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Пам’яті Старостіна Максима Олександровича

Новини - 4 hours 36 min ago
Пам’яті Старостіна Максима Олександровича
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KPI4U-1 чт, 06/05/2025 - 16:50
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На війні загинув студент нашого університету Старостін Максим Олександрович (17.06.2005– 03.06.2025).

📰 Газета "Київський політехнік" № 23-24 за 2025 (.pdf)

Новини - 4 hours 46 min ago
📰 Газета "Київський політехнік" № 23-24 за 2025 (.pdf)
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Інформація КП чт, 06/05/2025 - 16:40
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Вийшов 23-24 номер газети "Київський політехнік" за 2025 рік

КПІ ім. Ігоря Сікорського — Почесний освітній партнер Huawei

Новини - 6 hours 9 min ago
КПІ ім. Ігоря Сікорського — Почесний освітній партнер Huawei
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kpi чт, 06/05/2025 - 15:18
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Нещодавно у Huawei відбулася важлива подія — 25 років діяльності компанії в Україні. З нагоди цього університет був відзначений спеціальною нагородою "Honorable educational partner".

Renesas abandoning SiC production plans amid Chinese price war and Wolfspeed uncertainty

Semiconductor today - 6 hours 10 min ago
According to a report by Nikkei, Renesas Electronics Corp of Tokyo, Japan is abandoning its plans to produce silicon carbide (SiC) power semiconductors for electric vehicles (EVs), due to slowing growth in the EV market — coupled with a supply glut driven by increased production from Chinese manufacturers — that has led to falling prices...

На війні загинув випускник нашого університету Листопад Володимир Анатолійович

Новини - 6 hours 51 min ago
На війні загинув випускник нашого університету Листопад Володимир Анатолійович
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kpi чт, 06/05/2025 - 14:36
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Із сумом повідомляємо, що стало відомо про загибель на війні Листопада Володимира Анатолійовича 13.06.1985 – 23.05.2025.

Micro-gravity manufacturing firm Space Forge to be CISM’s first incubation client

Semiconductor today - 10 hours 8 min ago
Swansea University has signed a deal that makes Space Forge Ltd of Cardiff, South Wales, UK (which is pioneering space-based advanced materials manufacturing via fully returnable satellites) the first firm to be physically hosted in the Centre for Integrative Semiconductor Materials (CISM), where it will undertake work on manufacturing in micro-gravity. Space Forge will be CISM’s first incubation client with a dedicated cleanroom incubation bay and access to a full suite of semiconductor processing and characterization tools...

A quick and practical view of USB Power Delivery (USB-PD) design

EDN Network - 10 hours 35 min ago

USB Power Delivery (USB-PD) now offers faster, more efficient, and more versatile power handling solutions. As we can all see, it’s an exciting advancement that significantly enhances the capabilities of USB connections.

This mechanism uses the USB configuration channel (CC) to allow a device to request a specific voltage. While this might seem complex at first, it’s pretty easy to utilize in practice.

Figure 1 The module has several jumpers to set the DC output voltage at multiple levels. Source: Author

What makes it easy nowadays is that we can buy compact USB-PD Trigger/Decoy modules that do the complicated background tasks for us (Figure 1). You can see such a module has a number of jumpers to set the DC output voltage to 5 V, 9V, 12 V, 15 V or 20 V.

This module acts as a trigger or decoy to request specific power profiles from USB-PD power sources such as USB-C chargers, power banks, and adapters. So, with this module, you can trigger USB-PD protocols and thus, for example, charge your laptop via a PD-capable USB-C power supply.

Note at this point that a USB-PD Trigger, sometimes called a USB-PD Decoy, is a small but clever circuitry that handles the USB-PD negotiation and simply outputs a predefined DC voltage.

Some USB-PD Trigger/Decoy modules are adjustable with a selector switch, or cycle among voltages with a pushbutton press, while others deliver a fixed voltage, or will have solder jumpers (or solder pads to install a fixed resistor) to select an output voltage. The output connection points on these modules are typically just two bare solder pads, or small screw terminals in certain cases (Figure 2).

Figure 2 The output connection points are shown on the modules. Source: Author

For just a few bucks each, these smaller and slenderer USB-PD Trigger/Decoy modules are useful to have in your tool chest, both for individual projects and for use in a pinch. In my view, for most applications, the fixed voltage type power provider is preferable, as this prevents accidental slips that could destruct the power consumer.

I recently bought a set of these fixed voltage modules. As you can see, the core part of these single-chip modules is the IP2721 USB Type-C physical layer protocol IC for USB Type-C input interfaces.

Figure 3 IP2721 is a USB Type-C PD protocol IC for USB input port that supports USB Type-C/PD2.0/PD3.0 protocols. Source: Author

The USB Type-C device plug-in and plug-out process is automatically detected based on CC1/CC2 pins. The chip has an integrated power delivery protocol analyzer to get the voltage capabilities and request the matched voltage.

Figure 4 The schematics shows a design use case built around the USB Type-C PD protocol IC. Source: Injoinic Technology

Surprisingly, the newly arrived module—designed for a single, fixed-voltage output—features the IP2721 controller in a bare minimum configuration without the power-pass element.

Figure 5 The module features the IP2721 controller in a bare minimum configuration. Source: Author

Hence, the output voltage will be whatever VBUS is, and this could be 5 V during initial enumeration or stay at this voltage in case negotiations failed. Luckily, for many applications, this will not be much of an issue. But on paper, to comply with the USB power delivery specifications, the device is supposed to have a high-side power MOSFET as the power-pass element to disconnect the load until a suitable power contract has been negotiated.

For this writing, I needed to test the output of my module. So, below you can see a little snap taken during the first test of my IP2721 USB-PD trigger 9-V module; nothing but the process of testing the module with a compatible power source and a DC voltmeter.

Figure 6 DV voltmeter shows the output of the IP2721-based USB-PD module. Source: Author

Here are some final notes on the power delivery.

  • USB-PD is a convenient way of replacing power supply modules in many electronics projects and systems. Although USB-PD demands specialized controller chips to be utilized properly, easily available single-purpose USB-PD Trigger/Decoy modules can be used in standalone systems to provide USB-PD functionality.
  • Interestingly, legacy USB can only provide a 5-V power supply, but USB-PD defines prescriptive voltages such as 9 V, 15 V, and 20 V in addition to 5 V.
  • Until recently, the USB-PD specification allowed for up to 100 W (5 A@20 V) of power, called Standard Power Range (SPR), to flow in both directions. The latest USB-PD specification increases the power range to 240 W (5 A@48 V), called Extended Power Range (EPR), through a USB-C cable. So, if a device supports EPR expansion commands, it can use 28 V, 36 V, and 48 V.
  • Since the most recent USB-PD specification allows to realize up to 240 W power delivery through a single cable, it’s possible to provide ample power over USB to multiple circuit segments or devices simultaneously.
  • Electronic marking is needed in a Type-C cable when VBUS current of more than 3 A is required. An electronically marked (E-Marked) cable assembly (EMCA) is a USB Type-C cable that uses a marker chip to provide the cable’s characteristics to the Downstream Facing Port (DFP). It’s accomplished by embedding a USB PD controller chip into the plug at one or both ends of the cable.
  • The USB-PD Programmable Power Supply (PPS) was implemented with USB PD3.0. With PPS, devices can gradually adjust the current (50-mA steps) and voltage (20-mV steps) in the range from 5 V to 20 V. PPS can directly charge a battery, bypassing the battery charger in a connected device.
  • Adjustable Voltage Supply (AVS) was implemented with USB PD3.1 and extended with PD3.2, allowing it to work within SPR below 100 W, down to a minimum of 9 V. AVS is similar to PPS in terms of function, but the difference is that it does not support current-limit operation, and the output voltage is adjusted in 100-mV steps in the range from 9 V to 48 V.

Note that USB-PD, which is combined with USB-C, takes full advantage of the power supply and multi-protocol functions over USB-C. Implementing USB-C for portable battery-powered devices enables them to both charge from the USB-C port as well as supply power to a connected device using the same port.

So, devices using a single or multicell battery charger can now be paired with a USB-C or USB PD controller, which enables the applications to source and sink power from the USB-C port. Below is an application circuit based on MP2722, a USB Type-C 1.3 compliant, highly integrated, 5-A, switch-mode battery management device for a single cell Li-ion or Li-polymer battery.

Figure 7 The application circuit is built around a 5 A, single-cell buck charger with integrated USB Type-C detection. Source: Monolithic Power Systems (MPS)

In the final analysis, it’s important to recall that the USB-PD is not just about the power delivery-related negotiations. Feel free to comment if you can help add to this post or point out issues and solutions you have found.

T. K. Hareendran is a technical author, hardware beta tester, and product reviewer.

Related Content

The post A quick and practical view of USB Power Delivery (USB-PD) design appeared first on EDN.

Mouser Electronics Named 2024 Distributor of the Year by Bulgin

ELE Times - 12 hours 12 min ago

Mouser Electronics, Inc. announced that it has been named 2024 Distributor of the Year by Bulgin, a leading manufacturer of environmentally sealed connectors and components for various industries, including automotive, industrial, medical and more. Representatives for Bulgin cited Mouser’s strategic support of new product launches and customer growth in 2024.

“Mouser is a valued partner, and we congratulate the Mouser team on this well-deserved award, which celebrates Mouser’s customer service, effective communication, and commitment to meeting our business needs and goals,” said Eric Smith, Vice President of Global Distribution Channel with Bulgin. “Mouser played a key role in contributing to our overall success in 2024, and we look forward to continuing the momentum in 2025 and beyond.”

“We’d like to thank Bulgin for this great honor. This award recognizes our continued efforts to be the industry’s New Product Introduction (NPI) leader, with the latest products from forward-thinking companies like Bulgin,” said Krystal Jackson, Vice President of Supplier Management at Mouser. “We have an outstanding business relationship with Bulgin and anticipate great success together in the future.”

The post Mouser Electronics Named 2024 Distributor of the Year by Bulgin appeared first on ELE Times.

Sharing where I spend most of my time

Reddit:Electronics - 14 hours 45 min ago
Sharing where I spend most of my time

Doing my masters in EE while working full time as a flight software engineer. Always something to keep me busy

submitted by /u/new_account_19999
[link] [comments]

Improved fully analog modular Grid-Tie/On-Grid MPPT solar power inverter - Still not isolated so beware, feel free to ask any questions or offer suggestions

Reddit:Electronics - 20 hours 58 min ago
Improved fully analog modular Grid-Tie/On-Grid MPPT solar power inverter - Still not isolated so beware, feel free to ask any questions or offer suggestions

This is my second version of a fully analog modular Grid-Tie solar power inverter.

Video of testing and building the inverter: https://www.youtube.com/watch?v=wP2KDP2ekxw

BEWARE, this design still uses the Buck-Boost topology, which means there is no galvanic isolation between the input and the output, touching any terminal of the solar panels WILL hurt you. Keep this in mind.

Since my Last Version that I also posted here on Reddit I've took many of the helpful comments and warnings into consideration when designing this new version.

Links to OSHW Lab projects:

Main Board: https://oshwlab.com/radiohonza/1200wgridtiebasev1_copy_copy_copy
Power conversion module: https://oshwlab.com/radiohonza/9910gridtiebuckboostv1_copy_copy
Polarity switcher module: https://oshwlab.com/radiohonza/4q-rectifier-v1_copy
Control module: https://oshwlab.com/radiohonza/gridtiecontrolv1_copy_copy
MPPT module: https://oshwlab.com/radiohonza/gridtiempptv1_copy_copy_copy

Main improvements include:

  • Independent thermal protection on each power conversion module implemented as a CV sensitivity decrease at high temperatures (automatic power balancing between modules, second to last image shows worst case scenario behaviour)
  • Power conversion modules are controlled via an external CV, output current shaping etc is all contained on the module offering up to 125 W continuous output power with 91 % efficiency when delivering into 230 VAC power grid.
  • Grid overvoltage protections, both peak and mean value sensing
  • Grid frequency sensing to prevent islanding (parasitic grid forming)
  • Power modules are built using an aluminum core PCB, which greatly improves cooling
  • Power module CV distribution optimization to improve efficiency at low powers by diving modules into 3 groups and first ramping each group to roughly 30 % power (peak module efficiency) after which all groups continue the rest of the way
  • Improved polarity switcher/4Q rectifier/unfolding stage modules, each capable of delivering up to 2.5 Arms continuously into the power grid or serve 4x power conversion modules (4x125W = 500 W each)
  • Non-resettable thermal fuse for each polarity switcher module disconnecting the power grid in case of overtemperature
  • Improved MPPT module with thermal compensation of the wattmeter section (tracking performance can be seen on last image showing a screenshot of an oscilloscope sensing input voltage ripple and input power ripple to draw the solar panel PV diagram, symetric concave curve indicates basically perfect tracking)
  • Input and output common mode noise filtering
  • Input and output passive overvoltage protections, MOVs and GDT+fast fuse on the input
  • Optional control current input for limiting inverter power (eg. to prevent outflow of energy etc.)
  • No exotic ICs or custom wound inductors are used, EVERYTHING is off-the-shelf and usually available from mutiple different manufacturers
  • Everything is modular, so only the Main board determines the maximum power capability.

Feel free to ask any questions or offer suggestions.

submitted by /u/MrSlehofer
[link] [comments]

3 wire to 2 wire turn signal/brake combiner circuit

Reddit:Electronics - Wed, 06/04/2025 - 23:32
3 wire to 2 wire turn signal/brake combiner circuit

Most cars here in Europe have their rear turn signals as separate amber bulbs.
In N. America, it's common to utilize the respective side brake light for this function.
I designed a circuit which will take the three inputs (L, Brake, and R) and combine them into outputs for the left and right brake light only.

In the picture I used cabochon lights from Halloween special effects to simulate. Works perfectly... now.
I had an issue where one of the tiny glass diodes broke, and I think it's because I had a 12v source charging a 680uF capacitor through it... A sudden burst of current.
I removed the small glass diodes and replaced them with a couple of beefy silicon rectifier diodes, and the issue was resolved.

I didn't have a SPDT relay, so I used a DPDT relay, and simply bridged both sides to act as a SPDT relay. This has the other benefit of doubling the current carrying capability.

In my original circuit layout, I had added another relay so that this circuit could be bypassed, restoring original functionality.
This is why there are three relays instead of only two on the layout plan.
I actually designed this circuit years ago, and it was before I knew the terms common, normally closed and normally open, so the relay contacts are labeled E for energized and R for relaxed being connected to the common pin.

submitted by /u/One-Cardiologist-462
[link] [comments]

WIN launches linearity optimized 0.12µm GaN power process

Semiconductor today - Wed, 06/04/2025 - 21:54
WIN Semiconductors Corp of Taoyuan City, Taiwan — which provides pure-play gallium arsenide (GaAs) and gallium nitride (GaN) wafer foundry services for the wireless, infrastructure and networking markets — has launched its NP12-1B, a 0.12μm gate-length depletion-mode (D-mode) GaN high-electron-mobility transistor (HEMT) technology on silicon carbide (SiC) substrates...

Чек-лист корупціогенних факторів: що це і для чого

Новини - Wed, 06/04/2025 - 17:52
Чек-лист корупціогенних факторів: що це і для чого
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kpi ср, 06/04/2025 - 17:52
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У КПІ ім. Ігоря Сікорського впроваджено важливий інструмент, що сприяє формуванню прозорого середовища в університеті – чек-лист корупціогенних факторів.

Cheap DC power supply for breadboards

Reddit:Electronics - Wed, 06/04/2025 - 17:35
Cheap DC power supply for breadboards

I got an power adapter of an old notebook, so I used it to build a power supply for breadboards using a DC-DC converter with XL4016 together with a display to show voltage and current, packed in a plastic box for cooked food. Simple but effective!

submitted by /u/Livio63
[link] [comments]

Original K2-W vacuum-tube opamp

Reddit:Electronics - Wed, 06/04/2025 - 17:20
Original K2-W vacuum-tube opamp

For all the other analog-lovers out there here's my K2-W opamp.
I can't say for sure but I think it's vacuum tubes are original (they are also marked GAP/R) and the datasheet appears to be original as well.
The datasheet in particular is just so cool, it reads much more informally than what I am used to seeing these days. In the application examples specifically it reads as though the author is excited about the prospects of this tool and I can't blame them, I would have been as well.

Anyway, hope you all enjoy this. I'll get a proper-scan of the datasheet at work tomorrow and post it here for those interested.

submitted by /u/NamasteHands
[link] [comments]

Electronic components

Reddit:Electronics - Wed, 06/04/2025 - 16:53
Electronic components

Brand new original DSPIC30F2010-30I/SP

submitted by /u/Linkunze
[link] [comments]

5G-Powered V2X: Using Intelligent Connectivity to Revolutionize Mobility

ELE Times - Wed, 06/04/2025 - 15:19

Vehicle-to-Everything (V2X) communication systems and lightning-fast 5G networks are merging to usher in a new era of global mobility. We are getting closer to the promise of safer roads, autonomous driving, and intelligent traffic ecosystems as a result of this convergence, which is changing how cars interact with their surroundings. Tech pioneers like Jio, Alepo, and Keysight Technologies are at the forefront of this change, facilitating V2X implementation across many infrastructures and regions.

V2X: What Is It?

The term “vehicle-to-everything” (V2X) refers to a broad category of technologies that allow automobiles to interact with their surroundings. Networks (V2N), pedestrians (V2P), infrastructure (V2I), other vehicles (V2V), and connected devices (V2D) are all included in this. Every mode has special features that improve driver ease, traffic efficiency, and road safety.

Thanks to vehicle-to-vehicle (v2v) communication, cars can exchange vital information, including direction, speed, and braking condition. This makes collision avoidance systems and early alerts easier, especially in low-visibility situations. Vehicle-to-infrastructure (V2I) enables automobiles to communicate with traffic lights, smart city systems, and road signs. By alerting drivers about impending risks or real-time signal changes, it facilitates traffic planning.

A proactive, as opposed to reactive, transportation system is made possible by the network of intelligent contacts created by this variety of communication channels. An environment where traffic flows are optimized, accidents are reduced, and cars can operate with more autonomy is the end outcome.

The Impact of Jio on India’s V2X Market Dependency

One of India’s top telecom companies, Jio, is actively constructing a strong 5G infrastructure to support V2X in the nation going forward. Jio’s V2X platform aims to create a digital transportation environment in which cars are intelligent, networked machines that can make decisions in real time.

Jio claims that their 5G-based V2X solutions are designed to make important applications like smart traffic control, cooperative collision avoidance, and autonomous driving possible. These uses make extensive use of 5G’s ultra-low latency and high bandwidth characteristics, which enable almost immediate device-to-device communication.

Road safety is still a major concern in India, where Jio’s effort has the potential to be revolutionary. Roadside unit (RSU) deployment and network slicing for V2X services allow the platform to serve latency-sensitive applications, such as danger detection and emergency vehicle prioritising. Additionally, Jio’s efforts are in line with India’s larger goal of developing intelligent transportation systems under the framework of Digital India.

Alepo’s 5G Core: An Expandable C-V2X Backbone

Alepo’s 5G Converged Core platform introduces software-defined intelligence to the V2X space, while Jio’s focus is on connectivity and infrastructure. Alepo’s basic product is capable of managing V2X-specific subscriptions, Quality of Service (QoS) policies, and session orchestration. It also supports the cellular V2X (C-V2X) standard.

Alepo’s platform stands out by enabling two distinct C-V2X communication pathways—PC5 for direct communication and Uu for network-assisted transmission. Direct communication, which allows peer-to-peer transmission between vehicles without requiring a cellular network, usually operates in the 5.9 GHz ITS frequency. In scenarios where milliseconds count, such as platooning or high-speed highway synchronisation, this is crucial.

On the other hand, network-based communication links cars to cloud services and other organisations by leveraging the cellular infrastructure that is already in place. Alepo’s 5G core skillfully strikes a balance between these modes to guarantee uninterrupted connection in any setting.

Alepo’s system’s user equipment (UE) classification is another essential component. Vehicles and pedestrians are distinguished by the system as distinct UE kinds, each with its own QoS characteristics. This makes it possible to handle data requirements and mobility patterns in a tailored way, guaranteeing that a pedestrian warning is handled differently from a vehicle coordination signal. For a sophisticated V2X ecosystem to be supported at scale, this degree of granularity is essential.

The Testing and Validation Ecosystem of Keysight

Thorough validation is essential to the efficacy of V2X systems, and Keysight Technologies is essential in this regard. Testing for compliance and interoperability must change to keep up with the complexity of V2X devices. This need is met by Keysight’s SA8700A C-V2X Test Solution, which supports both protocol and RF testing according to 3GPP Release 14 guidelines.

Manufacturers and developers may validate their V2X devices in controlled laboratory settings thanks to this service. End-to-end simulation of real-world situations, including lane-change assistance, junction collision warnings, and emergency braking alerts, is supported. Keysight’s technologies guarantee that devices not only function but also function under stress, thanks to their comprehensive diagnostic feedback and latency measurements.

Furthermore, Keysight provides the WaveBee V2X Test and Emulation package, which is intended to replicate actual driving situations on test roads and tracks. From early development to field testing after deployment, these solutions provide ongoing validation across the product lifecycle. These testing platforms guarantee user safety, performance, and compliance as international laws tighten and safety-critical applications gain traction.

Obstacles in the Way of V2X Maturity

While the promise of V2X is vast, its full-scale deployment is hindered by several critical hurdles. Standardisation is a significant obstacle. The global automotive landscape is fragmented, with regional preferences varying between technologies like DSRC and C-V2X. To guarantee smooth communication between automobiles made by various manufacturers, these standards must be harmonised.

Privacy and security are important issues to consider. As cars are becoming data nodes, it is important to ensure private data is protected from abuse or leakage. V2X networks need to implement secure authentication methods, end-to-end encryption, and anomaly detection methods to maintain resilience and trust.

Investment in infrastructure is another issue. It is critical to densify roadside units, edge servers, and network slicing in order for V2X systems to provide the best experience. Governments and municipalities need to engage in making smart mobility infrastructure happen and, while telecom has its role through networks and infrastructure developments, the effort must come from all parties. 

Conclusion: It’s Closer Than You Think

Right now, in the transportation space, parts of the ecosystem are finally being redesigned through the fusion of 5G and a new V2X communication standard. At the junction of connectivity with safer cars, smarter roads, and seamless transportation, companies like Jio, Alepo, and Keysight have already begun shaping that future.

As infrastructure continues to grow, and standardization becomes more advanced, V2X will go from a specialized innovation to an essential part of urban mobility. This technology could change everything from increasing safety by lowering traffic deaths to building networks of autonomous vehicles. The time has come for urban planners, politicians, telecom, and automotive industry players to partner up and together invest in V2X.

 

The post 5G-Powered V2X: Using Intelligent Connectivity to Revolutionize Mobility appeared first on ELE Times.

Fraunhofer IAF develops semi-automated manufacturing process for cost-efficient resonantly tunable quantum cascade laser modules

Semiconductor today - Wed, 06/04/2025 - 14:27
Resonantly tunable quantum cascade lasers (QCLs) are high-performance laser light sources for a wide range of spectroscopy applications in the mid-infrared (MIR) range. Their high brilliance enables minimal measurement times for more precise and efficient characterization processes and can be used, for example, in chemical and pharmaceutical industries, medicine or security technology. Until now, however, the production of QCL modules has been relatively complex and expensive...

10-octave linear-in-pitch VCO with buffered tri-wave output

EDN Network - Wed, 06/04/2025 - 14:03

Frequent contributor Nick Cornford recently assembled an ensemble of cool circuit designs incorporating linear-in-pitch VCOs (LPVCOs). 

These elegant and innovative designs (standard fare for Nick’s contributions) were perfectly adequate for their intended applications. Nevertheless, it got me wondering how difficult it would be to implement an LPVCO with a range covering the full 10-octave audio spectrum, from 20 Hz to 20 kHz. I even decided to try for extra credit by going for a tri-wave output suitable for direct drive of one of Nick’s famous squish-diode sine converters. Figure 1 shows the result.

Figure 1 An LPVCO with 10-octave (20 Hz to 20 kHz) tri-wave output comprises antilog pair Q1 and Q2, two-way current mirror Q3 and Q4, integrator A1b, comparator A1a, and buffer A1c. Resistors R1 and R2 are precision types, and T1 is a Vishay NTCSC0201E3103FLHT (inhale!).

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

Vin is scaled by the tempco-compensating voltage divider, ((R1+T1)/R2 + 1) = 28:1, and applied to the Q1 and Q2 antilog pair, where Q1 level shifts and further temperature compensates it. Then, with the help of buffer A1c, it’s antilogged and inverted by Q2 to produce Ic2 = 2(2Vin) µA = 1 µA to 1 mA for Vin = 0 to 5v.

From there, it goes to the two-way current mirror: Q3 and Q4. A description of how the TWCM works can be found here in “A two-way mirror—current mirror that is.”

The TWCM passes Ic2 through to the integrator A1b if comparator A1a’s output is zero, and mirrors (inverts) it if A1a’s output is high. Thus, A1b ramps up if A1a’s output is at 0v, and down if it’s at 5v, resulting in sustained oscillation.

The C1 timing ramp has a duration in each direction ranging from 25 ms (for Vin = 0) to 25 µs (for Vin = 5v). The triangular cycle will therefore repeat at Fosc = 2(2Vin)µA/(25nCb)/2 = 20(2(2Vin) ) Hz.

 So, there’s the goal of a tri-wave LPVCO with an output span of 20 Hz to 20 kHz centered at 640 Hz, and it wasn’t so terribly messy to get there after all!

My thanks go to Nick Cornford for introducing the LPVCO to Design Ideas (DIs), and to Christopher Paul and Andy I for their highly helpful simulations and constructive criticisms of my halting steps to temperature-compensating antilogging circuits. I also thank editor Aalyia Shaukat for her DI environment that makes such teamwork possible for a gang of opinionated engineers, and mostly accomplished without actual bloodshed! 

Mostly.

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.

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The post 10-octave linear-in-pitch VCO with buffered tri-wave output appeared first on EDN.

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