Feed aggregator

Toggle, slide, push-pull, push-push, tactile, rotary, etc. The list of available switch styles goes on and on (and off?). Naturally, as mechanical complexity goes up, so (generally) does price. Hence simpler generally translates to cheaper. Figure 1 goes for economy by adding a D-type flip-flop and a few discretes to a minimal SPST momentary pushbutton to implement a classic push-on, push-off switch.

Figure 1 F1a regeneratively debounces S1 so F1b can flip ON and flop OFF reliably.

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

An (almost) universal truth about mechanical switches, unless they’re the (rare) mercury-wetted type, is contact bounce. When actuated, instead of just one circuit closure, you can expect several, usually separated by a millisecond or two. This is the reason for the RC network and other curious connections surrounding the F1a flip/flop.

When S1 is pushed and the circuit closed, a 10 ms charging cycle of C1 begins and continues until the 0/1 switching threshold of pin 4 is reached. When that happens, poor F1a is simultaneously set to 1 and reset to 0. This contradictory combination is a situation no “bistable” logic element should ever (theoretically) have to tolerate. So, does it self-destruct like standard sci-fi plots always paradoxically predict? 

Actually, the 4013-datasheet truth table tells us that nothing so dramatic (and unproductive) is to be expected. According to that, when connected this way, F1a simply acts as a non-inverting buffer with pin 2 following the state of pin 4, snapping high when pin 4 rises above its threshold, and popping low when it descends below. Positive feedback through C1 sharpens the transition while ensuring that F1a will ignore the inevitable S1 bounce. Meanwhile the resulting clean transition delivered to F1b’s pin 11 clock pin causes it to reliably toggle, flipping ON if it was OFF and flopping OFF if it was ON where it remains until S1 is next released and then pushed again.

Thus, the promised push-ON/push-OFF functionality is delivered!

The impedance of F1b’s pin 13 is supply-voltage dependent, ranging from 500 Ω at 5 V to 200 Ω at 15 V. If the current demand of the connected load is low enough, then power can be taken directly from F1b pin 13 and the Q1 MOSFET is unnecessary. Otherwise, it is, and a suitably capable transistor should be chosen. For example, the DMP3099L shown has an Ron less than 0.1 Ω and can pass 3 A.

But what about that “no switch at all” thing?

The 4013 input current is typically only 10 pA. Therefore, as illustrated in Figure 2, a simple DC touchplate comprising a small circuit board meander can provide adequate drive and allow S1 to be dispensed with altogether. It’s hard to get much cheaper than that.

Figure 2 An increase in RC network resistances allows substitution for S1 with a simple touchplate.

 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

• Setup and Hold Time Basics
• Use an op amp as a set/reset flip-flop
• New VFC uses flip-flops as high speed, precision analog switches
• CMOS flip-flop used “off label” implements precision capacitance sensor

The post Flip ON flop OFF appeared first on EDN.

Design engineers aiming to protect the input and output of op amps have several options. They can use an electrostatic discharge (ESD) diode or input current-limiting resistor alongside a transient voltage suppressor (TVS) diode. However, both design approaches have limitations. Here is why an op amp with integrated JFET input protection has better design merits.

Read the full article at EDN’s sister publication, Planet Analog.

Related Content

• Op amps: the 10,000-foot view
• Op-Amp Measurements Explained
• New op amps address new—and old—design challenges
• Are you violating your op amp’s input-common-mode range?
• Op Amp Circuitry Ultra-High-Precision Resistor Usage: Matching and Stability Importance

The post Build ESD protection using JFETs in op amps appeared first on EDN.

submitted by /u/Exploring-new [link] [comments]

Процес очищення стічних вод в університеті kpi ср, 02/05/2025 - 13:53

Intelligent power and sensing technology firm onsemi of Scottsdale, AZ, USA says that the Science Based Targets initiative (SBTi) has approved its near-term science-based emissions reduction targets. Validation of these targets attests that the planned decrease of onsemi’s greenhouse gas (GHG) emissions is aligned to the ambition of limiting global temperature rise to 1.5°C...

APC Electronics (APC-E) of Bend, OR, USA — which researches, develops and manufactures wide-bandgap power semiconductor products — has announced Luminus Devices Inc of Sunnyvale, CA, USA — which designs and makes LEDs and solid-state technology (SST) light sources for illumination markets — as its exclusive worldwide sales channel and go-to-market partner...

Штатний розпис на 2025 рік kpi вт, 02/04/2025 - 16:15

Peltz oscillator with injection locking

Oscillator injection locking is an interesting subject; however, it seems to be a forgotten circuit concept that can be beneficial in some applications.

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

This design idea shows an application of the built-in Bode capability within many modern low-cost DSOs such as the Siglent SDS814X HD using the Peltz oscillator as a candidate for investigating injection locking [1], [2], [3].

Figure 1 illustrates the instrument setup and device under test (DUT) oscillator schematic with Q1 and Q2 as 2N3904s, L ~ 470 µH, C ~ 10 nF, Rb = 10K, Ri = 100K and Vbias = -1 VDC. This arrangement and component values produce a free running oscillator frequency of ~75.5 kHz

Figure 1 Mike Wyatt’s notes on producing a Peltz oscillator and injector locking setup where the arrangement and component values produce a free running oscillator frequency of ~75.5 kHz.

Analysis and measurements

As shown in Figure 2, the analysis from Razavi [2] shows the injection locking range (± Δfo) around the free running oscillator frequency fo. Note the locking range is proportional to the injected current Ii. The component values shown reflect actual measurements from an LCR meter.

Figure 2 Mike Wyatt’s notes on the injection-locked Peltz oscillator showing the injection locking range around the free running oscillator frequency fo.

This analysis predicts a total injecting locking range of 2*Δfo, or 2.7 kHz, which agrees well with the measured response as shown in Figure 3.

Figure 3 The measured response of the circuit shown in Figure 1 showing an injection locking range of roughly 2.7 kHz.

Increasing the injection signal increases the locking range to 3.7 kHz as predicted, and measurement shows 3.6 kHz as shown in the second plot in Figure 4.

Figure 4 The measured response of the circuit shown in Figure 1 where increasing the injection signal increases the locking range to 3.7 kHz.

Note the measured results show a phase reversal as compared to the illustration notes (Figure 2) and the Razavi [2] article. This was due to the author not defining the initial phase setup (180o reversed) in agreement with the article and completing the measurements before realizing such!!

Injection locking use case

Injection locking is an interesting subject with some uses even in today’s modern circuitry. For example, I recall an inexpensive arbitrary waveform generator (AWG) which had a relatively large frequency error due to the cheap internal crystal oscillator utilized and wanted the ability to use a 10 MHz GPS-disciplined signal source to improve the AWG waveform frequency accuracy. Instead of having to reconfigure the internal oscillator and butcher up the PCB, a simple series RC from a repurposed rear AWG BNC connector to the right circuit location solved the problem without a single cut to the PCB! The AWG would operate normally with the internal crystal oscillator reference unless an external reference signal was applied, then the oscillator would injection lock to the external reference. This was automatic without need for a switch or setting a firmware parameter, simple “old school” technique solving a present-day problem!

 Michael A Wyatt is a life member with IEEE and has continued to enjoy electronics ever since his childhood. Mike has a long career spanning Honeywell, Northrop Grumman, Insyte/ITT/Exelis/Harris, ViaSat and retiring (semi) with Wyatt Labs. During his career he accumulated 32 US Patents and in the past published a few EDN Articles including Best Idea of the Year in 1989.

References

1. “EEVblog Electronics Community Forum.” Injection Locked Peltz Oscillator with Bode Analysis, www.eevblog.com/forum/projects/injection-locked-peltz-oscillator-with-bode-analysis. 
2. B. Razavi, “A study of injection locking and pulling in oscillators,” in IEEE Journal of Solid-State Circuits, vol. 39, no. 9, pp. 1415-1424, Sept. 2004, doi: 10.1109/JSSC.2004.831608. 
3. Wyatt, Mike. “Simple 5-Component Oscillator Works below 0.8V.” EDN, 3 Feb. 2025, www.edn.com/simple-5-component-oscillator-works-below-0-8v/.

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• Simple 5-component oscillator works below 0.8V
• Injection-lock a Wien-bridge oscillator
• Ultra-low distortion oscillator, part 2: the real deal
• The Colpitts oscillator
• Clapp versus Colpitts

The post Investigating injection locking with DSO Bode function appeared first on EDN.

AlixLabs AB of Lund, Sweden — which was spun off from Lund University in 2019 and has developed the Atomic Layer Etching (ALE) Pitch Splitting technology (APS) — has entered into a research collaboration with Linköping University on gallium nitride (GaN) and indium nitride (InN) deposition and etch, strengthening not only their own respective expertise in RF and power electronics but also aligning with the Swedish semiconductor sector...

Cree LED Inc of Durham, NC, USA (a Penguin Solutions brand) has launched XLamp XP-L Photo Red S Line LEDs for horticulture lighting. Designed for next-generation luminaires, the new LEDs deliver what is claimed to be outstanding efficiency and durability...

Lumentum Holdings Inc of San Jose, CA, USA (which designs and makes optical and photonic products for cloud/AI, networking and industrial and consumer laser applications) has appointed Michael Hurlston as president & CEO and director, effective 7 February. He succeeds Alan Lowe, who has served as president & CEO since 2015 and will continue to serve on the board of directors and as an advisor...

Хакатон Smart House System kpi вт, 02/04/2025 - 14:03

India’s 3D printing industry has witnessed significant growth, driven by advancements in additive manufacturing technologies and a surge in demand across various sectors. Here are  ten leading 3D printing companies in India, each contributing uniquely to the nation’s technological landscape:

1. Imaginarium

Based in Mumbai, Imaginarium stands as India’s largest 3D printing and rapid prototyping company. Serving industries such as jewellery, automotive, and healthcare, they offer a comprehensive suite of services, including design validation, prototyping, and batch production. Their state-of-the-art infrastructure and technical expertise make them a preferred partner for businesses seeking innovative solutions.

2. Divide By Zero Technologies

Headquartered in Maharashtra, Divide By Zero Technologies is a prominent 3D printer manufacturer catering to small and medium enterprises. Their patented Advanced Fusion Plastic Modeling (AFPM) technology ensures high precision and reliability. Notable products include the Accucraft i250+ and Aion 500 MK2, which are utilized by industry giants like Samsung and Mahindra.

3. Altem Technologies

Operating from Bangalore, Altem Technologies provides cutting-edge 3D printing solutions using Dassault Systems’ 3D Experience Platform. Their offerings, such as ENOVIA, CATIA, and DELMIA, cater to diverse sectors including aerospace, defense, and medical. Recognized for innovation, they received the Frost & Sullivan 2017 Award for advancements in 3D printing.

4. think3D

Founded by BITS graduates, think3D is headquartered in Singapore with a significant presence in India. They offer a wide range of 3D printers, scanners, and filaments, serving clients like Microsoft, Shell, and the Indian Navy. Their customized training programs, especially for schools under the Atal Innovation Mission, highlight their commitment to education and innovation.

5. Novabeans

Established in 2014, Novabeans operates offices in Gurgaon, Delhi, and Paris. As authorized resellers of brands like Ultimaker and LeapFrog, they provide a range of 3D printing solutions. Their 3D Printing for Education Program underscores their dedication to integrating additive manufacturing into academic curricula.

6. JGroup Robotics

Specializing in Fused Deposition Modeling (FDM) technology, JGroup Robotics offers 3D printers, on-demand services, and printing materials. Their printers utilize thermoplastic filaments to create precise three-dimensional objects, catering to various industrial applications.

7. 3Ding

With branches in Chennai, Bangalore, Hyderabad, and Mumbai, 3Ding is one of India’s oldest 3D printing suppliers. They offer a diverse range of 3D printers, scanners, and printing materials from leading brands. Their services include 3D design, printing, and scanning, along with workshops and training programs to promote additive manufacturing.

8. Boson Machines

Based in Maharashtra, Boson Machines is a leading 3D printing manufacturer utilizing technologies like FDM, SLA, and SLS. They offer services such as part production, injection molding, and CNC machining, providing comprehensive solutions from design to production.

9. 3D Print World

Operating under the leadership of Ankit Murarka, Aman Kedia, and founder Alok Goenka, 3D Print World offers top-tier 3D printing services and supplies printers and raw materials across India. Their commitment to delivering quality outputs promptly has established them as a trusted partner in the additive manufacturing sector.

10. Accreate Additive Labs

Co-founded by Ravi Shankar and Ravi Seshadri, Accreate Additive Labs provides design innovation in 3D printing by combining functional expertise with technological prowess. They focus on creating globally relevant intellectual property through their advanced additive manufacturing solutions.

The post Top 10 3D Printing Companies in India appeared first on ELE Times.

While finetuning its products and manufacturing process roadmap, Intel has realized that there are no quick fixes. After a briefing from Intel co-CEOs Michelle Holthaus and David Zinsner on upcoming CPUs and a slowdown in the ramp of the 18A node, Alan Patterson caught up with industry analysts to take a closer look at Intel’s predicament. He spoke with them about delayed CPU launches, the lack of an AI story, and the fate of Intel Foundry.

Read the full story at EDN’s sister publication, EE Times.

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• Intel Years From Success in Foundry Business, Analysts Say

The post Intel comes down to earth after CPUs and foundry business review appeared first on EDN.

Battery-powered applications, which have become indispensable over the last decade, require a certain level of protection to ensure safe use. This safety is provided by the battery management system (BMS). The BMS monitors the battery and possible fault conditions, prevents any hazardous situation due to the battery or its surroundings, and ensures that there is an accurate estimation of the battery’s remaining capacity or the level of battery degradation.

The main structure of a BMS for a low- or medium-voltage battery is commonly made up of three ICs, as described below:

1. Battery monitor and protector: Also known as the analog front-end (AFE), the battery monitor and protector provides the first level of protection since it’s responsible for measuring the battery’s voltages, currents, and temperatures.
2. Microcontroller unit (MCU): The MCU, which processes the data coming from the battery monitor and protector, commonly incorporates a second level of protection, including monitoring thresholds.
3. Fuel gauge (FG): The fuel gauge is a separate IC that provides the state-of-charge (SOC), state-of-health (SOH) information and remaining runtime estimates, as well as other user-related battery parameters.

Figure 1 The BMS architecture displays the key three building blocks. Source: Monolithic Power Systems

Figure 1 shows the main structure of a complete BMS for low- or medium-voltage batteries. The fuel gauge can be a standalone IC, or it can be embedded in the MCU. The MCU is the central element of the BMS, taking information from both the AFE and fuel gauge and interfacing with the rest of the system.

While three main components constitute the BMS, using these components without any additional consideration is not enough to ensure that the system meets the safety level required by certain industries. This article will explain the role that functional safety plays in non-automotive battery management systems and how to achieve the required safety level.

Functional safety introduction

Functional safety is a branch of overall safety focused on reducing the risk produced by hazardous events due to a functional failure of an electric/electronic (E/E) system. The goal is to ensure that the residual risk is within an acceptable range.

In recent years, the increasing use of E/E systems in different fields such as automotive, machinery, medicine, industry, and aviation has been accompanied by a greater emphasis on functional safety. These changes have led to the development of different functional safety standards.

ISO 13849, titled “Safety of machinery – Safety related part of control systems”, is a functional safety standard focused on the safety-related parts of control systems (SRP/CS) in the machinery field. This is a field that includes a wide spectrum of applications, from generic industrial machinery to mopeds and e-bikes. ISO 13849 defines different safety levels as performance level (PL), which range from PLa (lower safety level) to PLe (higher safety level).

This safety standard defines an accurate process for risk evaluation and reduction. It proposes a simplified method to determine the achieved PL based on three parameters: category, mean time to dangerous failure (MTTFD), and average diagnostic coverage (DCAVG), which is calculated by averaging all the DC associated to the different safety measures applied in the system.

The category is a classification of an SRP/CS that describes its resistance to faults and the subsequent behavior in the event of a fault condition. There are 5 categories (B, 1, 2, 3, and 4).

Architecture has the biggest impact on the category. The basic architecture of an SRP/CS is composed of three functional blocks: an input, a logic block, and an output (Figure 2). Figure 2 corresponds with the architecture proposed for category B and category 1, and it’s called a “single-channel” architecture. A single-channel architecture is considered the most basic architecture to implement the nominal functionality of the SRP/CS, but it’s not intended for any diagnostic functionality.

Figure 2 The above architecture is proposed for category B and category 1. Source: Monolithic Power Systems

Category B and 1 rely on the reliability of their components (MTTFD) to ensure the integrity of the safety functions. If a component implementing the safety function has a failure, a safe state can no longer be guaranteed, as no diagnostics are implemented (DCAVG = 0).

For category 2, the proposed architecture is called “single-channel tested.” The base of this architecture is the same as the single-channel architecture, but with an added test equipment block that can diagnose whether the functional channel is working correctly. If a component implementing the safety function has a failure, the safety function is not carried out; however, a safe state can be achieved if the failure is diagnosed by the test equipment.

For category 3 and category 4, the proposed architecture is called “redundant channels,” which is implemented with two independent functional channels that can diagnose issues on the other channel. If a component implementing the safety function has a failure, the safety function can still be carried out by the other channel. Designers should select the SRP/CS category based on the targeted safety level of each safety function.

Achieving functional safety step-by-step

The ISO 13849 standard defines an iterative process during which the SRP/CS design is evaluated to determine the achieved PL and check whether that safety level is sufficient or must be improved in a new loop. The process includes three different methods for risk reduction: risk reduction via safe designs measures, risk reduction via safeguarding, and risk reduction via information for use. ISO 13849 supports risk reduction via safeguarding (Figure 3).

Figure 3 ISO 13849 supports risk reduction via safeguarding. Source: Monolithic Power Systems

The safeguarding process starts by defining the safety functions of the SRP/CS, in which the required performance level (PLr) is defined after the risk analysis is conducted. The PLr is the target PL of the SRP/CS for each safety function.

The next step includes designing the SRP/CS for the specified safety requirements. This entails considering the possible architecture, the safety measures to implement, and finalizing the design of the SRP/CS to perform the relevant safety functions.

Once the SRP/CS is designed, evaluate the achieved performance level for each safety function. This is the core step of the entire safeguarding process. To evaluate the achieved PL, define the category and then calculate the MTTFD and DCAVG of the SRP/CS for each individual safety function.

The MTTFD is calculated per channel, and it has three levels (Table 1).

Table 1 MTTFD, calculated per channel, has three levels. Source: Monolithic Power Systems

Table 2 shows the four levels for defining the DC of each diagnostic measure.

Table 2 There are four levels for defining the DC of each diagnostic measure. Source: Monolithic Power Systems

The achievable PL can be determined using the relevant parameters (Table 3).

Table 3 Relevant parameters help determine the achievable PL. Source: Monolithic Power Systems

The achievable PL can only be confirmed when the remaining requirements and analyses defined by the standard are implemented in the design. These requirements must comply with systematic failures management, common cause failure (CCF) analysis, safety principles and software development, if applicable.

Once this process is complete, the PL achieved by the SRP/CS for a concrete safety function should be verified against the PLr. If PL < PLr, then the SRP/CS should be redesigned, and the PL evaluation process must begin again. If PL ≥ PLr, then the SRP/CS has achieved the required safety level, and validation must be executed to ensure the correct behavior through testing. If there is an unexpected behavior, the SRP/CS should be redesigned. This process should be reiterated for each safety function.

Functional safety level according to each market

Battery-powered devices are used in countless markets, and each market demands different functional safety specifications according to how dangerous a failure could be for humans and/or the environment. Table 4 shows the functional safety level required by some of the main markets. Note that these levels are constantly changing and may be different depending on each engineering team’s design.

Table 4 This is how PL is determined based on market. Source: Monolithic Power Systems

Although these are the current performance level market expectations, electromobility and certain energy storage applications may move into PLd due to the constant issues in battery-powered devices around the world. For example, faulty energy storge applications have resulted in fires in U.S. energy storage system (ESS) facilities. In U.K., more than 190 persons have been injured, and eight persons have been killed by fires sparked by faulty e-bikes and e-scooters.

All these events could have been prevented by a more robust and reliable system. The constant need for increasing safety levels means it is vital to have a scalable solution that can be implemented across different performance levels.

A functional safety design proposal

Take the case of an ISO 13849-based BMS concept that Monolithic Power Systems (MPS) has developed by combining an MCU with its MP279x family of battery monitors and protectors. This system is oriented to achieve up to PLc safety level for a certain set of safety functions (SFs), as shown in Table 5. PLr determination is dependent on the risk analysis, in which small variations can take place, as well as the application in which the BMS is used.

Table 5 See the defined safety functions for the BMS concept. Source: Monolithic Power Systems

The solution proposed by MPS to achieve PLc can meet category 2 or category 3—depending on each safety function—as for certain safety functions. There is only a single input block and for others, there are redundant input blocks.

Figure 4 shows how to implement SF2 and SF4 to prevent the battery pack from over-charging and under-charging. In the implementation of the SRP/CS, there are two logic blocks: the battery monitor and protector (logic 1) and the MCU (logic 2). These logic blocks are used to diagnose correct functionality of different parts in the design.

Figure 4 Here is how to implement SF2 and SF4. Source: Monolithic Power Systems

The implementation of single or duplicated input is determined by the complexity and cost in each case. To ensure that the safety functions for a single input are compliant with PLc, additional safety measures can be taken to increase the diagnostic capability; an example is a cell voltage plausibility check to verify that the cell voltage measurements are correct.

Functional safety used to be relevant for automotive products, but nowadays most modern markets demand the manufacturer to comply with a functional safety standard. The best-known safety standard for non-automotive markets is ISO 13849, a system-level standard that ensures an application’s safety and robustness.

Miguel Angel Sanchez is applications engineer at Monolithic Power Systems.

Diego Quintana is functional safety engineer at Monolithic Power Systems.

Related Content

• The ins and outs of battery management system (BMS)
• Multi-Cell Front-End Increases Battery Lifetime and Safety
• How does battery management electronics enhance battery safety?
• Perform functional testing of battery management systems for hybrid electric vehicles
• High-Performance Electromobility Solutions with Battery Management and Embedded Technology

The post Functional safety in non-automotive BMS designs appeared first on EDN.

There are two built-in computers, one running windows 10 (visible on photo 8) and another one running (I think) custom firmware (little screen on top). There were 20 batteries total. You can see internal network switches there, amazing. We did an x ray of a drill to test it's functionality. Also as soon as we discovered it was running windows we had to open paint. We couldn't connect to internet due to security concerns, but it has 4 wireless antenas around it submitted by /u/antek_g_animations [link] [comments]

План наукових та науково-технічних заходів kpi пн, 02/03/2025 - 22:30

Remember my April 2023 teardown of Spotify’s now-defunct Car Thing?

Ditch the touchscreen LCD, broaden functionality and that’s Amazon’s Echo Auto in a nutshell:

Shown here and introduced in mid-2019 is the first-generation version of the product, which I’ll be tearing down today. It originally sold for $49.99 but was initially promo-priced at half that amount ($24.99), which is how it came to be in my possession that same summer. The second-gen successor, introduced three years (and three months) later with shipments beginning in mid-December 2022, was smaller, with beefier mounting options, equivalent claimed input-sound quality (in spite of fewer integrated mics) and a supposed superior sonic output, along with a permanent 24.99 price cut. It’s still available for purchase:

Considering that the first-gen Echo Auto has been sitting on my shelf for more than 5 years now awaiting my dissection attention, the beat-up condition of its packaging, as-usual accompanied by a 0.75″ (19.1 mm) diameter U.S. penny for size comparison purposes, would be understandable…except that it’s looked like this since it first showed up at my front door!

Rip off the retaining tape and flip open the top flap:

and the contents come into view.

Post-removal, here’s our patient, alongside the similarly clear plastic-clad (at least for the moment) dashboard mount:

the “cigarette lighter” 12V socket-based power supply, flanked by (on the left) a 3.5mm TRS extension cable and (on the right) the USB-A to micro-USB power cable, all three of which I’ll hold on to for future reuse:

and, of course, a few slivers of documentation:

Next, a couple of additional looks at the adhesive dash mount (and its accompanying preparatory dashboard-cleaning handi wipe), now free of its clear plastic sarcophagus:

and the power adapter, with a handy included second USB-A jack, and decent aggregate output:

With the contents removed and its insides now ostensibly empty, the box still seems hefty, but I confirmed that there was nothing left within. Must be all those folded cardboard layers:

And now for some initial perspectives on our patient, with dimensions of 3.3” x 1.9” x 0.5” (85 mm x 47 mm x 13.28 mm) and a weight of 1.6 oz (45 grams). Front:

The left “mute” button, by the way, turns red when active, as with other Echo devices, as does the more general multicolor device-status light bar along the bottom edge:

The device top is comparatively bland, although there is that inside access-tempting seam:

The sides are more interesting. Along the right are the 3.5mm auxiliary analog audio output and the micro-USB power connector. The former was a key motivation for me to initially buy the Echo Auto, as none of my vehicles have integrated Bluetooth, far from Apple’s CarPlay or Google’s Android Auto services—only my wife’s newer car does—but their sound systems all have AUX inputs.

And on the left? No, that’s not a SD card slot. Believe it or not, it’s the aperture for the integrated speaker, pointing toward the vehicle’s driver (at least sometimes):

Finally, the device backside, revealing (among other things) the FCC ID (2ALV8-4833) and magnetic dash mount inset (I trust there’s metal inside, on the other side of the chassis):

Speaking of “inside”, let’s get to it. A preparatory peek underneath one of the rubber feet seemingly wasn’t promising:

So, I turned my attention to the aforementioned top side seam. The first “spudger” I tried slipped inside fairly easily but was too flimsy to make any separation headway:

Its beefier Jimmy sibling, however, was no more successful:

On a hunch, I revisited those feet. That grey piece of plastic you saw underneath the one in the earlier photo? Turns out, it pops out too:

And underneath each of the plastic pieces is a hex screw head begging for attention:

That’s more like it:

FWIW, as it turns out from my subsequent research, I wasn’t the only one initially flummoxed!

There’s that piece of metal I’d previously forecasted would be on the other side of the dashboard mount inset. Below it, along the bottom edge, is a portion of the light guide assembly (presumably associated with a to-be-seen row of LEDs on the PCB):

And here’s our first glimpse of the system’s guts:

On the left (right when viewed from the front; remember that we’ve so far removed the back panel) is the micro-USB power input, with the 3.5 mm audio jack above it. Along the bottom are—I told you so—a row of 11 multicolor LEDs. At the top is the PCB-embedded Bluetooth antenna. And on the right? That, believe it or not, is the mono speaker! Let’s get it outta there:

Lest there be any doubt as to its magnet-inclusive acoustic identity:

And now for some closeups, with perspectives oriented per the transducer as originally installed in the previous photo. Right side, where the sound comes out; I seriously doubt it “goes to 11”:

Front:

Left side:

Back, exposing the speaker’s electrical contacts:

And finally, the top:

and bottom:

With the speaker removed, you can now see the PCB-resident “spring” contacts that mate up with those on the speaker. Note, too, that the PCB holes corresponding to mounting pins on the speaker backside are foam-reinforced, presumably to suppress vibration while in operation:

And now let’s get the PCB out of there, a thankfully easier process than what’d previously been necessary to get our first glimpse of it, as it now lifts right out of the remaining chassis half:

The stuck-on RFID tag inside the front chassis half is an interesting story in and of itself. As this blogger also postulates (in addition to identifying the source—Inpinj—of the IC connected to the comparatively massive antenna), I believe that it finds use in uniquely associating the device with your Amazon account prior to its shipment to you. To wit, I happened to notice, in reviewing my Amazon order history to refresh my memory of when I bought the Echo Auto and what I paid for it, that the device serial number was also included in the relevant transaction listing. And at the bottom is the other portion of the light guide assembly:

Here’s the already-seen PCB backside, now free of its previous plastic chassis surroundings:

And here’s the first-time glimpsed PCB front side:

Let’s first get rid of that rubber gasket, which thankfully peeled off easily:

Note the LEDs straddling the left-side switch, which generate the red “mute” indication. Note, too, eight total circular apertures for the microphone array, one in each corner of each of the two switches. And as for the ICs between the switches, let’s zoom in:

Unfortunately, I had no luck in identifying any of these; I’m once again hopeful that insightful readers can fill in the missing pieces. The one at the bottom (U10), when correctly oriented (it’s upside-down marked in the photo) has what looks to be an “OXZ” company logo stamped in the upper left corner. The three-line product marking next to it looks like this:

L16A
0225
ZSD838A

I found similar markings (albeit with second-line deviations) on an IC inside a 2018-2019 13” Apple MacBook Air, within a Facebook post which I stumbled across thanks to Google Image Search, but that’s all I’ve got. Above it are two ICs (U2 and U6) identically marked as follows:

YE08
89T

which may be 8-bit bidirectional voltage-level translators, specifically Texas Instruments’ TXB0108. And in U10’s upper right corner is another (U9) with the following two-line marking:

T3182
3236A

Again…

Let’s flip the PCB back over to its backside and see if we have any better luck. Step one is to get those two Faraday Cages’ tops off:

That’s better:

The IC at far left (U20), next to a wire-wound inductor whose guts seem to have been inadvertently exposed by the spudger while removing the cage, is labeled thusly (and faintly so):

25940A
TI 89I
AE24

“TI” stands for “Texas Instruments”, I’m pretty confident, reflective of the longstanding partnership between that supplier and Amazon also noted in several of my past Echo product dissections. And Texas Instruments does have a “25940” in its product line, specifically the TPS25940, the “eFuse Power Switch”, a “compact, feature-rich power management device with a full suite of protection functions, including low power DevSleep support”. If that’s actually what this chip is, its proximity to the micro-USB power input therefore makes sense. But the product page also claims that the TPS25940 is intended for use in SSDs. Hmm…

Above and to the right of it is another chip with “TI” in the markings (U14), but the first line thankfully makes its function more obvious, at least as far as I’m guessing:

DAC
3203I
TI 88J
PL49

This, I believe, is Texas Instruments’ TLV320DAC3203 “stereo” audio DAC with a stereo 125-mW headphone driver and audio processing. Proximity is again part of the probable identity tip-off here, since it’s near the analog audio output. Plus, of course, there’s the first-line “DAC” mark…

Move further to the right and the next large(r) IC you encounter (U19), also seemingly chipped in one corner during my clumsy cages-removal surgery, has the following two-line primary markings (along with, above them, a combo mysterious swirl followed by a seeming QR code):

W902B108
SR3F2

Google searches on the markings proved fruitless but, based on some other research I’ve done on this system, I’m still going to take a guess. The Amazon product page indicates that in addition to the main system SoC (hold that thought), there’s also an “Intel Dual DSP with Inference Engine” inside. The relevant DeviWiki product page further clarifies that it’s an “Intel Quark S1000 Processor.” Indulge me in a brief history diversion: a bit more than a decade ago, Intel announced its Quark line of defeatured 32-bit x86 processors (even more so than its Atom CPUs) for wearables and other cost- and power-sensitive applications. The Quark family, which Intel obsoleted in 2019, also included at least one coprocessor, the S1000, which embedded two Cadence Tensilica LX6 DSP cores. Intended for speech recognition, I assume that the S1000 also handled echo cancellation, background noise suppression and other array mic functions in this particular design. And I’m also guessing that, although there’s no Intel logo mark, it’s this chip.

Now for the main system SoC (U23), which is to the right of the previous “mystery chip” and is thankfully more easily identifiable. It’s MediaTek’s MT7697, introduced in 2016 and described as a “highly integrated 1T1R 2.4GHz Wi-Fi/Bluetooth 4.2 application processor with an Arm Cortex-M4 and a power management unit”, MediaTek being another supplier with a longstanding Amazon relationship.

Which leads us to the last chip I’ll showcase, to its right, with a two-IC PCB identifier (U17/U18). At first, I thought the “MT” mark might also indicate MediaTek sourcing but, given that the MT7697 already also handles Bluetooth and power management functions, I couldn’t think of anything else this one could tackle. But then I remembered I hadn’t yet mentioned memory, either volatile or nonvolatile. This insight led me to suspect that “MT” probably instead stands for “Micron Technology” and that this is a stacked module containing both DRAM and flash memory (capacities and specific technology types and generations unknown).

In closing, I’ll (re)point out two other aspects of this side of the PCB; the eight MEMS microphones whose apertures you saw earlier on the other side, and the PCB-embedded top-edge Bluetooth antenna that I first noted when the PCB was still chassis-bound. And with that, having just passed through 2,000 words, I’ll wrap up with a reiteration of the invitation to assist me with any/all of the ICs I was unable to ID, and/or to share any other insights or other thoughts, in the comments. Thanks as always in advance!

—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.

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