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I think I salvaged it from an old VCD player. Pretty cool. submitted by /u/BobBolzac [link] [comments]

Some background here https://antiqueradios.com/forums/viewtopic.php?t=306396 "Prior to the introduction of integrated op amps, it was extremely difficult to build stable DC amplifiers. By passing the signal through a chopper, the DC voltage can be passed through a feedback stabilized AC amplifier and then converted back to DC afterward. Chopper stabilized DC amplifiers--using electromechanical devices--have been around since the late 1940s at least." "HP's photoconductive choppers eliminated the inevitable problems with contact adjustment and wear in the electromechanical ones, but they required higher input voltages to overcome the "on" resistance of the photocells." Enjoy! submitted by /u/99posse [link] [comments]

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Науково-технічні конференції на ПБФ набирають обертів kpi пт, 06/27/2025 - 17:22

Участь КПІ ім. Ігоря Сікорського у панельній дискусії щодо розвитку наукових парків в Україні kpi пт, 06/27/2025 - 16:41

SuperLight Photonics of Enschede, the Netherlands — a spin-off from the University of Twente that is developing a photonic integrated circuit (PIC) wideband laser light source for measurement and detection applications — has unveiled the SLP-1050 compact, high-performance light source, purpose-built for demanding high-speed measurement applications...

Motivations for bolstering backup

Last March, I documented my travails striving to turn a 2018-era x86-based Apple Mac mini into a workable system in spite of its diminutive, non-upgradeable 128 GByte SSD’s internal capacity:

Eight months later (last November), I discussed how, motivated by the lightning-induced last-summer demise of one of my network-attached storage (NAS) devices:

I actualized longstanding aspirations to bolster my backup stratagem in order to better protect my precious data from failed hardware and other catastrophes (a virus or hack, for example).

Updating the initial approach

This writeup acts as an update to the initial approaches (and results) that I documented in the two prior pieces. Available-capacity optimization first. For pretty much the entirety of the time I’d owned the Mac mini, each time I needed to install an update to the currently installed version of MacOS and/or the Safari browser, I’d first temporarily need to uninstall a few particularly large apps to free up sufficient SSD space, then install the update, and then reinstall the apps afterwards. This got, as you can probably imagine, really tedious really quickly.

Salvation came by accident. Microsoft is pushing users to convert from the “Legacy (also referred to as “Classic”) Outlook” PIM (personal information management) app, along with the “Mail”, “Calendar”, and “People” apps originally bundled with Windows 10, to “New Outlook”. The latter successor is a PWA (progressive web app) that, simplistically speaking, acts as a locally installed “wrapper” for the cloud-based version of Outlook. Since the initial public release of “New Outlook” a couple of years ago, Microsoft has evolved the Windows variant of the app to optionally support local storage of some-to-all user data, thereby enabling access when offline. The MacOS version, conversely, still does only limited, temporary local caching.

Why is this important? As Microsoft has increasingly focused its development attention on “New Outlook”, I’d been noticing an increasing prevalence of bugs in “Legacy Outlook”, along with lengthening delays until they were eventually fixed. A month or so ago, after upgrading my MacBook Pro to MacOS 10.15 “Sequoia”, I also noticed that the “Legacy Outlook” search facility (which leverages Apple’s Spotlight system service) was no longer giving me results. Frustrated, I decided to “throw in the towel” and switch to “New Outlook” instead. I eventually ended up switching back to “Legacy Outlook”, after realizing that the lack of a locally stored full sync of my database would be unpalatable for offline use while traveling, for example (after doing so, by the way, Spotlight-based Outlook search magically started working again). But in the process, I learned something that in retrospect should have been obvious (but then again, what isn’t?).

After converting to “New Outlook”, I came across a settings option to delete “Legacy Outlook” data. Doing so freed up nearly 30 GBytes of storage capacity. This improvement was a nice-to-have on my laptop, which has a 512 GByte SSD (with ~25% still free even after converting back to “Legacy Outlook”). On the Mac mini, which I subsequently also converted to “New Outlook” and where the “Legacy Outlook” database represented ~25% of the SSD’s total capacity, it was a fundamental breakthrough. Regarding the database’s formidable size and in my (slight) defense:

• I use Outlook for my “day job’s” multiple accounts’ emails, contacts and calendars
• I’ve been employed there for three months shy of 14 years as I write this
• Note that this payload includes not only emails (and calendar entries and contacts) but also email file attachments, which in my organization are frequent and can be sizeable
• I’m an admitted digital packrat (which has saved me numerous times in the past, as I’ve been able to pull up archived content to substantiate or refute my own memory)

Due in part to the storage capacity savings (alas, unlike with my Mozilla Firefox and Thunderbird profiles, for examples, there doesn’t seem to be a straightforward way to relocate the “Classic Outlook” profile to an external drive), coupled with the fact that the Mac mini is perpetually sitting on my desk and connected to broadband (and that if broadband goes down, my email-related productivity won’t be the only thing that suffers), I’ve kept “New Outlook” on it. The freed-up room on the SSD enabled me to also full-version upgrade the Mac mini from MacOS 10.14 “Mojave” to MacOS 10.15 “Sequoia”, delivering another (modest, in my case) benefit.

As with Adobe Creative Suite, which lets you optionally install apps to a different (attached, obviously) storage device (as long as you install them one at a time, that is), with MacOS 10.15 you can optionally install App Store-sourced programs elsewhere as long as they’re 1 GByte or larger in size…because, after all, Apple doesn’t want to discourage you from buying more profitable-to-them computers with larger internal storage capacities, right? In my particular case, that relocation was only relevant for Luminar AI, 2.64 GBytes in size. But I’ll take it.

Backup Expansion

Last November’s write-up on storage backup showcased the “3-2-1 rule”. Here again is Wikipedia’s concise summary:

The 3-2-1 rule…states that there should be at least 3 copies of the data, stored on 2 different types of storage media, and one copy should be kept offsite, in a remote location (this can include cloud storage). 2 or more different media should be used to eliminate data loss due to similar reasons (for example, optical discs may tolerate being underwater while LTO tapes may not, and SSDs cannot fail due to head crashes or damaged spindle motors since they do not have any moving parts, unlike hard drives). An offsite copy protects against fire, theft of physical media (such as tapes or discs) and natural disasters like floods and earthquakes.

That said, as I noted then in the introduction to my stratagem explanation:

As you’ll see in the paragraphs to follow, I’m not following the 3-2-1 rule to the most scrupulous degree—all of my storage devices are HDD-based, for example, and true offside storage would be bandwidth-usage prohibitive with conventional home broadband service.

While I can’t vouch for what storage technologies my more recently added “cloud” backup providers are using, they are off-site, so I feel pretty good about that. First off there’s my four-drive QNAP TS-453Be NAS, which, as I mentioned last time, holds “my music and photo libraries, along with decades’ worth of other accumulated personal files”:

The other two NASs on my LAN are purely used for backup purposes (both from computer sources and of each other’s contents), so losing them isn’t the end of the world. But the TS-453Be’s stored information is pretty darn important. What I learned is that QNAP’s HBS 3 Hybrid Backup Sync utility supports backups not only to USB- and Ethernet-connected local external storage but also to a variety of “cloud” storage services, among them Microsoft OneDrive. Also, since mine’s an Office 365 Family plan, I can associate it with up to five additional Microsoft accounts (beyond my own), each of which gets up to 1 GByte of OneDrive storage.

So, I created a second Microsoft account for myself, associated with a different email address of my many, and with its OneDrive storage capacity devoted exclusively to TS-453Be backups. HBS 3 backups are incremental—files that haven’t changed since the previous backup aren’t unnecessarily backed up again—so the bandwidth (and destination storage) “hit” wasn’t excessive after the initial backup session. I do one “cloud” backup a month (LAN backups are weekly), further limiting the incremental impact on my monthly 1.2 TByte usage allocation from Comcast/Xfinity (with added-cost unlimited usage always an option if ever needed). And I run them at midnight, when slumber means I don’t notice their LAN-bandwidth packet presence.

The other particularly important storage device here at the home office is the SSD inside my current “daily driver” computer, a 2020-era x86-based 13” Apple MacBook Pro.

Here, my cloud storage solution involves a highly regarded service called Backblaze, whose periodic Drive Stats storage reliability reports I’ve mentioned before. At the end of last year, Backblaze ran a promotion on its Personal Backup service tier: two years for $151.20 (normally $189), with Extended Version History (enabling access to older backed-up versions of files, too) also included. The incremental-backup Backblaze client app constantly runs silently in the background and by default focuses its attention only on data files, to optimize both its use of cloud storage and upload bandwidth, and under the assumption that you can reinstall programs if necessary. Except for the initial backup, along with the ~30 GByte data file outcome of my previously mentioned more recent reinstall of “Classic Outlook”, bandwidth usage has been scant. And functionality has to date been flawless. Highly recommended!

Thoughts on the concepts I introduced in my first two posts and augmented with this one? Sound off in the comments!

—Brian Dipert is the Editor-in-Chief of the Edge AI and Vision Alliance, and a Senior Analyst at BDTI and Editor-in-Chief of InsideDSP, the company’s online newsletter.

Related Content

• Workarounds (and their tradeoffs) for integrated storage constraints
• Beefing up backup
• Lightning strikes…thrice???!!!
• Fairly evaluating HDD reliability
• Apple’s fall 2024 announcements: SoC and memory upgrade abundance

The post Computer and network-attached storage: Capacity optimization and backup expansion appeared first on EDN.

Microchip has added secure code signing, firmware over-the-air (FOTA) updates, and CRA compliance to its ECC608 TrustMANAGER authentication IC. Additional enhancements include remote management of firmware images, cryptographic keys, and digital certificates. These capabilities help developers meet the cybersecurity requirements of the European Union’s Cyber Resilience Act (CRA) and prepare for similar regulations expected to emerge in other regions.

The ECC608 TrustMANAGER pairs with Kudelski IoT’s keySTREAM Software as a Service (SaaS) to securely store and manage cryptographic keys and certificates across IoT ecosystems. FOTA services support real-time firmware updates, enabling remote vulnerability patching and helping devices comply with evolving cybersecurity regulations.

Further enhancing cybersecurity compliance, Microchip’s WINC1500 Wi-Fi network controller in the TrustMANAGER development kit is now RED-certified for secure, reliable cloud connectivity. The EU’s Radio Equipment Directive (RED) sets strict requirements for network security, data protection, and fraud prevention. Starting August 1, 2025, all wireless devices sold in the EU must meet RED cybersecurity rules.

The ECC608 TrustManager is available for purchase from Microchip and its authorized distribution partners.

TrustManager product page

Microchip Technology 

The post Authentication IC strengthens IoT security appeared first on EDN.

The SKY63104/5/6 family of jitter-attenuating clocks and the SKY62101 clock generator simultaneously generate ultra-low jitter clocks for synchronous Ethernet and spread-spectrum PCIe. Built on Skyworks’ fifth-generation DSPLL and MultiSynth technologies, these devices support flexible input-to-output frequency mapping and enable single-IC clock tree designs for demanding networking, data center, and industrial applications.

Typical DSPLL RMS jitter is as low as 18 fs (12 kHz–20 MHz at 625 MHz), with total output jitter around 55 fs RMS—well suited for 224G PAM4 Ethernet SerDes. The devices also meet spread spectrum clocking requirements for PCIe Gen 1 through Gen 6.

The jitter attenuators and clock generator provide 12 outputs in a compact 8×8-mm QFN package with wettable flanks. The SKY63104 includes one DSPLL with two MultiSynths; the SKY63105 has two DSPLLs and one MultiSynth; and the SKY63106 features three DSPLLs with no MultiSynth. Output frequencies span 8 kHz to 3.2 GHz, with configurable formats including LVDS, HCSL, LVPECL, LVCMOS, S-LVDS, and CML. Output-to-output skew is tightly controlled at ±50 ps, with per-output delay adjustable in 50-ps steps.

SKY63104/5/6 product page 

SKY62101 product page 

Skyworks Solutions 

The post Clock ICs drive low-jitter Ethernet and PCIe appeared first on EDN.

EPC Space has announced the EPC7030MSH, a radiation-hardened 300-V GaN FET for high-voltage, high-power space applications. It supports front-end DC/DC converters in satellite power systems, power conversion for high-voltage distribution buses, and electric propulsion platforms requiring high-performance switching.

With a maximum RDS(on) of 35 mΩ and a typical gate charge of 25 nC (30 nC max), the EPC7030MSH delivers a continuous drain current of 50 A at 5 V and a single-pulse drain current of 150 A for 300 µs. According to EPC Space, these specifications place it among the highest-performing rad-hard FETs in its class.

The EPC7030MSH is rated for 300-V operation at a linear energy transfer (LET) of 63 MeV·cm²/mg and maintains single-event effect (SEE) immunity up to 250 V at an LET of 84.6 MeV·cm²/mg. It is also immune to total ionizing dose (TID) effects under both low and high dose rate conditions.

Engineering models of the EPC7030MSH cost $236 each in quantities of 500 units, while rad-hard space-qualified devices are priced at $349 each.

EPC7030MSH product page

EPC Space 

The post Space-ready GaN FET endures harsh radiation appeared first on EDN.

ST’s L9800 combines eight low-side drivers with diagnostics and protection in a compact leadless package for tight automotive spaces. The ISO 26262 ASIL-B-compliant device drives resistive, capacitive, or inductive loads—such as relays and LEDs—in body-control modules, HVAC systems, and power-domain controls.

Output channels can be controlled via the SPI port or two dedicated parallel inputs that map to selected outputs. These inputs enable emergency hardware control of two default channels even if the digital supply voltage is not available. This allows the L9800 to enter limp-home mode, maintaining essential safety and convenience functions during system failures, such as microcontroller faults or supply undervoltage.

The L9800 enhances vehicle reliability with real-time diagnostics and per-channel protection against open-circuit, short-circuit, overcurrent, and overtemperature faults. Diagnostic signals are accessible over the SPI bus, which also allows access to internal configuration registers for device setup. Additionally, the driver ensures safe operation during engine cranking, supporting battery voltages as low as 3 V.

Housed in a 4×4-mm TFQFN24 package, the L9800 low-side driver costs $0.52 each in lots of 1000 units.

L9800 product page 

STMicroelectronics

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xMEMS is bringing its µCooling fan-on-chip platform to AI-driven extended reality (XR) smart glasses. The silicon-based solid-state micro cooling chip provides localized, precision-controlled active cooling from within the glasses frame—without compromising form factor or aesthetics.

As smart glasses integrate more advanced AI processors, cameras, sensors, and high-resolution displays, total device power (TDP) is expected to rise from today’s 0.5–1 W to 2 W and beyond. This increase pushes more heat into the frame materials that rest directly against the skin, exceeding what passive heat sinking can effectively dissipate.

According to xMEMS, thermal modeling and physical verification of µCooling in smart glasses operating at 1.5 W TDP has demonstrated a 60–70% improvement in power overhead, allowing up to 0.6 W additional thermal margin. It also showed up to a 40% reduction in system temperatures and up to a 75% reduction in thermal resistance.

Built on a piezoMEMS architecture with no motors or bearings, the fan chip delivers silent, vibration-free operation in a package as small as 9.3×7.6×1.13 mm. 

µCooling samples for XR smart glasses are available now, with volume production planned for Q1 2026. To learn more about xMEMS active µCooling, click here.

xMEMS Labs

The post Solid-state fan chip reduces heat in XR glasses appeared first on EDN.

I always thought that if a circuit worked and passed basic functionality tests, you were good to go. But I’ve been digging deeper while working on a small consumer electronics project, and wow, there’s a whole other layer around safety, durability, and compliance that I hadn’t even considered. Things like how a device holds up under voltage fluctuations, or how materials react to heat and moisture, all that stuff matters a lot, especially if you’re thinking about scaling or selling internationally. I know there are experts like QIMA who offer this kind of testing, and it’s wild how many factors are involved. Makes me look at everyday devices differently now. **image not mine** submitted by /u/Poseidon_9726 [link] [comments]

🕔 Дайджест актуальних подій та конкурсів від Відділу академічної мобільності kpi пт, 06/27/2025 - 07:00

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

Fabless company Wise-integration of Hyeres, France — which was spun off from CEA-Leti in 2020 and designs and develops digital control for gallium nitride (GaN) and GaN IC-based power supplies — has released to production its first fully digital controller, WiseWare 1.1 (WIW1101), based on a 32-bit MCU. This enables high-frequency operation up to 2MHz, unlocking what are claimed to be new levels of power density, efficiency and form factor in compact AC–DC power converters...

КПІ ім. Ігоря Сікорського співпрацюватиме з N-iX kpi чт, 06/26/2025 - 16:36

Getting signals into an oscilloscope or digitizer without distorting them is a significant concern for instrument designers and users. The critical first point in an instrument is the input port. Oscilloscopes offer 50-Ω and 1-MΩ input terminations for both channels and trigger inputs. When should each be used?

A typical oscilloscope offers input ports terminated in either a 50-Ω, DC-coupled, or 1-MΩ AC- or DC-coupled, or ground (Figure 1).

Figure 1 The input coupling choices for a typical oscilloscope include 50-Ω DC, 1-MΩ AC or DC, and ground. Source: Art Pini

Input termination

The 50-Ω termination is intended for use with 50-Ω sources connected to the oscilloscope using a 50-Ω coaxial cable. The 50-Ω input properly terminates the coaxial cable, preventing reflections and associated signal losses.

The 50-Ω input termination is also used with certain probes. The simplest probe, based on a 50-Ω termination, is the transmission line or low-capacitance probe (Figure 2).

Figure 2 The low capacitance probe is intended to probe low impedance sources like transmission lines. A 10:1 attenuation is achieved by making RIN equal 450 Ω, which results in a 10:1 attenuation of the probed signal. Source: Art Pini

The transmission line probe has a relatively wide bandwidth, typically ranging from 5 GHz or more. Its input impedance is low, and in the case of a 10:1 probe, it is only about 500 Ω. Most other active high-bandwidth probes also utilize the 50-Ω oscilloscope input termination.

The 1-MΩ input termination is intended to connect to 10:1 high-impedance passive probes as shown in Figure 3.

Figure 3 A simplified schematic for a 10:1 high impedance passive probe connected to an oscilloscope’s 1 MΩ input. Source: Art Pini

The high-impedance probe places a 9-MΩ resistor in series with the oscilloscope’s 1-MΩ input termination, forming a 10:1 attenuator. This passive probe has a DC input resistance of 10 MΩ. The compensation capacitor (Ccomp) is adjusted so that the time constants Rin*Cin are the same as Ro*(Co+Ccomp), forming an all-pass filter offering a relatively square low-frequency pulse response. The 1-MΩ termination also serves as a high-impedance input for low-frequency measurements, where reflections are not an issue.

50-Ω vs 1-MΩ inputs

The two input terminations have significant differences. Consider the Teledyne LeCroy HDO 6104B, a 1 GHz mid-range oscilloscope, as an example (Table 1).

Input Termination	Bandwidth	Coupling	Vertical Range (V/div)	Offset Range	Maximum Input
50 Ω	1 GHz	DC, GND	1 mV to 1 V	± 1.6 V to ±10 V	5 Vrms, ± 10 V p-p
1 MΩ	500 MHz	AC, DC, GND	1 m V to 10 V	± 1.6 V to ± 400 V	400 V(DC + Peak AC<10 kHz)

Table 1 The characteristics of the input terminations are quite different. Source: Art Pini

The bandwidth of the 50-Ω termination is usually much greater than that of the 1-MΩ termination. In this example, it is 1 GHz. The oscilloscope’s bandwidth is generally specified for the 50-Ω termination. The 50-Ω input has a more limited input voltage range than the 1-MΩ input. The maximum voltage range of the 50-Ω termination is power-limited to 5 Vrms by the ½-watt rating of the input resistor. The 1-MΩ has a maximum voltage rating of 400 V (DC+AC peak <10 kHz). The 50-Ω input is only available in DC-coupled mode, whereas the 1-MΩ termination is available in both AC and DC-coupled modes. Finally, the offset range of the 1-MΩ input extends up to ±400 V while the 50-Ω offset range is ±10 V.  

DC or AC input coupling

DC coupling applies to the entire frequency spectrum of the signal’s frequency components from DC to the full rated bandwidth of the instrument’s specified input. AC coupling filters out the DC by placing a blocking capacitor in series with the oscilloscope input. The series capacitor acts like a high-pass filter.

In most oscilloscopes, the AC-coupled input has a lower cutoff frequency of about 10 Hz. AC-coupling the 50-Ω termination would require about 20,000 times larger capacitors to achieve the same 10-Hz lower cutoff frequency, so it is not done. This ability to separate a signal’s AC and DC components is utilized in applications such as measuring ripple voltage at the power supply’s output. The AC coupling blocks the power supply’s DC output while passing the ripple voltage. Figure 4 compares an AC- and a DC-coupled waveform with an offset voltage.

Figure 4 A 1 MHz, 381 mVpp, signal with a 100-mV DC offset is acquired using both DC (top trace) and AC (lower trace) coupling. Source: Art Pini

The upper trace shows the DC-coupled waveform. Note that the DC offset shifts the AC component of the input signal upward while the AC signal, shown in the lower trace, has a zero mean value. The AC coupling has removed the DC offset.

The peak-to-peak amplitude is measured using measurement parameter P1 as 381 mV. They are identical because the offset of the DC-coupled signal is canceled by the subtraction operation used in calculating the peak-to-peak value.

The DC-coupled signal has a DC offset of 100 mV, measured by the mean measurement parameters P2. The AC-coupled signal has the same peak-to-peak amplitude (P5) but a mean(P6) of near-zero V. The AC-coupled signal’s RMS amplitude (P3) reads 167.5 V because it includes the RMS value of the DC offset. The RMS value of the AC-coupled signal (P7) reads 134.4 mV because the mean value is zero. The DC-coupled signal’s standard deviation (sdev) (P4) is identical to the RMS values of the AC-coupled signal. Since the standard deviation calculation subtracts the mean value of the signal from the instantaneous value before computing RMS, the standard deviation is sometimes referred to as the AC RMS value.

Trigger input termination and coupling

The trigger input is another oscilloscope input that must be considered as it affects the instrument’s triggering. It is derived from one of the input channels, the external trigger input, or the power line. The trigger coupling for any of the inputs other than line is one of four possibilities: AC, DC, low-frequency reject (LF REJ), or high-frequency reject (HF REJ) (Figure 5).

Figure 5 The trigger input coupling selections include two bandwidth-limited modes (LF and HF REJ) and AC- and DC-coupling. Source: Art Pini

The AC and DC coupling perform as the AC and DC input coupling selections. LF REJ is an AC coupling mode with a high-pass filter in series with the trigger input. HF REJ is DC coupled with a low-pass filter in series with the trigger input. The cutoff frequencies of high-pass and low-pass filters are usually about 50 kHz. The LF and HF REJ coupling modes are usually used for noisy trigger signals, which might be encountered when testing switched-mode power supplies.

If the trigger input source is one of the input channels, then the trigger input inherits the termination impedance of the input channel. If the external trigger input is used, the input impedance can be selected (Figure 6).

Figure 6 The termination of the external trigger input includes both 50-Ω and 1-MΩ DC, along with a 1:1 and a 10:1 attenuator. Source: Art Pini

The termination is either 50 Ω or 1 MΩ. The external trigger is DC-coupled from the physical input to termination. The trigger coupling selection sets the coupling between the termination and the trigger.

Selecting input terminations when using a probe

Most modern oscilloscopes have intelligent probe interfaces that sense the probe’s presence and read its characteristics. The instrument adjusts the input termination and attenuation to match the probe’s requirements. For classical passive probes, simpler probe interfaces sense the probe’s sense pin to detect its presence and attenuation and set the instrument coupling and attenuation to match the probe. If the passive probe lacks a sense pin or an intelligent interface, then the attenuation setting of the input channel must be done manually.

50-Ω termination workarounds

The 50-Ω termination offers the highest bandwidth and is used with signal sources connected via 50-Ω coaxial cables or active probes that expect a 50-Ω termination. Serial in-line attenuations can be used to increase the voltage range of the 50-Ω input. AC coupling of the 50-Ω input can be accomplished using an external blocking capacitor. The lower frequency cutoff will be a function of the block’s capacitance.

Other traditional terminating impedances can be adapted to the 50-Ω termination by using an external in-line impedance pad. This is particularly common in applications such as video, where 75-Ω terminations are the standard. If an impedance pad is used, the pad’s attenuation has to be manually entered into the input channel setup.

1-MΩ termination workarounds

The 1-MΩ termination provides a high input impedance, which reduces circuit loading. It offers the highest voltage and offset ranges, but its bandwidth is restricted to 500 MHz or less. Care should be exercised when using it to measure low-impedance sources with frequencies greater than 40 to 50 MHz to avoid reflections, which will manifest themselves as ringing (Figure 7).

Figure 7 Measuring a low-impedance source using a 1-MΩ input can result in reflections that look like ringing (upper trace). Using a 50-Ω termination (lower trace) does not show the problem. Source: Art Pini

If you must use a 1-MΩ input, reflections can be reduced by soldering a 50-Ω resistor to the low-impedance source and connecting the 1-MΩ input to the resistor. This will help reduce reflections from the high-impedance termination back to the source.

The rail probe is the best of all possible worlds

Given that a typical application of oscilloscopes is measuring power supply ripple, the DC-coupled input’s limited offset voltages and the AC-coupled inputs’ attenuation call for a unique solution. The rail probe is a solution to measuring ripple on power rails that offers a large built-in offset, low attenuation, and high DC input impedance. The rail probe’s built-in offset and low attenuation permit the rail voltage to be offset in the oscilloscope by its mean DC voltage with high oscilloscope vertical sensitivity, achieving a noise-free view of small signal variations. The high DC input impedance eliminates the loading of the DC rail.

The input termination and coupling are important when setting up a measurement. Keep in mind how they can affect the signal acquisition and subsequent analysis.

Arthur Pini is a technical support specialist and electrical engineer with over 50 years of experience in electronics test and measurement.

Related Content

• Terminating a differential-input signal
• It’s not just 50 Ω: Some termination tips for differential and single-ended amplifiers
• Getting EMC design right – First time, Part 4: Terminations & Parts placement
• Digitizer front ends need the right inputs
• Build your own oscilloscope probes for power measurements (part 1)
• Basic oscilloscope operation
• Measure small impedances with Rogowski current probes

The post Oscilloscope input coupling: Which input termination should be used? appeared first on EDN.

There are numerous evergreen chips in the semiconductor industry, and this blog provides a sneak peek at some of these timeless technology marvels. Take µPC1237, for instance, NEC’s bipolar analog IC, which is still used in stereo audio power amplifiers and loudspeakers. Then, there is Toshiba’s fabled TA7317P, another classic IC used for power amplifier protection. The blog highlights the inner workings of these awesome chips and expands on why they are still in play.

Read the full blog on EDN’s sister publication, Planet Analog.

Related Content

• Audio amplifier selection in hearable designs
• Reference board exemplifies audio amplifier silicon
• Audio amplifier basics: Select the best topology for your design
• Audio amplifiers, class-T, class-W, class-I, class-TD and class-BS
• The NA1150 audio amplifier sets a new standard, driving speakers with PWM

The post A nostalgic technology parade of classic amplifiers appeared first on EDN.