Texas Instruments’ eFuse can be used for hot-swap and power rail protection applications
Texas Instruments’ TPS1663 is an easy-to-use, positive 60 V, 6 A eFuse with a 31 mΩ integrated FET. Protection for the load, source, and the eFuse itself are provided along with adjustable features such as accurate overcurrent protection, fast short circuit protection, output slew rate control, overvoltage protection (OVP), and undervoltage lockout (UVLO). The device includes adjustable overcurrent functionality. PGOOD can be used for enabling and disabling control of the downstream DC/DC converters.
The shutdown pin provides external control for enabling and disabling the internal FET and placing the device in a low current shutdown mode. For system status monitoring and downstream load control, the device provides fault and precise current monitor output. The MODE-pin allows flexibility to configure the device between the two current-limiting fault responses (latch-off and auto-retry). The devices are available in a 4 mm × 4 mm 24-pin VQFN package and are specified over a -40°C to +125°C temperature range.
Features
Operating voltage: 4.5 V to 60 V (absolute max: 67 V)
Integrated 60 V, 31 mΩ RON hot-swap FET
Adjustable current limit: 0.6 A to 6 A (±7%)
Low quiescent current: 21 µ in shutdown
Adjustable UVLO and OVP cut-off with ±2% accuracy
PGOOD
Package: VQFN
Adjustable output slew rate control for inrush current limiting:
Charges large and unknown capacitive loads through thermal regulation during device power-up
Selectable OVC fault response options between auto-retry and latch-off (MODE)
Texas Instruments’ 24-bit, 32 kSPS ADC is optimized for cost-sensitive applications that require simultaneous sampling
Texas Instruments’ ADS131M08 8-channel, simultaneously-sampling, 24-bit ΔΣ ADC offers wide dynamic range, low power, and energy-measurement-specific features. These features make the device ideal for energy metering, power metrology, and circuit breaker applications. The ADC inputs can be directly interfaced with a resistor-divider network or a power transformer to measure voltage or to a current transformer or a Rogowski coil to measure current.
The individual ADC channels can be independently configured depending on the sensor input. A low-noise programmable gain amplifier (PGA) provides gains ranging from 1 to 128 to amplify low-level signals. This device integrates channel-to-channel phase calibration and offset and gain calibration registers to help remove signal-chain errors.
Features
Eight simultaneously sampling differential inputs
Programmable data-rate up to 32 kSPS
Programmable gain up to 128
Noise performance:
Dynamic ranges: 102 dB (gain = 1, 4 kSPS), 80 dB (gain = 64, 4 kSPS)
High-impedance inputs for direct sensor connection:
Input impedance for gains of 1, 2, and 4 (330 kΩ), 8, 16, 32, and 64 (1 MΩ)
Low power consumption: 6.0 mW at 3 V AVDD and DVDD
Package: 32-pin TQFP or 32-pin WQFN
Operating temperature range: -40°C to +125°C
Applications
Electricity meters: commercial and residential
Circuit breakers
Battery test equipment
Battery management systems
A low-drift 1.2 V reference is integrated into the device reducing printed circuit board (PCB) area. Cyclic redundancy check (CRC) options can be individually enabled on the data input, data output, and register map to ensure communication integrity. The complete analog front-end (AFE) is offered in a 32-pin TQFP or leadless 32-pin WQFN package and is specified over the industrial temperature range of -40°C to +125°C.
IBASE Technology, a manufacturer of application-specific embedded computer platforms, has announced the release of the RM-N8MMI SMARC 2.0 CPU Module built with NXP ARM Cortex-A53 i.MX 8M Mini Quad 1.6GHz industrial-grade processors. Together with a customised carrier board equipped with an array of serial, video and network interfaces, the RM-N8MMI solution is the perfect choice for multimedia and IoT applications that require low power and high performance in transportation passenger information and entertainment systems.
“The modular approach of the SMARC specification allows customers to take full advantage of the scalability benefit, optimized time-to-market and upgrade capability,” said Archer Chien, Director of Solution Product Planning Dept. at IBASE. “The cost-efficient RM-N8MMI offers a competitive advantage to our customers by reducing the Total Cost of Ownership (TCO) and lowering the lifecycle costs.”
The new RM-N8MMI module measures 82mm by 50mm and features Vivante’s GC 320 GPU, 2GB soldered LPDDR4 and up to 64GB eMMC flash memory. Extensive I/Os supported include 1x GbE, 2x USB 2.0 with OTG interface, 1x MIPI CSI-2 for image capture, 4x UART, 2x SPI, 2x I²S, 2x SPI and 1x PCI-E (x1) Gen2.
Shipped with extended longevity of up to 10 years, the RM-N8MMI is provided with Yocto BSP and Android 9.0 support. It is available with an industrial-grade variant that runs from -40°C to +85°C extended temperature, as well as the RP-103-SMC carrier board providing users a rich set of interfaces and 12V~24V DC input.
For more information regarding available options and configurations, please visit www.ibase-europe.com
The EVLSTCH03-45WPD 45W USB Type-C® Power Delivery 3.0 adapter from STMicroelectronics is a USB-IF certified solution and reference design. The EVLSTCH03-45WPD is an isolated ac-dc power supply with a standalone USB PD controller. The board implements at the primary side a quasi-resonant flyback converter based on the STCH03 controller with optocoupler feedback for voltage regulation. This controller combines a high-performance low-voltage PWM controller chip with a 650V HV start-up cell in the same package. The STCH03 controller drives the gate of the new 650V MDmesh™ M6 technology Power MOSFET STD7N65M6.
At the secondary side, to increase the system efficiency, the rectification is based on the SRK1001 adaptive synchronous rectification controller. This controller drives the gate of the 100V STripFET™ F7 technology Power MOSFET STL110N10F7.
Always on the secondary side the CC/CV regulation loop to drive the power regulation stage and the USB Type-C® PD interface are based on the STUSB4761 controller. This controller offers the benefits of a full hardware USB PD stack allowing robust, deterministic and safe negotiation in line with USB PD standard.
The EVLSTCH03-45WPD is protected against destructive electrostatic discharge from the USB Type-C® connector using a Dual Transil array for ESD protection ESDA25L.
Key Features
USB-IF certified
USB Type-C® PD 3.0 references:
Power Brick EVLSTCH03-45WPD TID: 2071
PD Controller STUSB4761 TID: 2070
Universal ac input range VIN:
90- to 264-Vac
PD output profile:
5V – 9V – 12V – 15V @ 3A
20V @ 2.25A
Maximum efficiency at full load:
90% @ ac input range
No-load consumption (no cable plug-in):
< 30mW @ 230Vac
Energy efficiency meeting all DOE and UE CoC requirements
Isolated quasi-resonant flyback topology with adaptive synchronous rectification
Programmable output voltage and current protections
Safety according to EN60065
EMI according to EN55022 – Class B
Compact form factor: 70 x 50 X 26.8 mm
RoHS compliant
The evaluation board implements a robust adapter protected for output overvoltage, output undervoltage, output overpower and output short-circuit. This reference design, based on STMicroelectronics semiconductors, helps designers to develop adapters with a short bill of materials in order to obtain a cost-effective and fast design.
The PicoScope 6000E series brings very high speed performance to an 8 analog channel, 16 digital channel oscilloscope with 5GSa/s sampling and 4GSa deep memory.
Saelig Company, Inc. has introduced the PicoScope 6000E Series 8-channel 500MHz Oscilloscopes, which provide 8 to 12 bits of vertical resolution, 5GSa/s sampling rate, and 4GSa memory, allowing these scopes to display single-shot pulses with 200ps time resolution. The two models in the 6000 series are the PicoScope 6804E with 8-bit A/D resolution and the PicoScope 6824E with 8, 10, or 12 bits “FlexRes” resolution. Both models can operate with an extra 4 bits of resolution with the enhanced vertical resolution software feature — a digital signal processing technique built into PicoScope 6. These oscilloscopes offer 8 analog channels, plus 8 or 16 optional digital channels when using the plug-in TA369 MSO pods, enabling accurate time-correlation of analog and digital channels.
Both 6000E models include a 14-bit 200MS/s arbitrary waveform generator (AWG). Its variable sample clock avoids the jitter on waveform edges seen with fixed-clock generators and allows the generation of accurate frequencies down to 100μHz. AWG waveforms can be created or edited using the built-in editor, imported from oscilloscope traces, loaded from a spreadsheet or exported to a .csv file. The SuperSpeed USB 3.0 interface and hardware acceleration ensure that the display is smooth and responsive even with long captures. PicoScope 6 software includes decoders for many serial protocols.
With up to a million points, PicoScope’s FFT spectrum display has excellent frequency resolution and a low noise floor. A click of a button will display a spectrum plot of the active channels, with a maximum frequency of up to 500MHz. Using a 4K monitor attached to the controlling PC, PicoScope 6 software can display more than ten times the information of ordinary oscilloscopes. PicoScope software also supports dual monitors, allowing instrument control and waveforms displayed on one, and large data sets from serial protocol decoders or DeepMeasure results on the second monitor.
An optional Pico Oscilloscope Probe Positioning System holds a circuit board firmly, as well as positioning probes hands-free for up to eight probes simultaneously. Probes with compression tips make contact with points of interest on a PCB and remain in contact while measurements are taken with PicoScope software.
The 6000E’s 8 analog channels have the timing and amplitude resolution needed to reveal signal integrity challenges such as glitches, runts, dropouts, noise, distortion and ringing. This Series gives the waveform memory, resolution and analysis tools needed to test today’s high‑performance embedded computers and next-generation embedded system designs. The 6000E oscilloscopes are ideal for design engineers working with signal processing, power electronics, mechatronics, and automotive designs, and for researchers and scientists working on multi-channel high-performance experiments in physics labs, particle accelerators, and similar facilities. Supported by the PicoScope 6 software, these devices offer an ideal, cost-effective package for design, research, test, education, service, and repair.
Made by Pico Technology, Europe’s award-winning test and measurement manufacturer, the PicoScope 6000E oscilloscopes are available now from Saelig Company, Inc. their USA technical distributor.
Since the internet remains quite vulnerable to security breaches, new measures have been taken to ensure that users are able to safely interact and navigate it in no time. Earlier last year, a new security model called the FIDO2 WebAuthn (Web Authentication) that helps to eliminate all forms of password theft and replay attacks was developed by the big tech companies and accepted for recommendation by the W3C Consortium. The FIDO2 WebAuthNtechnology which has much higher security than passwords was built to help users log in to their online accounts with their mobile phone, biometrics or FIDO security keys instead of having to always remember the many passwords that they have used for different sites.
Taking it further, Electrical Engineer Andrew Ovcharov, last summer started working on developing his own FIDO2 Authenticator, the “URU Auth” derived from the abbreviation “You Are You”.
The URU key, about the size of a small flash drive, is a custom standalone wireless biometric FIDO2 WebAuthN Authenticator which uses a fingerprint scanner for authentication on WebAuthN-enabled websites. Instead of having to use mobile devices, users can power their URU key, scan a registered fingerprint and interact easily with WebAuthN web applications.
Ovcharov has been working on the URU key for about six months now and the project has successfully gone through the major developmental stages.
”…I have built a prototype board for the authenticator device, the fingerprint scanner was connected and the fingerprint image was acquired. The security chip was connected and communicated. Now all the small pieces work together as one device and the device starts to get a shape. I can hold it in my hand, I can confirm the authentication request and it makes me absolutely happy how it goes”, says the engineer.
The URU key, for now, features an ESP32 Pico D4 microcontroller for the wireless transfer of data, the GROW R300 fingerprint scanner for registering fingerprints, a few LEDs, connectors for programming and user feedback, and the ATECC508a security chip which implements the FIDO2 WebAuthN.
Ovcharov is putting more work into the project as he is currently experimenting on power options to make the device really autonomous while keeping it lightweight and pretty small.
The project’s progress is being documented beautifully on Ocharov’s website. You can follow the page to learn more about the device.
Peak Electronic Design Ltd has designed a 3D stand for their popular Peak Atlas Instruments. The stand makes the instrument sit on an angle (30°) view on top of your bench for easy reading and handing. This has been designed by Jez Siddons of Peak Electronic Design Ltd , directly using the CAD data for the Peak Atlas enclosure, so it fits like a glove and is easy to fit or remove. It also has sprung beams that allow for easy fitting. The company was kind enough to release the design so you can print your own stand. So, you can either purchase a printed stand for £9.00 or print your own by downloading the design files.
This is supplied in two parts with screws for your assembly. Price is preliminary and subject to change, as Peak says and if you purchase it, it will be printed in PLA or PETG and an unspecified color.
After its successful entry into the 3.5-inch SBC market in the middle of last year, congatec is now introducing a new carrier board in this standardized footprint, which impresses with a socket for Arm based SMARC modules. Its I/Os are optimized for use with congatec’s entire NXP i.MX8 module portfolio and it comes in 12 different processor configurations. Considering that the ARM processor world is traditionally characterized by proprietary designs, this 3.5-inch board design is a step further towards commercial-off-the-shelf (COTS) available standard boards and systems, offering fastest time to market. OEMs can implement them in their system solutions without any hardware development effort, using the large ecosystems of standard form factors. Rapid customization of I/Os is another benefit of such a modular design and most suitable for any small or medium sized project.
“Our new modular 3.5-inch carrier board makes Arm designs also increasingly attractive for small industrial lot sizes, which until now have been dominated by x86 technology due to a lack of suitable ARM products. And since customer-specific designs can be implemented faster and more cost-effectively with modular boards, this COTS platform is also an ideal basis for custom designs of NXP i.MX8-based systems,” said Martin Danzer, Director Product Management at congatec.
The new conga-SMC1 3.5-inch board not only features a SMARC socket for scalable processor performance, but is also optimized for MIPI cameras, which can now be connected directly and without any additional hardware. Thanks to two MIPI-CSI 2.0 connectors, it is even possible to develop systems that provide three-dimensional vision and can therefore also be used for situational awareness in autonomous vehicles. Combined with processor-integrated support for artificial intelligence and neural networks, this COTS platform offers everything developers need for smart vision systems. Comprehensive software support with precompiled binaries completes the new COTS offering.
congatec expands 3.5-inch offering to NXP i.MX8 processors
The feature set in detail
The new conga-SMC1 3.5-inch board is scalable in 12 performance steps from the most powerful i.MX 8QuadMax processors to the i.MX 8M Mini processors in 14 nm technology and the low-power i.MX 8X processors. On a footprint measuring just 146×102 mm, the conga‑SMC1 offers dual GbE, 5x USB and USB hub support as well as SATA 3 for external hard drives or SSDs. For specific expansions, the board offers a miniPCIe slot as well as an M.2 Type E E2230 slot with I2S, PCIe and USB, and an M.2 Type B B2242/2280 with 2x PCIe and 1x USB. An integrated MicroSim slot for IoT connection is also provided, next to specific embedded interfaces such as 4x UART, 2x CAN, 8x GPIO, I2C and SPI. Displays can be connected via HDMI, LVDS/eDP/DP and MIPI-DSI. The board further offers two MIPI-CSI inputs for camera connection. I2S sound can be implemented via audio jack. As they come with SMARC sockets, the new 3.5-inch conga-SMC1 can be equipped extremely flexibly with any of the 12 new NXP i.MX 8 based modules. In terms of software, congatec offers precompiled binaries with a suitably configured bootloader, appropriately compiled Linux, Yocto and Android images, as well as all required drivers that are available to congatec customers on GitHub.
The series behavior of the three elementary components of electronics has been detailed in our previous article Series RLC Circuit Analysis. In this tutorial, another association known as the parallel RLC circuit is presented.
In the first section, we present the elementary parallel RLC circuit and focus on its impedance.
The second section focuses on the AC behavior of the parallel RLC circuit. We highlight and explain the phenomenon of the resonance due to a parallel L//C configuration that explains some properties of parallel RLC circuits.
To conclude these two articles about RLC circuits, alternative configurations are presented in the last section.
Presentation
The parallel RLC circuit consists of a resistor, capacitor, and inductor which share the same voltage at their terminals:
fig 1: Illustration of the parallel RLC circuit
Since the voltage remains unchanged, the input and output for a parallel configuration are instead considered to be the current.
For a parallel configuration, the inverse of the total impedance (ZRLC) is the sum of the inverse impedances of each component: 1/ZRLC=1/ZR+1/ZL+1/ZC. In other terms, the total admittance of the circuit is the sum of the admittances of each component.
This total admittance satisfies:
The total impedance is therefore given by Equation 1 after taking the norm of the admittance:
eq 1: Total impedance of the parallel RLC circuit
From Equation 1, it is clear that the impedance peaks for a certain value of ω when 1/Lω-Cω=0. This pulsation is called the resonance pulsation ω0 (or resonance frequency f0=ω0/2π) and is given by ω0=1/√(LC).
AC behavior
Fast analysis of the impedance can reveal the behavior of the parallel RLC circuit. Consider indeed the following values for the components of the parallel RLC circuit: R=56 kΩ, L=3 mH, and C=5 nF.
From these values, we can compute the resonance frequency of the system ω0=2.6×105 rad/s. The circuit is supplied by an AC source which amplitude is 5 A and frequency varies from DC to 4×105 rad/S.
Figure 2 is a plot of the total impedance and output current as a function of the angular pulsation ω supplied to the circuit:
fig 2: Total impedance and output current of the parallel RLC circuit
It is clearly evidenced by this figure that around the resonance frequency, the impedance of the circuit peaks, which leads to a decrease of the current output around this same frequency.
Let’s focus on what happens in the circuit and more precisely between the capacitor and inductor in order to understand this behavior. Consider, therefore, to begin with, an L//C configuration in which the capacitor is initially charged. The following Figure shows the steps involved in a cycle called resonance:
fig 3: Cycle of resonance of an L//C circuit
Many things must be commented in Figure 3. First of all, the red and green arrows represent respectively the electric field across the capacitor and the magnetic field across the inductor. The arrows indicate the direction of the fields, a fully charged component is represented with many arrows while a discharged component has none.
The numbers represent the steps of the cycle, the next step after number 8 is step number 1. As highlighted in this series of figures, the resonance phenomenon is due to mutual charges and discharges occurring between the capacitor and the inductor. The speed at which this cycle evolves is given by the resonance frequency f0=1/(2π√(LC)).
In real circuits, this cycle is of course not perpetual as internal resistors dissipate energy by Joule’s heating. However, an AC source can force the circuit to maintain this exchange of current between the inductor and capacitor.
Specifically, when ωsource=ω0, the exchange of energy is maximum and all the current is flowing in between these two components and none in the mainline across a resistance (see Figure 4). Another way to understand that is through the concept of reactance. We remind that the reactances of a capacitor (XC) and an inductor (XL) are given by:
eq 2: Capacitor and inductor reactances
From the definition of ω0, it comes that XC(ω0)=XL(ω0). The currents across the components are therefore equaled but of opposite directions due to the phase-shifts of +90° in the inductor and –90° in the capacitor leading to a phase difference of 180°. This phenomenon can be seen in steps 2 and 4 or steps 6 and 8 in Figure 3.
When working around ω0, this configuration is commonly known as a rejector circuit. We detail this more in the following section where we show that an L//C circuit can be connected in series with a resistor to create a band-stop filter.
Alternative configurations
Band-stop filter
One possible interesting configuration that mixes both a parallel and series design is a parallel LC filter in series with an output load, we will call this circuit (L//C)-R in the following. A representation of this architecture is given in Figure 4 below:
fig 4: Illustration of the (L//C)-R circuit
If we call ZL//C the impedance of the parallel LC configuration, we can write that Vin=Vout+ZL//C×I. Knowing that I=Vout/R and by factorizing the expression by Vout, we can write after a few steps the transfer function of the (L//C)-R circuit:
eq 2: (L//C)-R transfer function
We consider L=3 mH, C=5 nF, and R=10 kΩ and 20 kΩ. It becomes clear after plotting this transfer function that the (L//C)-R circuit act as a band-stop filter around the same frequency ω0 as for the elementary parallel RLC circuit:
fig 5: Plot of the (L//C)-R transfer function
Figure 5 also highlights the fact that the bandwidth Δω of this band-stop filter becomes narrower when the resistance increases, which is in contradiction with the definition of the quality factor given in the series RLC article Qseries=(1/R)√(L/C)=ω0/Δω.
In fact, this definition is not valid for parallel circuits, the formula for a parallel configuration becomes Qparallel=1/Qseries=R√(C/L), which explains the behavior in Figure 4 previously pinpointed.
The characteristic parameters of the parallel RLC circuit are, as a matter of fact, the reciprocals to the series RLC circuit.
Band-pass filter
An interesting concept called duality enables us to directly find the behavior of a new circuit from the knowledge of another. It is deduced from the fact that the equations applying to the current or voltage to a certain configuration can be applied to the dual quantity of the dual configuration.
Let’s be a little clearer and consider again the band-stop filter example detailed above. We call this configuration (L//C)-R since a parallel (//) LC circuit is in series (-) with a resistance R. We have seen that this circuit act as a band-stop filter for the voltage.
The dual of this circuit is a (L//R)//R circuit illustrated in Figure 6:
fig 6: Dual circuit of Figure 5
The duality concept tells us that this dual circuit acts as the dual of a band-stop filter, which is a band-pass filter. To verify this affirmation, we can start by writing that Iin=Iout+YL//C×Vout which is the same equation shown in the previous section but applied for the current, as stated by the duality concept. YL//C is the admittance of the configuration L//C and equals 1/ZL//C.
Knowing that Vout=R×Iout and by factorizing the expression with Iout, it comes:
eq 3: (L//C)//R transfer function
We can see that Equation 3 is very similar to Equation 2 but the imaginary term is inversed which leads to the band-pass filter behavior. We can consider again the same values L=3 mH, C=5 nF, and R=10 kΩ and 20 kΩ and plot this transfer function in order to conclude this section and confirm about the band-pass filter:
fig 7: Plot of the (L//C)//R transfer function
Conclusion
The behavior of a parallel RLC circuit is quite different than the series configuration. This is due to the phenomenon of reciprocal exchange of energy of the L//C circuit called resonance.
This phenomenon is due to the mutual discharges/charges occurring between an interconnected inductor and capacitor. The impedance of such a circuit theoretically tends to an infinite value at a particular pulsation ω0 called the resonance pulsation (or resonance frequency for f0). In real circuits, this impedance peaks due to internal resistive behaviors.
We have seen in the last section, that integrated in series with an output load, a band-stop filter can be made. Connected in parallel, however, leads to the opposite filter: a band-pass filter.
All the prototyping tools you need in Geppetto workspace on SEEED platform
Altium, announces that Seeed, the IoT hardware enabler, has embedded the Geppetto electronic design application into its Seeed platform. Seeed users can now go straight from creating a design, to manufacturing a working printed circuit board in just one session.
Geppetto is a ground-breaking cloud-based design tool that allows anyone to design electronics. Until now, Gumstix was the only company using Geppetto to create and manufacture custom electronics. Now users can create Geppetto-based designs and have them manufactured by Seeed. A hardware design can be completed in minutes, and ready to ship from 7 – 20 working days.
“Exciting new electronics are being conceived by programmers who are putting their innovative software in specialized devices,” said W. Gordon Kruberg, M.D., head of Modular Hardware, Altium, LLC.” We are thrilled to be working with Seeed to put Geppetto’s power of authorship and design in the hands and minds of this new generation of makers.”
Geppetto Key Capabilities:
Custom Web-design tool – embedded directly into the Seeed ecosystem, Geppetto provides a simple drag and drop design platform for all levels of designers enabling them to quickly build production-ready prototypes for IoT and AI applications.
Design to Build – Geppetto allows Seeed users, makers or professional engineers, to design custom hardware from the Seeed component library. The Board Builder is a menu driven application that allows users to rapidly populate a Geppetto board, making the design/prototype process trivially easy.
Rapid Manufacturing – Seeed can manufacture and deliver custom hardware directly, or with partners.
About Geppetto
Geppetto® is a free online design tool that lets almost anyone create electronic device designs. Hardware design can be created in minutes, complete with BOM documentation and pricing. Users can create multiple projects and go straight from a design to a production ready order in one session. To learn more about Geppetto’s web design tool integration into Seeed visit http://geppetto.seeedstudio.com/
About Altium
Altium LLC (ASX:ALU), a global software company headquartered in San Diego, Calif., is accelerating the pace of innovation through electronics. From individual inventors to multinational corporations, more PCB designers and engineers choose Altium software to design and realize electronics-based products. Products include Altium Designer®, Altium Concord Pro™, Altium 365®, Altium NEXUS®, CircuitMaker®, CircuitStudio®, Octopart®, and TASKING®. To learn more about Altium, visit www.altium.com.
About Seeed
Seeed provides the latest open hardware for IoT, AI and Robotic systems, and help developers scale new applications. Founded in 2008, Seeed is based in Shenzhen with branch offices in the EU, US and Japan. By partnering with top tech providers, we speed up the application of new technologies across industries. By enabling global developers to solve real-world problems, we encourage collaboration for a sustainable future. Visit www.seeed.cc for more information
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