, a High-speed Expendable Aerial Target (HEAT) system, is designed to simulate realistic threat scenarios, providing the Indian Armed Forces with a cutting-edge platform for testing and training. True to its Sanskrit name, which means “practice,” Abhyas plays a crucial role in enhancing combat readiness by replicating aerial threats, enabling the evaluation of missile defense systems and other critical military technologies. Engineered to meet the evolving demands of modern warfare, this advanced UAV underscores India’s commitment to self-reliance in defense technology.

The DRDO Abhyas UAV is an expendable, high-speed aerial target that replicates a range of aerial threat profiles. It is an essential tool for training and testing defense personnel and weapon systems. The platform has been developed by the Aeronautical Development Establishment (ADE), a key laboratory under DRDO. The primary objective of Abhyas is to provide a cost-effective and reliable solution to simulate enemy aircraft, cruise missiles, and UAVs during military drills and equipment testing.

Abhyas boasts state-of-the-art technology, making it a versatile and efficient platform for defense applications. Key technical features include:

1. Airframe and Propulsion:
   
   • The UAV features a lightweight composite airframe designed for high-speed maneuvers.
   • It is powered by a small gas turbine engine capable of achieving high subsonic speeds, ensuring realistic simulation of aerial threats.
2. Guidance and Navigation:
   
   • Abhyas employs a Micro-Electro-Mechanical Systems (MEMS)-based Inertial Navigation System (INS) integrated with a Flight Control Computer (FCC).
   • This configuration allows the UAV to perform autonomous flight along pre-programmed paths with precision.
3. Launch and Recovery:
   
   • The system utilizes a rocket-assisted take-off mechanism, ensuring a quick and efficient launch.
   • Parachute-based recovery enables the safe retrieval of the UAV after mission completion.
4. Payload Capabilities:
   
   • Abhyas can be equipped with various payloads, including radar cross-section (RCS) augmentation devices, infrared (IR) flares, and electronic warfare (EW) systems, enhancing its ability to mimic diverse threat profiles.

The development of Abhyas has been a systematic process involving multiple stages of testing and validation:

• Initial Trials:The first successful trial of Abhyas was conducted in 2012, establishing proof of concept for its design and functionality.
• Subsequent Improvements:Over the years, DRDO has incorporated several enhancements, such as improved booster configurations and advanced augmentation systems for better simulation capabilities.
• Recent Achievements:In June 2024, DRDO conducted six consecutive trials at the Integrated Test Range (ITR) in Chandipur, Odisha. These trials validated the UAV’s endurance, reliability, and operational efficiency. Notably, two back-to-back launches within 30 minutes showcased its readiness for rapid deployment.

Abhyas serves a variety of roles in India’s defense ecosystem:

1. Missile Testing and Evaluation:
   
   • The UAV provides a realistic target for testing surface-to-air missiles (SAMs), air-to-air missiles (AAMs), and other defense systems, ensuring their operational readiness.
2. Training Exercises:
   
   • Abhyas aids in training defense personnel by simulating aerial threats, enhancing their combat preparedness and response strategies.
3. Electronic Warfare Training:
   
   • With its payload versatility, Abhyas can mimic electronic warfare scenarios, helping the armed forces test countermeasure systems.
4. Research and Development:
   
   • The platform’s modularity allows for the integration of experimental technologies, supporting ongoing R&D initiatives in defense.

1. Indigenous Development:
   
   • As an entirely Indian project, Abhyas reduces dependency on foreign technologies and contributes to the ‘Make in India’ initiative.
2. Cost-Effectiveness:
   
   • Being expendable, Abhyas provides a cost-efficient solution for large-scale training and testing exercises without compromising on performance.
3. Operational Versatility:
   
   • Its ability to simulate a wide range of threats makes it adaptable to various defense scenarios.
4. Ease of Deployment:
   
   • The UAV’s rocket-assisted launch and parachute recovery systems ensure quick deployment and turnaround times.

While Abhyas has proven to be a valuable asset, certain challenges remain:

• Limited Endurance:
  • As an expendable system, Abhyas has a limited operational lifespan, necessitating frequent replacements.
• Continuous Upgrades:
  • To stay relevant against evolving threats, the platform requires regular updates in terms of payload capabilities and performance metrics.

Looking ahead, DRDO plans to enhance the Abhyas platform further by integrating advanced artificial intelligence (AI) capabilities and improving its stealth characteristics. These upgrades aim to make the UAV more effective in simulating next-generation threats.

The DRDO Abhyas UAV represents a significant milestone in India’s journey towards self-reliance in defense technology. By providing a robust and flexible solution for testing and training, Abhyas not only strengthens the operational readiness of the Indian Armed Forces but also showcases the country’s capability to innovate in the field of unmanned systems. As DRDO continues to refine and expand the platform’s capabilities, Abhyas is poised to play an even more critical role in safeguarding India’s national security.

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The Defence Research and Development Organisation (DRDO) of India has been at the forefront of developing indigenous unmanned aerial vehicles (UAVs) to enhance the nation’s defense capabilities. A notable addition to this endeavor is the Archer UAV, a progression from the earlier Rustom series, tailored for both surveillance and combat roles.

The Archer UAV is an evolution of the Rustom-1 platform, which was initially designed for intelligence, surveillance, and reconnaissance (ISR) missions. Recognizing the need for a more versatile UAV capable of engaging in combat operations, DRDO initiated modifications to the Rustom-1, leading to the development of the Archer. This transformation began in mid-2022, focusing on equipping the UAV with weapon systems suitable for precision strikes.

The Archer UAV boasts impressive operational capabilities:

• Altitude: Capable of operating at altitudes up to 22,000 feet, allowing it to conduct missions above most ground-based threats.
• Endurance: With an endurance of 12 hours, it can perform extended missions without the need for frequent returns to base.
• Range: The UAV has a range of 220 kilometers, enabling it to cover substantial areas during operations.
• Payload Capacity: Designed as a multi-payload configurable system, the Archer can be equipped with various sensors and weaponry tailored to specific mission requirements.
• Autonomy: It features autonomous take-off and landing capabilities, even on short, semi-paved runways, enhancing its operational flexibility.

These specifications underscore the Archer’s versatility in both ISR and combat roles.

A significant advancement in the Archer’s design is its weaponization. The UAV has been modified to carry out armed missions, with the integration of weapon systems such as the Smart Anti-Airfield Weapon (SAAW) and Anti-Tank Guided Missiles (ATGMs). These modifications enhance its capability to perform precision strikes, making it a formidable asset in combat scenarios.

Building upon the success of the Archer, DRDO has developed the Archer-NG (Next Generation), a Medium-Altitude Long-Endurance (MALE) UAV. The Archer-NG features a single-engine, twin-boom pusher configuration and is designed to meet the specifications of the now-downgraded TAPAS program (previously known as Rustom-II). It shares common avionics, software, Ground Control Station (GCS), and Ground Data Terminal (GDT) with TAPAS, ensuring compatibility and reducing developmental redundancies.

The Archer-NG has an all-up weight of 1,700 kg and can carry up to 400 kg of payload, making it a versatile platform for armed missions. Its roles include Intelligence, Surveillance, Target Acquisition, and Reconnaissance (ISTAR), artillery target acquisition, battlefield post-strike assessment, and precision strikes. The UAV is equipped with an indigenous Ground Control Station capable of operating 6-7 UAVs simultaneously.

In a significant move towards bolstering India’s indigenous defense manufacturing capabilities, Bharat Electronics Limited (BEL) has been selected to manufacture 20 Limited Series Production (LSP) units of the Archer UAV. These units are slated for delivery to the Indian Army and Indian Air Force for user trials. The initial four units will be utilized for air-to-surface missile fire testing, with plans to integrate various weapon systems upon successful trials.

As of latest, the Archer-NG has completed high-speed taxi trials, with its maiden flight anticipated in February 2025, likely before the Aero India 2025 airshow at Yelahanka Air Force Station. The weaponized variant is expected to be completed within the next three years, with plans to integrate laser-guided rockets, bombs, and loitering munitions with ranges up to 100 km. The prototype is currently powered by an Austro Engine E4 powerplant inherited from the TAPAS-BH-201 program. However, two indigenous UAV engines of 180hp and 220hp are being developed by the Vehicle Research and Development Establishment (VRDE) to further enhance its capabilities.

The DRDO Archer UAV represents a significant milestone in India’s pursuit of self-reliance in defense technology. Its development from a surveillance platform to a weaponized UAV underscores the nation’s commitment to enhancing its aerial combat capabilities. With the upcoming advancements in the Archer-NG variant, India is poised to strengthen its position in the global UAV landscape, showcasing the prowess of its indigenous defense research and development.

The post DRDO Archer UAV: Advancing India’s Indigenous Combat Drone Capabilities appeared first on ELE Times.

New security standards for IoT devices are being released consistently, showing that security is no longer an afterthought in the design of embedded products. Last month, the White House launched the Cyber Trust Mark; a large move towards the security of IoT devices with a more robust concept of the “living label,” acknowledging the dynamic nature of security over time. The standard essentially requires prerequisite devices to be outfitted with a QR code that can be scanned for security information such as whether or not the device will have automatic software support such as security patches. Vendors of IoT products are now meant to partner up with an “accredited and FCC-recognized CyberLAB to ensure it meets the program’s cybersecurity requirements,” according to the FCC. 

In a conversation with Silicon Labs’ Chief Security Officer Sharon Hagi, EDN learned a bit more about this new standard, its history, and the potential future security application of this new QR code labelling scheme. 

In the IoT “boom” of the early 2000s that lasted well into the 2010s, companies were anxious to wirelessly-enable practically all devices, and when paired with the right MCU of choice, the applications seemed endless. Use cases from home automation and smart city to agritech and industrial automation were all explored, with supporting industry-specific or open protocols that could vary in spectrum (licensed or unlicensed), modulation technique, topology, transmit power, maximum payload size, broadcast schedule, number of devices, etc. With the growing hype and litany of hardware/protocol options, network security was still mostly discussed at the sidelines, leaving some pretty major holes for bad actors to exploit.  

With time and experience, it has become abundantly clear that IoT security is, in fact, pretty important. Undesirable outcomes like a Mirai botnet could lead to multiple IoT devices to be infected with malware at once allowing for larger-scale attacks such as distributed denial of service (DDoS). Moreover, a massive common vulnerability and exposure (CVE) found that lands a high score on the common vulnerability scoring system (CVSS) can potentially involve the US government’s cybersecurity and infrastructure security agency (CISA) and, if it’s not resolved, lead to fines. This is just adding insult to the reputational injury a company might experience with an exploited security issue. Sharon Hagi expands on IoT-device vulnerabilities, “these devices are in the field, so they’re subjected to different kinds of attack. There’s software-based attacks, remote attacks over the network, and physical attacks like side-channel attacks, glitching, and fault injection,” speaking towards how Silicon Labs included countermeasures for many of these attacks. The company’s initial developments in the area of security, namely centered around its “Secure Vault” technology with a dedicated security core with cryptographic functionality encapsulated within it. The core manages the root of trust (RoT) of the device, manages keys, and governs access to critical interfaces such as the ability to lock/unlock the debug port. 

Hagi went on to describe the background of the US cybersecurity standards that lead to the more recent regulatory frameworks, citing the NIST 8259 specification as the foundational set of cybersecurity requirements for manufacturers to be aware of (Figure 1). Another baseline standard is the ETSI european standard (EN) 303 645 for consumer IoT devices.

Figure 1 NIST 8259A and 8259B technical capabilities and non-technical support activities for manufacturers to consider in their products. Source: NIST

Hagi expanded more on the history of the Cyber Trust Mark, “The history of the Cyber Trust Mark kind of followed right after [the establishment of NIST 8259] in 2021 during the Biden administration with Executive Order 14028,” which had to do with security measures for critical software, “and that executive order  basically directed NIST to work with other federal agencies to further develop the requirements and standards around IoT cybersecurity.” He mentioned how this order specified the need for a labeling program to help consumers identify and judge the security of embedded products (Figure 2). 

Figure 2 NIST labeling considerations for IoT device manufacturers where NIST recommends a binary label that is coupled with a layered approach using either a QR code or a URL that leads consumers to additional details online. Source: NIST

“After this executive order, the FCC took the lead and started implementing what we now know as the Cyber Trust Mark program,” said Hagi, mentioning that Underwriter Laboratories (UL) was the de facto certification and testing lab for compliance with the US Cyber Trust Mark program as well as the requirements of the connectivity security alliance (CSA) with its product security working group (PSWG). 

In fact, the PSWG consists of over 200 companies with promoters that include tech giants like Google, Amazon, and Apple as well as OEMs such as Infineon, NXP Semiconductors, TI, STMicroelectronics, Nordic Semiconductor and Silicon Labs. The aim of the PSWG is to unite the disparate emerging regional security requirements including but not limited to the US Cyber Trust Mark, the Cyber Resilience Act (CRA) in the EU with the “CE marking”, and the Singapore Cybersecurity Label Scheme (CLS). 

Many of the companies within the PSWG have formulated their own security measures within their chips, NXP, for instance, has their EdgeLock Assurance program, and ST has their STM32Trust security framework. TI has an allocated product security incident response team (PSIRT) that responds to reports of security vulnerabilities for TI products while Infineon created a Cyber Defense Center (CDC) with a corresponding Computer Security Incident Response Teams (CSIRT/CERT) and PSIRT team for the same purpose. Hagi stated that Silicon Labs set itself apart by implementing security “down to the silicon level” in product design early on in the IoT development game. 

These wireless SoCs and MCUs are the keystone of the IoT system, providing the intelligent compute, connectivity, and security of the product. Using more secure SoCs will inevitably ease the process of meeting the ever-changing security compliance standards. Engineers can choose to enable features such as secure boot, secure firmware updates, digitally signed updates with strong cryptographic keys, and anti-tampering, to ultimately enhance the security of their end product. 

Perhaps the most interesting aspect of the interview were the potential applications of these labeling schemes and how to make them more user-friendly. “The labeling scheme could be compared to a food label,” said Hagi, “You go to the supermarket, take the product off the shelf and it shows you the ingredients and nutritional value and make a decision on whether or not this is something you want to buy.” In the future, a more objectively secure product could be a more pricey option to the more basic alternative, however it would be up to the consumer to decide. While this analogy served its purpose, its similarities ended there. While the label contains all “ingredients” of security built into the product, the Cyber Trust Mark is not meant to be static, since vulnerabilities can still be discovered well after the product is manufactured. 

“You might be able to see the software bill of materials (SBOM) where maybe there is a certain open source library that the product is using and there is a vulnerability that has been reported against it. And maybe, when you get home, you need to update the product with new software to make sure that the vulnerability is patched,” said Hagi as he discussed potential use cases for the label.  

The hardware BOM (HBOM) may also be very relevant in terms of security, bringing into light the entire supply chain that is involved in assembling the end product. The overall goal of the label is to incentivize companies to foster trust and accountability with transparency on both the SBOM and HBOM. 

Hagi continues to go down the checklist of security measures the label might include, “What is the original and development history of the product’s security measures? Can it perform authentication? If so, what kind of authentication? What kind of cryptography does it have? Is this cryptography certified? Does the manufacturer include any guarantees? At what point will the manufacturer stop issuing security updates for the product? Does the product contain measures that would comply with people in specific jurisdictions?” These regional regulations on security do vary between, for instance, the EU’s General Data Protection Regulation (GDPR) and of course, the US Cyber Trust Mark. 

ML brings on another dimension of security considerations to these devices, “The questions would then be what sort of data does the model collect? How secure are these ML models in the device? Are they locked? Are they unlocked? Can they be modified? Can they be tampered with?” The many attributes of the models bring other levels of security considerations with them and avenues of attack. 

Ultimately putting this amount of information on a box is impossible, even more pertinent is how users are meant to interpret the sheer amount of information. Consumers were more than likely to not really understand all the information on a robust security label, even if it was human-readable. “Another angle is providing some sort of API so that an automated system can actually interrogate this stuff,” said Hagi. 

He mentioned one example of securely connecting devices from different ecosystems, “Imagine an Amazon device connecting to an Apple device, with this API, security information is fetched automatically letting users know if it is a good idea to connect the device to the ecosystem.” 

As it stands, the labelling scheme is meant to protect the consumer in more of an abstract sense, however it might be difficult for the consumer to accurately understand the security measures put into the product. In order to make full use of a system like this, “it is likely that a bit of automation is necessary for consumers to make appropriate decisions just in time.” This could eventually enable consumers to make informed decisions on product purchasing, replacement, upgrades, connection to a network, and the security risks when throwing out an item that could contain private information in its memory. 

Aalyia Shaukat, associate editor at EDN, has worked in design publishing industry for six years. She holds a Bachelor’s degree in electrical engineering from Rochester Institute of Technology, and has published works in major EE journals as well as trade publications.

Related Content

• Navigating IoT security in a connected world
• Understand the hardware dependencies of IoT security
• 6 core capabilities an IoT device needs for basic cybersecurity
• 7 steps to security for the Internet of Things

The post The future of cybersecurity and the “living label” appeared first on EDN.

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India’s electronics manufacturing industry is experiencing rapid growth, driving a rising demand for high-performance reflow ovens—critical for soldering surface-mount components onto printed circuit boards (PCBs). To meet this demand, several Indian companies specialize in manufacturing and supplying reflow ovens, catering to both domestic and global markets. Here’s a look at some of the leading reflow oven providers in India.

1. Heller India

Heller India, a subsidiary of Heller Industries, is renowned for its advanced reflow soldering ovens. The company offers a range of products, including convection reflow soldering ovens, voidless/vacuum reflow soldering ovens, formic/fluxless reflow soldering ovens, pressure curing ovens, vertical curing ovens, and magazine curing ovens. Their reflow ovens are designed to meet the demands of surface-mount technology (SMT) reflow, semiconductor advanced packaging, consumer electronics assembly, and power device packaging. Heller India emphasizes efficiency and sustainability in its products, featuring low-height top shells, Industry 4.0 compatibility, and innovative flux management systems.

2. Leaptech Corporation

Based in Mumbai, Leaptech Corporation offers a comprehensive range of SMT equipment, including reflow soldering ovens. They are authorized distributors of ITW EAE Vitronics Soltec’s Centurion Reflow Ovens, known for their superior reliability and thermal performance. The Centurion platform features forced-convection SMT reflow systems with tight, closed-loop process control, suitable for high-throughput PCB assembly environments. Available in various zone configurations, these ovens cater to diverse production requirements. Leaptech also provides Tangteck reflow ovens, which include SMT reflow furnaces (IR & hot air), BGA soldering reflow furnaces, and curing or drying furnaces.

3. EMS Technologies

Located in Bengaluru, EMS Technologies specializes in manufacturing reflow ovens and other SMT equipment. Their product lineup includes the Konark 1020, a 10-zone reflow oven designed to cater to versatile industry needs and complex PCB types. The Konark 1020 features a PC with Windows 10 operating system, data logging traceability, adjustable blower speed, and PID closed-loop temperature control. The machine is equipped with 10 heating zones and 2 cooling zones, offering flexibility in manufacturing and higher throughput.

4. Mectronics Marketing Services

Headquartered in New Delhi, Mectronics Marketing Services provides a variety of electronic manufacturing equipment, including reflow soldering systems. They offer EPS reflow ovens designed with patented Horizontal Convection technology for even heating across the entire face of the PCB. Their product range includes traditional bench-top solder reflow ovens, batch ovens, automatic floor-style systems, hot plates, and vapor phase ovens, catering to various production scales and requirements.

5. Bergen Associates Pvt. Ltd.

Also located in New Delhi, Bergen Associates offers a range of PCB assembly equipment, including reflow ovens. They cater to both small-scale and large-scale manufacturing requirements, providing solutions that meet diverse industry needs.

6. NMTronics India Pvt. Ltd.

With offices across major cities, NMTronics is a leading provider of electronic manufacturing solutions. They supply reflow ovens from renowned global manufacturers, ensuring high-quality equipment for their clients. Their offerings are suitable for various production scales and are known for their precision and efficiency.

7. Sumitron Exports Pvt. Ltd.

Headquartered in New Delhi, Sumitron Exports provides a variety of soldering solutions, including reflow ovens. They represent several international brands and offer advanced reflow soldering systems to the Indian market, catering to the needs of modern electronics manufacturing.

8. Accurex Solutions Pvt. Ltd.

Based in Bengaluru, Accurex Solutions specializes in providing SMT and PCB assembly equipment. Their product lineup includes advanced reflow ovens designed for precision soldering, meeting the demands of high-quality electronics production.

9. Maxim SMT Technologies Pvt. Ltd.

Located in Pune, Maxim SMT Technologies offers a variety of SMT equipment, including reflow soldering machines. They focus on delivering high-performance solutions to meet the demands of modern electronics manufacturing, ensuring efficiency and reliability in their products.

10. Technosys Equipments Pvt. Ltd.

Headquartered in Bengaluru, Technosys Equipments provides a range of electronic manufacturing equipment, including reflow ovens. They emphasize innovation and quality in their product offerings, catering to various industry requirements.

These companies play a significant role in supporting India’s electronics manufacturing industry by providing reliable and advanced reflow soldering solutions. Their contributions ensure that manufacturers have access to the necessary equipment to produce high-quality electronic products efficiently.

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India’s drone industry has witnessed significant growth, driven by advancements in technology and a surge in demand across various sectors such as defense, agriculture, and infrastructure. Several companies have emerged as leaders in drone manufacturing and services, offering innovative solutions tailored to diverse applications. Here are the top 10 drone camera companies in India as of 2025:

1. IdeaForge Technology Pvt. Ltd.

Founded in 2007 by IIT Bombay alumni, IdeaForge is a pioneer in India’s UAV industry. The company specializes in designing and manufacturing drones for defense, homeland security, and industrial applications. Notable products include the Netra, a micro UAV designed for surveillance and reconnaissance missions, and the Switch UAV, known for its long-endurance capabilities. In December 2023, IdeaForge ranked 5th globally in the dual-use category (civil and defense) as per a report by Drone Industry Insights.

2. Asteria Aerospace Limited

Established in 2011 and headquartered in Bengaluru, Asteria Aerospace focuses on developing drones for defense and industrial applications. The company offers products like the A200, which received India’s first micro category drone certification in October 2022, and the A200-XT and A410-XT, both certified by the Directorate General of Civil Aviation (DGCA). Asteria also launched SkyDeck, a cloud-based drone operations platform that provides services such as flight planning, data processing, and AI-based analysis.

3. Garuda Aerospace

Based in Chennai and founded in 2015, Garuda Aerospace offers drone solutions across various sectors, including agriculture, disaster management, and defense. The company provides custom drones, sensors, and software for aerial surveys, mapping, and inspections. Garuda has collaborated with organizations like ISRO for delivering medicines and food using drones and has been active in disaster relief efforts, such as assisting in rescue operations during the Uttarakhand avalanche in 2021. Indian cricketer Mahendra Singh Dhoni is its brand ambassador and shareholder.

4. Skylark Drones Pvt. Ltd.

Skylark Drones provides drone-based solutions for industries like agriculture, mining, and construction. Their offerings include autonomous drones, custom payloads, and mapping software. The company has partnered with leading firms such as Tata Power and Mahindra & Mahindra to implement drone-based solutions, enhancing operational efficiency and data accuracy.

5. Aarav Unmanned Systems Pvt. Ltd.

Headquartered in Bangalore, Aarav Unmanned Systems specializes in manufacturing drones for defense and commercial applications. Their product lineup includes the Nayan series for surveillance and the Cheetah series for aerial surveys and mapping. Notably, Aarav has developed a drone-based delivery system for medical supplies and emergency response services, successfully tested in collaboration with the Karnataka government.

6. Aero360

Based in Delhi, Aero360 offers a range of drone services, including aerial surveys, mapping, and photography. The company has developed proprietary software capable of processing drone data to generate accurate 3D models and maps. Aero360 has collaborated with major companies like Larsen & Toubro and the Adani Group to provide drone-based solutions for various projects.

7. Sagar Defence Engineering Pvt. Ltd.

Located in Pune, Sagar Defence Engineering focuses on providing drone solutions for defense and homeland security applications. Their Garuda series drones are designed for high-altitude, long-endurance missions, suitable for surveillance and reconnaissance. The company has also developed a drone-based anti-poaching system, tested in partnership with the Maharashtra forest department.

8. Vignan Technologies Pvt. Ltd.

Operating out of Hyderabad, Vignan Technologies offers drone solutions for agriculture, mining, and construction industries. Their products include custom drones, agricultural sensors, and mapping software. The company has developed a precision agriculture system that provides farmers with real-time data on soil moisture, temperature, and other critical parameters to enhance crop yields.

9. Omnipresent Robot Technologies Pvt. Ltd.

Based in Bangalore, Omnipresent Robot Technologies provides drone solutions for industrial inspection and maintenance. Their offerings include custom drones, sensors, and software designed to inspect infrastructure such as buildings and pipelines. The company has partnered with industry leaders like Reliance Industries and Larsen & Toubro to implement drone-based inspection solutions.

10. Tata Advanced Systems Limited (TASL)

A subsidiary of Tata Sons, TASL is involved in aerospace and defense manufacturing. The company has agreements with Israel Aerospace Industries and Urban Aeronautics for the co-development of UAVs in India. TASL has developed and successfully flight-tested a long-range kamikaze drone known as the ALS-50, capable of striking targets beyond 50 km and returning if the mission is aborted. This drone is set to be inducted into the Indian armed forces.

These companies exemplify the rapid advancement of drone technology in India, offering a range of products and services that cater to both domestic and international markets. Their innovations are contributing significantly to sectors such as defense, agriculture, infrastructure, and emergency response, positioning India as a key player in the global drone industry.

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For many variable resistor (rheostat) applications, one of the device’s terminals is connected to a voltage source VS. Such a source might be a reference DC voltage, an op amp output carrying an AC plus DC signal, or even ground. If freed from the constraint of (programmable) “floating” rheostats satisfied by recently disclosed solutions in “Synthesize precision Dpot resistances that aren’t in the catalog” and “Synthesize precision bipolar Dpot rheostats,” there is a compelling alternative approach. Yes, it’s slightly simpler in that it avoids MOSFETs, and that the +5V supply for the digital potentiometer is the only supply needed (especially if rail-to-rail input and output op-amps are employed.) But more importantly, it’s distinct in that it exhibits no crossover distortion when there is a change in the sign of an AC signal between terminals A and VS.

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

As seen in Figure 1, I’m shamelessly appropriating the same digital pot used in those other solutions. (Note the limited operating voltage range of potentiometer U2.)

Figure 1 A basic programmable rheostat leveraging the same digital pot used in other solutions.

The resistance between terminals A and voltage source VS looking into terminal A is res = R1/(1 – αa·α2·αb) where the alphas are the gains of U1a, U2, and U1b respectively. αa and αb are slightly less than unity at DC, falling in value with loop gain as frequency increases. α2 is equal to one of the numerator integers 0, 1, 2… 256 divided by a denominator of 256 as determined by the programming of U2.

By changing the numerator from 0 to 255, it would appear that resistor value ratios of 1:256 could be achieved. Unfortunately, U2’s integral non-linearity (INL) is specified as ± 1 LSB. Strictly following this spec, operation with a numerator of 255 could drive the value of res close to infinity at DC and so should be avoided. But that’s not the only concern. For an α2 numerator value “num”, a resistance error factor EF of roughly ± 1/(256-num) could be encountered because of the ± 1 LSB accuracy. To minimize uncertainty, num should be held to less than some maximum value (solutions in “Synthesize precision Dpot resistances that aren’t in the catalog” and “Synthesize precision bipolar Dpot rheostats” have similar problems for small values of “num”). Another reason for such a limit is that resistance resolution is much better with lower than higher values of “num”. For instance, the ratio of resistor values with numerators of 10 and 11 is 1.004. But the values of 240 and 241 yield a ratio of 1.07, and those of 250 to 251, 1.2.

The simple addition of U3 and R2 in the Figure 2 circuit mitigates these problems by reducing the required maximum value of “num”. For R2 greater than R1, resistances between R1 and R2 should be implemented by having analog switch U3 select R1 rather than R2. For larger resistances, R2 should be selected.

Figure 2 Enhanced programmable rheostat that mitigates the uncertainties problems of the basic programmable rheostat by reducing the required maximum value of “num”.

To see why Figure 2 offers an enhancement, consider a requirement to provide resistance over the range of 1k to 16k. In Figure 1 and Figure 2 circuits, R1 would be 1k. To produce a value of 1k, “num” would be 0. For 16k, “num” in Figure 1 would be 240, yielding a maximum EF of ± 1/(256 – 240) or approximately 6.3%. But in Figure 2, resistance values of 4K and above would be derived by having U3 switch R1 out in place of a 4k R2. The maximum required value of “num” would be 192, and EF would be reduced by a factor of 4 to 1.6%. It will also be seen that the Figure 2 circuit significantly relaxes op-amp performance requirements for limiting the errors due to finite open loop gains. To see this, some analysis is necessary. Given the maximum allowed fractional resistance error (OAerr) introduced by the op-amp pair, it can be seen that:

Therefore, for closed loop op amp gains:

At DC, op amp voltage follower closed loop gain α is 1/(1-1/a0L), where a0L is the op amp open loop DC gain. To satisfy requirements at DC:

Matters are more complicated with AC signals. At a frequency f Hz, the voltage follower open loop gain HOLG(j·f) is 1 / (1/A0 + j·f/GBW), where GBW is the part’s gain-bandwidth product and j = √-1.

The closed loop gain HCLG(j·f) is 1/( 1 + 1/ HOLG(j·f)). Substitution of HCLG(j·f) for αa and αb in Equation (1) yields a fourth order polynomial due to the real and imaginary terms of HCLG(j·f). It’s easier to solve the problem with a simulation in LTspice than to solve it algebraically.

LTspice offers a user-specifiable op-amp called…well, “opamp”. It can be configured for user-selected values of a0L and GBW. The tool is configured as shown in Figure 3 to solve this problem.

Figure 3 LTspice can be used to determine op-amp requirements for an AC signal application.

The a0L value required for AC signals will be larger than that calculated in equation (3). It’s suggested to start with an a0L default value of 10000 (100 dB) and try different values of GBW. Use the results to select an op amp for the actual circuit and either simulate it if a model exists or at least update the simulation with the minimum specified values of a0L and GBW for the selected op amp.

Table 1 shows some examples of the behaviors of the circuit with different idealized op-amps. It’s clear that DC performance in either circuit is not a challenge for almost any op-amp. But it’s also evident that the AC performance of a given op-amp is notably better in the Figure 2 circuit than in that of Figure 1, and that a given error can be achieved with a lower performance and less costly op-amp in the Figure 2 circuit.

Table 1 Examples of the circuits’ behavior producing 16kΩ with various op-amp parameters.

The approach taken in Figure 2 can be generalized by supporting not just two but four or more different resistors. Doing so further minimizes both op-amp performance requirements and worst-case errors by reducing the maximum required value of “num”. It also extends the range of resistor values achievable for a given error budget.

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

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