The common ESD diode replacement models for Nexperia’s LIN/CAN(FD)/FlexRay bus are listed in Table 1 as follows:

Table 1:

If you are seeking for an alternative to Nexperia’s static diodes, you can contact the sales staff of Leiditech Shanghai.

To determine whether an ESD diode can be used as a substitute, the following points should be considered:

1) Is VRWM close?

2) Is the anti-static performance comparable?

3) Is VBR close?

4) Is IPP close?

5) Is CJ close?

Below, a comparison of Leiditech’s several alternative model parameters will be presented.

1. LIN Bus Electrostatic Protection Scheme and Domestic Alternatives

LIN (Local Interconnect Network) bus is a low-cost serial communication network used to achieve distributed electronic system control in automobiles. LIN bus is a supplement to other automotive multi-networks such as Controller Area Network (CAN), and is suitable for applications where there are no high requirements for network bandwidth, performance, or fault-tolerant functions.

Comparison of Domestic Alternative Models and Parameters of PESD1LIN

By comparing, the parameter performance of Leiditech PESD1LIN is superior to Nexperia’s PESD1LIN.

2、CAN(FD)/FlexRay Bus static protection scheme and domestic alternatives

The CAN (FD)/FlexRay bus requires an effective protection scheme to prevent electrostatic discharge (ESD) and surge interference, ensuring the reliability and stability of communication. The protection scheme diagram for Leiditech Shanghai CAN (FD) is as follows

The above scheme uses Shanghai Leiditech’s SMC24LVQ, SMC27LVQ and SMC36LVQ for protection. The reason for having three options is that customers can choose to use them based on the working voltage.

Domestic alternative for CAN(FD)/FlexRay bus

According to the Nexperia model listed in Table 1, the parameters of each model vary slightly. The table presents a detailed comparison of the parameters between the domestic alternative models from Leiditech and these models:

3、Application fields

The LIN, CAN(FD) and FlexRay bus ESD protection devices are the “safety guards” of modern automotive electronic systems. They are widely used in various fields such as automobile body control (like windows, door locks, and lights), powertrain (engine and transmission control), chassis safety (ABS, airbags), and intelligent driving (radar, cameras). In the vehicle network, these sophisticated chips are highly susceptible to electrostatic discharge, which can cause communication interruptions or hardware damage. Leiditech Shanghai dedicated ESD protection devices ensure the integrity of bus signals and system reliability by providing precise voltage clamping and high-speed energy dissipation. With the development of automotive intelligence, low-capacitance and high-strength protection devices that comply with the AEC-Q101 standard have become indispensable key components for ensuring the stable operation of vehicle network communications.

Leiditech Electronics is committed to becoming a leading brand in electromagnetic compatibility solutions and component supply, offering products such as ESD, TVS, TSS, GDT, MOV, MOSFET, Zener, inductors, etc. Leiditech has an experienced R&D team that can provide personalized customization services based on customer needs, offering the best solutions to customers.

#Leiditech #ESDProtection #AutomotiveElectronics #LINBus #CANFD #FlexRay #NexperiaAlternative #MadeInChina #VehicleNetwork #ElectrostaticProtection #AutomotiveInnovation #SmartMobility #EMC #ElectronicComponents

The Dutch government’s asset freeze and equity custody of Nexperia Semiconductor，Triggering global impact Automotive Electronics supply chain “dominoes effect”。As a vehicle specification level LIN/CAN Core supplier of bus protection devices，Nexperia delivery cycle from 8 Extend the week to several months，Partial models are temporarily suspended from accepting orders。The purchasing director of a certain new energy vehicle company admitted frankly：“A bus protection device that costs tens of yuan，Almost caused the entire production line to shut down。” What’s even more tricky is，After Nexperia was entrusted, there was a technical support gap，There is no response to the original adaptation issue，Enterprises are caught in “There are problems without solutions” The desperate situation。

Transformation：Accurate implementation of Leiditech car standard level alternative solution

CAN (FD)/FlexRayBus requires effective protection scheme，to prevent electrostatic discharge（ESD）And surge interference，Ensure the reliability and stability of communication。Shanghai

LeiditechCAN(FD)The protection scheme diagram is as follows：

Shanghai Leiditech launches targeted vehicle specification level ESD Protection substitution matrix achieve “Parameter matching + Seamless switching ”。In the core plan，Leiditech PESD1LIN Reverse work voltage（VRWM）、The anti-static ability is superior to the same model of Nexperia；SMC24LVQ Can be directly pin-pin alternative to Nexperia PESD2CANFD24UT-Q，adopt GPP Process passed AEC-Q101 authentication through — 40℃to 125℃Wide temperature test To lower the threshold for transformation Provided by Leiditech “24 Hourly part number matching + 3 Tian Compatibility Test + 7 Delivery of Tian Sample” The Three Fast Services A commercial vehicle enterprise 48 Complete zero shutdown switching of the production line within hours。

Harvest：Dual value of supply chain stability and performance upgrade

After transformation，A certain new energy vehicle company EMC Test pass rate 100%，Batch use for three months with zero malfunctions，The delivery cycle has been shortened to 4–6 week。Shanghai Leiditech Car Regulation encapsulation Monthly production capacity of the base 500 Ten thousand pieces Not affected by the European energy crisis , can expand production as needed Annual demand 100 Ten thousand calculations Enterprise procurement cost reduction 15%-20%，Annual savings and cost overruns 200 Ten thousand yuan achieve “Supply chain security + economic benefits” Win-win situation。

#AutomotiveElectronics #SupplyChainCrisis #NexperiaCrisis #ESDProtection #CANbus #FlexRay #Leiditech #EVManufacturing #AECQ101 #SemiconductorSolutions #ChinaChipAlternative #AutoTech #SmartManufacturing #ComponentShortage #AutomotiveEngineering

一、The Principle, Structure and Application of Infrasound Sensors

Working principle: Infrasound sensors are used to detect sound wave signals with frequencies below 20Hz. The core principle is to convert mechanical vibrations into electrical signals. Different types of sensors achieve this conversion based on different physical mechanisms. Their principle characteristics, applicable models, and typical application scenarios are summarized as follows:

Leiditech is committed to becoming a leading brand in electromagnetic compatibility solutions and component supply. It offers a wide range of products including ESD, TVS, TSS, GDT, MOV, MOSFET, Zener, inductors, etc. Leiditech has an experienced R&D team that can provide personalized customization services based on customer needs, offering the most superior solutions to customers.

If you’d like to learn more or have any questions, don’t hesitate to reach out:

[sales16@leiditech.com]

Visit us at [en.leiditech.com]

#InfrasoundSensors #SensorProtection #ESDProtection #SurgeProtection #IndustrialSensors #DefenseTech #EnvironmentalMonitoring #SmartSafety #Leiditech #ElectromagneticCompatibility #CircuitProtection #TechInnovation #IoTProtection #EngineeringSolutions

一、The Principle, Structure and Application of Infrasound Sensors

Working principle: Infrasound sensors are used to detect sound wave signals with frequencies below 20Hz. The core principle is to convert mechanical vibrations into electrical signals. Different types of sensors achieve this conversion based on different physical mechanisms. Their principle characteristics, applicable models, and typical application scenarios are summarized as follows:

Leiditech is committed to becoming a leading brand in electromagnetic compatibility solutions and component supply. It offers a wide range of products including ESD, TVS, TSS, GDT, MOV, MOSFET, Zener, inductors, etc. Leiditech has an experienced R&D team that can provide personalized customization services based on customer needs, offering the most superior solutions to customers.

If you’d like to learn more or have any questions, don’t hesitate to reach out:

[sales16@leiditech.com]

Visit us at [en.leiditech.com]

Replacing TI’s TPD4S012DRYR with Leiditech Part No.​

Looking to substitute TI’s TPD4S012DRYR? Leiditech offers four reliable alternatives: ULC051510TP6, LC0542T5, ULC1654N, and ULC0503NL.​

1. ULC051510TP6: A Perfect Pin — to — Pin Replacement​

The standout choice is ULC051510TP6, which delivers a complete drop — in replacement for TPD4S012DRYR. Both share the same 1510TP6 package, with identical protective pin layouts and matching solder pad sizes. Critical pins like D+, D-, and ID (all IO pins) are fully compatible, with no functional differences. What’s more, Leiditech’s model boasts better performance parameters — making it a seamless upgrade.​

2. ULC1654N: Ideal for 15V VBus Applications​

If your design uses TPD4S012DRYR in a 15V VBus setup, ULC1654N is an excellent pick. It features a compact size while supporting both VBus and 5V IO applications, ensuring compatibility where it matters most.​

3. LC0542T5: Same Function, Different Package​

For engineers seeking functional parity with a different package, LC0542T5 fits the bill. While the package differs, its solder pad design is similar, and it matches TPD4S012DRYR in application and wiring — making it a viable alternative with minor layout adjustments.​

4. ULC0503NL: Streamlined Protection for USB 2.0​

TI’s TPD4S012DRYR includes an unused 5th pin, and Leiditech’s ULC0503NL mirrors this with unused pins 2 and 5. Though it has one fewer IO pin, it excels in USB 2.0 protection: under the same design conditions as TPD4S012DRYR’s USB OTG protection schematic, ULC0503NL reliably safeguards VBus and 2 DATA lines.​

Engineers can select the best fit based on their specific packaging, voltage, and pin count needs.​

Replacing Semtech’s RCLAMP0503N with ULC0503NL​

When it comes to Semtech’s RCLAMP0503N, Leiditech’s ULC0503NL is a game — changer. A side — by — side comparison of performance parameters, application schematics, and wiring diagrams confirms it’s a true pin — to — pin replacement. Not only does ULC0503NL match RCLAMP0503N in functionality, but it also offers superior parameters — ensuring a seamless, high — performance swap.​

At Leiditech, we’re committed to providing flexible, high — quality alternatives that simplify upgrades and reduce supply chain hurdles. Whether you need pin — perfect compatibility or enhanced performance, our ESD/TVS solutions deliver.​

#ESDProtection #TVSDiode #USBProtection #CircuitDesign #Leiditech #EngineeringSolutions #Semiconductor #ElectronicsDesign #TPD4S012DRYR #RCLAMP0503N #DropInReplacement #HardwareEngineering #PCBDesign #TechInnovation #DesignUpgrade #PowerElectronics #SupplyChainResilience

Leiditech’s DSK34L takes performance up a notch with an ultra-low forward voltage drop (Vf) as low as 0.3V — lower than standard Schottky diodes. It also features minimal leakage current (max 200uA), translating to higher efficiency and superior circuit performance.

Housed in a compact SOD-123FL package, it supports SMT mounting, perfect for high-density assemblies that save valuable PCB space.

Why Low Voltage Drop Matters?

Less voltage drop means less wasted power. For example: A conventional 45V Schottky with 0.58V Vf might hit 88% power conversion efficiency, while a low-drop Schottky at 0.42V can reach 92% — a 4% boost that cuts energy loss significantly.

Versatile Applications

Ideal for smart lighting, smart home devices, phone fast chargers, consumer electronics, switching power supplies, and inverters. Use it as a high-frequency, low-voltage, high-current rectifier, freewheeling diode, or protection diode. It also works as a rectifier in microwave communication circuits or small-signal detection diodes.

Efficiency meets versatility — this is the DSK34L difference.

#ElectronicsDesign #PowerEfficiency #SchottkyDiode #DSK34L #SmartTech #IoTDevices #FastCharging #PCBDesign #Leiditech #TechInnovation #EngineeringExcellence #LowVoltageDrop #SMTAssembly #EnergyEfficientTech

Key advantages of PTVS0542H100

The PTVS0542H100 shines in protecting 5V power supplies, 4.5V high-current Vbus lines, and more during plugging/unplugging scenarios.

Why It’s a Seamless Swap?

Our EMC experts checked the critical parameters for ESD diode replacement, and the results speak for themselves:

1. VRWM (Working Voltage) — Nearly identical

2. ESD protection capability (air & contact) — On par

3. VBR (Breakdown Voltage) — Closely matched

4. IPP (Peak Pulse Current) — Similar performance

5. CJ (Junction Capacitance) — Almost the same

Plus, both use the same DFN1006 package, making drop-in replacement a breeze.

Applications of PTVS0542H100

deal for ESD and surge protection in:

• Mobile phone power supplies

• USB VBus lines

• Batteries

• Power lines

At Shanghai Leiditech, we specialize in R&D and sales of ESD/TVS products. We’re dedicated to safeguarding circuits from static interference and voltage fluctuations, serving industries like electronics, communications, computers, automotive, and medical. With an experienced R&D team, we also offer custom solutions. Our goal? To be a global leader in ESD/TVS supply, delivering top-tier solutions and service.

#ESDProtection #TVSDiodes #Leiditech #CircuitProtection #ElectronicsDesign #PowerSupplyProtection #USBProtection #SemtechAlternative #EngineeringSolutions #TechInnovation #ElectronicsManufacturing #ComponentReplacement #PCBDesign #DropInReplacement

As a semiconductor Manufacturer focusing on the research and development and production of anti-static and anti-surge TVS/ESD and related EMC components, this exhibition gave us a deeper understanding of the Vietnamese semiconductor market and gained many valuable business opportunities.

Exhibition overview and market opportunities

The Vietnam NEPCON Electronics Show has become a key showcase platform for Vietnam’s electronics industry, which is experiencing the fastest growth in Southeast Asia’s manufacturing sector. This year’s exhibition spans 15,016 square meters and covers multiple fields including SMT, testing technology, equipment, supporting industries, and intelligent manufacturing.

Vietnam’s semiconductor market has witnessed rapid growth in recent years, reaching a scale of $18.23 billion in 2024 with an average annual growth rate of 11.48%. The country’s share in global semiconductor packaging and testing has risen to 15%. Recently, the Vietnamese government enacted the “Science and Technology Innovation Law” and the “Digital Technology Industry Law”, allocating 3% of its national budget to technological innovation development. This policy environment significantly boosts confidence for semiconductor enterprises.

Exhibition display and product highlights

As a high-tech enterprise and specialized, refined and new small and medium-sized enterprise, Leiditech focuses on the company’s independent research and development of anti-static TVS/ESD and related EMC components, including:

✱Transient voltage suppression diode (TVS): applicable to communication security, automotive electronics and other fields

✱ Electrostatic protection element (ESD): provides reliable protection for precision electronic equipment

✱ Semiconductor discharge tube (TSS): with fast response and high surge absorption capacity

✱ Varistor (MOV): widely used in power line protection

These products are certified by UL, VDE, ROHS and other standards, in line with IEC and FCC standards. We specially show the new ULC0542CQ and other automotive grade products launched in 2025, which have broad application prospects in the automotive electronics field.

Customer communication and cooperation opportunities

During the exhibition, we had in-depth communication with electronics manufacturing enterprises from Vietnam and other Southeast Asian countries. The main types of customers we contacted include:

✱ EMS/Manufacturer: explore the application of circuit protection components in OEM production

✱Automotive electronics manufacturers: technical requirements and cooperation for AC automotive-grade products may be possible

✱ Communication equipment suppliers: Introducing our protection solutions for 5G infrastructure

✱ Medical electronics enterprises: discuss the use of high reliability components in medical equipment

Notably, we have established preliminary partnerships with several Vietnamese electronics manufacturers who have shown strong interest in our Leiditech EMC protection solutions. Additionally, buyers from Malaysia and Thailand have recognized the market potential of our products in Southeast Asia.

Market observation and future planning

Through this exhibition, we have gained a deeper understanding of Vietnam’s potential as the “next electronics manufacturing center in the world”. Many international giants have established production bases in Hanoi and surrounding provinces and cities, forming synergies with Samsung, Intel and others.

In the first half of 2025, China’s integrated circuit exports to Vietnam reached $12.3 billion, accounting for 13.6%, which provides a huge business opportunity for China semiconductor Manufacturer like us.

Based on the results of this exhibition, we plan:

✱ Strengthen market layout in Vietnam: consider setting up local technical support team in Vietnam

✱ Deepen product localization: develop a product line more in line with the market demand of Vietnam

✱ Participate in more industry events: plan to participate in SEMI-Vietnam Semiconductor Expo in November 2025

✱ Establish local partnerships: work with distributors and system integrators in Vietnam

Summary and outlook

The 2025 Vietnam NEPCON Electronics Exhibition provided us with a valuable platform to showcase our technical capabilities, understand market trends, and establish business connections. Although detailed statistics on the specific exhibition outcomes have not been fully compiled, based on on-site feedback, we successfully demonstrated Shanghai Leiditech Electronics’ technical expertise and product advantages in circuit protection to the electronics manufacturing industry across Southeast Asia.

The rapid development of Vietnam’s semiconductor market and the strong government support have filled us with confidence in this market. As a member of China’s semiconductor industry chain, we Leiditech will continue to focus on technological innovation, providing higher-quality ESD/TVS protection solutions for global customers including Vietnam, and jointly promote the progress and development of the electronics manufacturing industry.

#Leiditech #NEPCONVietnam2025 #SemiconductorSolutions #TVS #ESD #CircuitProtection #AutomotiveElectronics #VietnamTech #ElectronicsExpo #SmartManufacturing #EMC #MadeForInnovation #VietnamSemiconductor #TechTradeShow #EMSSolutions #AsiaElectronics #IoTProtection #ElectronicsManufacturing #ESDProtection #GlobalExpansion #TechBlog

l SD memory card specs (Version 3.01: SDXC, SDHC, SD cards)

l SD IO card specs (Version 3.0)

l JESD84-B51 (eMMC/MMC cards) and JESD84-B45 compatibility

The eSDHC interface enables critical functions like fetching reset configuration words (RCW), preboot initialization (PBI), and boot images from SD cards or eMMC. It also serves as a reliable storage interface, seamlessly supporting 1.8V eMMC due to matching 1.8V signaling on both components.

The interface protection details are as follows.

ESD Protection with Leiditech SR05

For robust ESD protection of the 1.8V SDHC interface, the Leiditech SR05 is the go-to solution.

Key Notes on SDHC Operation:
When configured for SDR speed mode with 1.8V signaling, the SD card retains 1.8V output even after CMD0 commands, per SD specifications. A power cycle is required to reset signaling back to 3.3V, so ensure a brief power-off period post-reset.

PCB ESD Design Best Practices

To maximize protection effectiveness:

1. Place the SR05 as close to the input connector/terminal as possible.

2. Minimize trace length between the SR05 and protected lines.

3. Avoid parallel routing of signal paths.

4. Separate protected and unprotected wires to prevent crosstalk.

5. Reduce all conductive loops, including power and ground paths.

6. Shorten ground transient return paths to minimize impedance.

7. Avoid shared transient return paths to common connection points.

8. Use a solid ground plane (with vias for multilayer PCBs) for optimal shielding.

Leiditech’s SR05 is widely trusted for ESD protection in USB 2.0, I/O interfaces, and more. Leiditech also offers free electromagnetic compatibility (EMC) lab access to support design validation and testing.

𝗙𝗶𝗻𝗱 𝗼𝘂𝘁 𝗺𝗼𝗿𝗲:[en.leiditech.com]

𝗖𝗼𝗻𝘁𝗮𝗰𝘁 𝘂𝘀: sales16@leiditech.com

#ESDProtection #EmbeddedDesign #SoC #HardwareDesign #PCBDesign #ElectronicsEngineering #eMMC #SDCard #IoTDesign #Leiditech #TechTips #SDHC #SignalIntegrity #1point8VDesign #ReliabilityMatters

People often refer to the serial port in embedded systems as UART (Universal Asynchronous Receiver Transmitter). Leiditech electronic engineers learned that the embedded system UART is a very common asynchronous serial communication interface, which is often used to debug the hardware circuits and software programs of PCB boards. Below the UART interface diagram:

UART has four pins: VCC, GND, RX, and TX, as shown in the following figure.

The TTL level used is 0 for low level (0V) and 1 for high level (3.3V or 5V).

2. UART interface has no data output and is on strike

For electronic engineers, UART is like an endoscope, which can detect the internal operation of chips that cannot be touched or seen. Its importance is self-evident, and it can be used. One day, it suddenly went on strike and didn’t respond to any manipulation. Do this at this time. If you don’t work, I’ll switch. The MCU/SOC can only be disassembled and replaced with a new one, and at this point, the UART starts working again, but this is no longer the original one.

3. Why UART is prone to breakage

Leiditech Electronic Engineer has compiled the following possible causes:

(1) Voltage too high or too low: UART interfaces typically require a specific voltage range to function properly. If the input voltage exceeds its acceptable range, it can cause damage. This situation is unlikely.

(2) Live plugging and unplugging of connectors causes surge voltage exceeding the interface level range. This situation often occurs.

(3) Electromagnetic interference: UART communication lines may be subject to electromagnetic interference, such as power interference, motor drive interference, high-frequency signal interference, etc. These interference signals may cause UART to receive incorrect data or damage. This situation is possible.

(4) Electrostatic discharge: Electrostatic discharge is a common cause of damage to electronic devices. If appropriate protective measures are not taken, the UART interface may be damaged when static electricity is discharged from the human body. This situation is most likely.

(5) Overcurrent or overload: If the current on the UART interface exceeds its design limit, it may cause component damage. This may be caused by a short circuit or sudden increase in current in external devices. This situation is unlikely unless there is a short circuit.

All five of the above may cause damage. So what approach should we take?

4. UART interface protection measures

Engineers often ask us how we can avoid damage to the UART interface. Leiditech Electronics engineers have compiled the following preventive measures:

(1) Firstly, use voltage within the level range of the UART interface: ensure that the power supply voltage of the UART interface is within the specified range, and each SOC has pin level labeling instructions.

(2) Avoid plugging and unplugging connectors while the PCB board is powered, as this can easily cause surges that exceed the UART interface level and cause permanent damage. Of course, we can increase the serial resistance and ESD to reduce surges and avoid damage to the UART interface.

(3) Do a good job in electromagnetic interference protection: When designing circuits, layout and shield the lines reasonably to reduce electromagnetic interference. Place the power supply and motor driver with strong electromagnetic interference at one end of the PCB, and place the high-frequency or sensitive signal line at the other end of the PCB board away from interference.

(4) Prevention of electrostatic discharge: Use anti-static tools or wear anti-static gloves and other measures, grounding reasonably to avoid static damage (which we often fail to implement due to trouble). So it is very important to add ESD component protection on the circuit. One end of the ESD is connected in parallel to the communication lines TXD and RXD, and the other end is grounded. Moreover, connecting small resistance values in series on the TXD and RXD lines has a better effect. I have learned this plan from my experience, as shown in the following figure.

(5) Limit current: Ensure that the current on the UART interface does not exceed its design limit. If external devices need to be connected, please ensure that their current meets the specifications of the UART interface, and regularly check the wiring terminals to avoid short circuits.

(6) In general, attention should be paid to the design of wiring first, and then ESD protection should be added. Of course, in addition to the serial UART, the JTAG interface is also a commonly used debugging interface for electronic engineers, so the above protective measures also need to be added. The electronic protection circuit of Shanghai Leiditech is as follows.

5. Shanghai Leiditech Electronics provides UART and JTAG interface protection measures

1. Serial UART interface protection circuit

2) JTAG interface protection circuit

Leiditech Electronics provides customers with electromagnetic compatibility EMC design services, providing laboratory testing for free, efficient and cost controlled design. We strive to quickly pass EMC projects and improve product reliability.

Leiditech Electronic Electromagnetic Compatibility Laboratory provides free testing, peripheral electrostatic protection reference circuits, and domestic certification documents. Contact Andy 18016225001.

#UART #EmbeddedSystems #MCU #SOC #ESDProtection #CircuitDesign #HardwareDebugging #ElectronicsEngineering #EMC #Leiditech #SerialCommunication #TechTips #EngineeringSolutions #IoTDesign #PCBDesign

In the surge protection of signal lines, a small resistor is often connected as a protective device to suppress surge current and limit current. But for greater current and voltage protection, a TVS or ESD is also required to provide higher surge protection for the subsequent stage chips.

How to place the series resistor R and ESD? The series resistor is placed close to the protected chip, and the ESD is placed close to the interface; Or is the ESD placed close to the chip, and the series resistor placed close to the interface. Shanghai Leiditech engineers have found that the anti surge level varies depending on the placement.

2. Theoretical analysis

In the case shown in Figure 1, when ESD acts, I=I1+I2, and I>I1, a greater current will flow on R1 than in ESD. Although the protected circuit is protected to some extent in this situation, the resistance R1 cannot withstand the test of high currents and is damaged, resulting in interface and system failures.

In the case shown in Figure 2, when the ESD action protection is effective, the impedance of the ESD is very low, and most of the current flows through the ESD, i.e. I2. However, the current I1 flowing through R1 is much smaller than I2, which is even smaller than I. Although in this case, the ESD needs to withstand a larger current, as shown in Figure 1, it is more capable of withstanding large currents compared to resistors, so the anti surge level of the chip has actually increased.

In actual tests, the anti surge voltage capability of the signal interface in Figure 1 is much worse than that of the interface in Figure 2. Shanghai Leiditech Electronic Engineers often find that the failure of the interface in Figure 1 is caused by damage to the resistance connected in series to the interface circuit, while the ESD is not damaged; The interface failure in Figure 2 is caused by ESD breakdown and short circuit, and the resistance is not damaged. Based on this, engineers from Shanghai Leiditech have concluded that the resistance is placed close to the chip, while the ESD is placed close to the interface, which has a stronger protective ability.

It should be noted that when designing surge protection circuits, appropriate series resistors and TVS should be selected based on the specific application requirements. The selection of resistance value is usually between tens to hundreds of ohms, and consideration should be given to balancing signal quality and protection effect. The rated voltage of TVS should be greater than the expected overvoltage level.

3. Shanghai Leiditech Interface Circuit Protection Circuit Recommendation

1. RS485 interface surge protection circuit

2) RS232 interface surge protection circuit

3) RS485 interface surge protection component list

4) RS232 interface surge protection component list

If you’d like to learn more or have any questions, don’t hesitate to reach out:

Visit us at [en.leiditech.com]

#ESDProtection #SurgeProtection #CircuitDesign #ElectronicsDesign #RS485 #RS232 #TVSDiode #PCBLayout #EngineeringTips #EmbeddedSystems #ShanghaiLeiditech #SignalIntegrity #HardwareDesign #ElectronicsManufacturing

The SDA3311DN is primarily designed for electrostatic surge protection in 3.3V power supplies, gaining popularity in space-constrained small electronic devices.

Key advantages of Leiditech’s SDA3311DN:

l High IPP (65A)

l Small loop area

l Low clamping voltage (Vc)

l Effective against both static electricity and certain surges

Critical parameters for ESD diode replacement:

1. VRWM (Working Voltage)

2. ESD protection capability

3. VBR (Breakdown Voltage)

4. IPP (Peak Pulse Current)

5. CJ (Junction Capacitance)

Both the SDA3311DN and AZ5883–01F feature DFN1006 packaging. Their VRWM, VBR, IPP, CJ, and ESD (air/contact) parameters are nearly identical, making the SDA3311DN a fully compatible replacement.

Applications for SDA3311DN:

l Mobile phone power supplies

l Handheld devices

l USB VBus

l Batteries

l ESD protection for power lines in electronic equipment

Shanghai Leiditech specializes in R&D and sales of ESD TVS products, protecting circuits from static interference and voltage fluctuations. Our products serve electronics, communications, computers, automotive, and medical industries. With an experienced R&D team, we offer customized solutions to meet specific customer needs, aiming to become a global leader in ESD TVS supply.

#ElectronicsDesign #ESDProtection #TVSDiode #Leiditech #AZ5883Alternative #CircuitProtection #TechUpgrade #EngineeringSolutions #SemiconductorNews #PowerSupplyDesign #PCBDesign #MobileTech #USBProtection #ESDGuard #ElectronicsIndustry #ComponentReplacement

The following is a summary of the main application fields of SE3401 (P-channel MOSFET), taking into account its low on-resistance, high switching efficiency and small package (SOT-23) features.

一、Key Features and Application Foundations

l Electrical Parameters: Rated voltage (VDS): -30V; Current: -5.0A.

l Low On-Resistance: 41mΩ @ 10V, 50mΩ @ 4.5V, reducing power loss and heat generation.

l Package Advantage: SOT-23 package, compact size, ideal for high-density circuit designs.

二、Applications in Power Management and Protection Circuits

1. Reverse Protection Circuits

Replaces diodes with lower voltage drop (only 41mΩ @ 10V), minimizing useless power loss;

Quickly cuts off during power reverse connection to prevent device damage.

2. Load Switches and Power Distribution

Used for power on/off control in mobile devices and motherboard circuits, supporting PWM voltage regulation;

Controls power for RF amplifiers in 5G small base stations with fast response time (approximately 60ns).

三、Applications in Portable Electronic Devices

1. Battery Management Systems

Mobile phone/lithium battery protection boards: Prevents overcharge and over-discharge, supports reverse connection protection;

Power banks and e-cigarettes: Efficient switch control extends battery life.

2. Power Control for Small Devices

MP3 players, Bluetooth headsets, and GPS devices: Low-power design adapts to USB-powered scenarios.

四、Applications in Power Supplies and Motor Drives

1. DC-DC Conversion and Inversion：

Power inverters and car DVD players: Supports -30V high-voltage switching, compatible with automotive electronics requirements;

Synchronous rectification circuits: High-speed switching improves conversion efficiency.

2. Motor and LED Drives

Micro motors (e.g., drones, power tools): Provides stable driving current;

LED lighting/displays: Enables constant current regulation to ensure stable brightness.

五、Applications in Industrial and New Energy Fields

1、Industrial Equipment

Stepper motor drives and drill tools: High voltage resistance and shock resistance;

Industrial switching power supplies: Low heat loss design reduces heat dissipation requirements.

2、Green Energy Systems

Photovoltaic inverters and charging piles: Enables efficient power conversion;

Automotive-related: Automotive HID ballasts and electric bicycle controllers.

In summary, the SE3401 stands out with three key advantages: low internal resistance, fast response, and small size, making it an ideal choice for power protection, portable devices, motor drives, and industrial systems. For domestic alternative needs, Leiditech offers pin-to-pin compatible solutions with lower cost and comparable parameters. For specific designs, refer to the SE3401 device datasheet to ensure compatibility

Leiditech is committed to becoming a leading brand in electromagnetic compatibility (EMC) solutions and component supply, offering products such as ESD, TVS, TSS, GDT, MOV, MOSFET, Zener, and inductors. With an experienced R&D team, Leiditech provides customized services to meet customer needs and deliver high-quality solutions.

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Myth 1: “A lightning rod stops all lightning damage”

Many think a lightning rod is enough — but it’s not true.

A historic building in Beijing had lightning rods, yet its fire control cabinets still broke after a strike. In a Huairou village, working lightning devices couldn’t save villagers’ TVs and computers. The culprit? Lightning Electromagnetic Pulse (EMP).

Like ripples in water, EMP spreads through wires and signal lines. Even if lightning hits 100 meters away, this “electric ripple” (called induced lightning) can damage devices. Lightning rods only handle direct strikes, but induced lightning causes 90% of damage by traveling through lines to core components.

Leiditech’s fix: “Full-link protection” — use lightning rods + grounding for direct strikes, add surge protectors (SPD) on internal lines, and equip devices with scenario-specific protectors.

Myth 2: “Lightning components mean no more worries”

Installing protectors isn’t enough — wrong use is riskier than no use! Leiditech’s expert warns: “Wrong selection, bad installation, or no maintenance makes protection useless.”

Common mistakes:

l Broken protection chains: Loose SPD connections or grounding wires (like in a Beijing factory) caused 20% more damage than unprotected gear.

l Mismatched components: Using weak civil-grade protectors (≤5kA) in critical fire cabinets (needs 10kA+); using industrial-grade protectors for home routers slows networks.

l Poor wiring: Power and signal lines running too close (needs ≥30cm space per GB50343). EMP jumps between lines, bypassing power protectors.

Check 3 things: ① Protectors match device ports; ② Use a milliohmmeter to ensure wire resistance ≤50mΩ; ③ Fix line layouts to block risks.

Myth 3: “Only outdoor devices need protection”

Indoor gear is at high risk! All 4 lightning incidents reported in Beijing this year damaged indoor electronics. EMP penetrates walls via power lines, signals, or metal pipes — lightning 30km away can harm them.

Indoor “danger zones” to watch:

l Fire/industrial control gear: Even with lightning rods, they need protection. Add Leiditech’s 10kA 220V protectors (passes IEC61000–4–5 4kV~8kV tests) and GDT+ESD signal protectors (≤1pF).

l Home appliances: 70% of storm-damaged TVs lack built-in protectors and stay plugged in — wires act like “antennas” for EMP. Use surge-protected sockets (with Leiditech’s 220V solution).

l Smart devices: Wi-Fi modules in fridges/robot vacuums are fragile. Add Leiditech’s 220V protection to their adapters to avoid glitches.

Leiditech’s Lightning Solutions

48V DC protection: GDT+MOV+TVS 2-stage defense (handles 6kV surges, IEC61000–4–2 Level 4).

220VAC protection: GDT+MOV components (4kV~8kV surge resistance).

24VDC low-voltage protection: Small LM1K24CA (SMB) for 2kV surges, cuts LDO/DC-DC costs.

Gigabit Ethernet Lightning Protection：For outdoor 1000M Ethernet port surge protection. Leimou adopts two-stage protection, ensuring reliable operation and high-temperature signal integrity. Complies with IEC61000–4–2 Level 4 (contact discharge 30kV, air discharge 30kV) and IEC61000–4–5 (10/700μs, 40Ω, 6kV, ±5 times). No packet loss during high-temperature transmission.

POE Outdoor Lightning Protection (6kV)：For outdoor POE Ethernet port surge protection. Leimou adopts two-stage protection, ensuring reliable operation and high-temperature signal integrity. Complies with IEC61000–4–2 Level 4 (contact discharge 30kV, air discharge 30kV) and IEC61000–4–5 (10/700μs, 40Ω, 6kV, ±5 times). No packet loss during high-temperature transmission.

CAN Interface ESD & Surge Protection：Leiditech adopts low-residual-voltage TSS for effective interface protection. With ns-level response time, TSS provides both surge and ESD protection while ensuring signal integrity. Complies with IEC61000–4–2 ESD Level 4 (contact discharge 8kV, air discharge 15kV); IEC61000–4–5 surge (10/700μs, 8kV; 8/20μs, 2kV).

RS485/RS422 Interface ESD & Surge Protection：Leiditech uses low-residual-voltage TSS to effectively protect RS422/RS485 chips. Featuring ns-level response time, TSS offers surge and ESD protection with guaranteed signal integrity. Complies with IEC61000–4–2 ESD Level 4 (contact discharge 15kV, air discharge 8kV); IEC61000–4–5 surge (10/700μs, 6kV). For higher surge level requirements, P0080SD can be replaced.

If you’d like to learn more or have any questions, don’t hesitate to reach out:

[sales16@leiditech.com]

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#LightningProtection #SurgeProtection #EMCSolutions #Leiditech #ElectromagneticCompatibility #IndustrialSafety #SmartHomeProtection #ESD #TVS #MOV #GDT #ProtectYourTech #SmartSafety #ElectricalEngineering #BuildingSafety #HomeElectronics #TechMythsDebunked

The SMDA05N is mainly used for protection in 5V power supplies, 4.5V high-current Vbus lines, and plug-in scenarios.

Key advantages of SMDA05N:

• High IPP (50A)

• Small loop area

• Low clamping voltage (Vc)

• Effective against both static electricity and certain surges

Critical parameters for ESD diode replacement:

1. VRWM (Working Voltage)

2. ESD protection capability

3. VBR (Breakdown Voltage)

4. IPP (Peak Pulse Current)

5. CJ (Junction Capacitance)

Both SMDA05N and AZ5815–01F come in DFN1006 packaging. Their VRWM, VBR, IPP, CJ, and ESD (air/contact) parameters are nearly identical, making SMDA05N a fully compatible replacement.

For bidirectional needs, choose SMDA05CCN.

Applications of SMDA05N:

l Mobile phone power supplies

l USB VBus

l Batteries

l ESD protection for power lines and other surge scenarios

Unidirectional: SMDA05N
Bidirectional: SMDA05CCN

Shanghai Leiditech specializes in R&D and sales of ESD TVS products, dedicated to protecting circuits from static interference and voltage fluctuations. Our products serve a wide range of industries, including electronics, communications, computers, automotive, and medical. With an experienced R&D team, we offer personalized customization services to meet customer needs, aiming to become one of the world's leading ESD TVS suppliers, providing top-quality solutions and services.

If you’d like to learn more or have any questions, don’t hesitate to reach out:
[sales12@leiditech.com]
Visit us at [en.leiditech.com]

#ESDProtection #TVSDiode #CircuitProtection #ElectronicsDesign #PowerSupply #USBProtection #EngineeringSolutions #Leiditech #ElectronicsIndustry #ElectronicsComponents #SMDA05N #TechInnovation #EmbeddedSystems

USB 3.1 Gen 2 integrates Tx/Rx differential lines, boasting a speed of up to 10 Gbps. At such speeds, the capacitance of electrostatic discharge (ESD) protection components must be minimized to maintain signal integrity.

Solution: For ESD protection of USB 3.1 Gen 2 Tx/Rx lines, the capacitance should be 0.3 pF or less to ensure signal integrity, with an operating voltage of over 3.6 V. One viable solution is to use a 4-channel ultra-low capacitance ESD device for data lines (Tx, Rx), combined with a 2-channel low-capacitance ESD device for D+/D- lines, plus a single-channel ESD device for the VBUS line.

ESD Protection Solutions for USB 3.1 Gen 2 Applications

If you’d like to learn more or have any questions, don’t hesitate to reach out:

[sales16@leiditech.com]

Visit us at [en.leiditech.com]

#USB3_1Gen2 #ESDProtection #SignalIntegrity #HighSpeedDesign #PCBDesign #ElectronicsEngineering #ElectrostaticDischarge #USBDesign #TechSolutions #HardwareDesign #DFNPackage #DesignTips #EngineeringInsights

What is Smooth Clamp TVS

In this paper, Shanghai Leiditech Electronics will introduce a new type of Load dump protection smooth box TVS, which can effectively protect the circuit from the damage of voltage overload, at the same time, it can smooth voltage fluctuations, improve the stability of the circuit, and meet the requirements of vehicle regulations.

This new type of TVS adopts advanced box position technology, which can start immediately when the circuit voltage rises abnormally, clamp the excessively high voltage within a safe range, and effectively protect subsequent circuits. In addition, the TVS also has the ability to smooth voltage fluctuations, effectively eliminating voltage peaks in the circuit and stabilizing them at a lower level, thereby improving the stability of the circuit.

In addition, the TVS also has the advantages of fast response speed, strong pressure resistance, and high reliability. It is widely used in various electronic devices, especially for electronic devices that require high stability, and is an indispensable circuit component.

In a word, the new Load dump protection smooth clamping TVS is an efficient and reliable circuit protection component, which can protect the circuit from the damage of voltage overload and improve the stability of the circuit. I believe that this TVS will play an increasingly important role in various electronic devices in the future.

The device can pass the rigorous Load dump test of vehicle 12V system

This device also has the characteristics of low leakage current, low capacitance, and low distortion, which can work stably in various harsh environments. Therefore, it is also widely used in fields such as automotive electronics, communication equipment, and industrial control. If you need an efficient and reliable circuit protection component, this TVS will be your best choice.

This device has a patented ultra-low clamping voltage

Summary

The interface protection of electronic products requires the use of overvoltage protection devices. Many engineers are aware of the need to use protection devices, but due to improper selection or failure to follow the design principles of ESD circuit PCB, the product fails static or EMC testing, wastes manpower and financial resources, and causes product delays or over design, resulting in cost pressure. Leiditech Electronics provides customers with electromagnetic compatibility EMC design services, providing laboratory testing for free. We aim to efficiently and conveniently complete the design for our customers. We hope that more customers can quickly pass EMC’s projects and improve product reliability as much as possible.

Shanghai Leiditech Electronic Electromagnetic Compatibility Laboratory provides free testing and peripheral electrostatic protection reference circuits.

#TVSProtection #LoadDump #CircuitProtection #AutomotiveElectronics #ESDProtection #EMCDesign #ElectronicDesign #SmoothClampTVS #Leiditech #IndustrialElectronics #SmartEngineering #ElectronicsDesign #EMCCompliance #VehicleElectronics

The electrostatic charging test for automotive ESD is based on the GBT19951–2019&ISO10605 standards. This standard specifies ESD testing procedures for automotive, truck, and motorcycle components. During testing, professional electrostatic discharge guns and ESD testing equipment are used to apply electrostatic discharge to the surfaces of various parts of the car to simulate a real electrostatic discharge environment. During testing, attention should be paid to preventing harm to the testing personnel and the safety of the vehicle system itself.

Through ESD electrostatic charging tests, car manufacturers can evaluate the ability of car components to withstand electrostatic discharge to ensure the integrity and reliability of car systems. This helps to improve the reliability of the vehicle and reduce maintenance costs.

Picture caption:

(1) Field coupled flat plate (at least 10mm larger in all directions than DUT and at least 160mm in size) × 350mm, conical part connected to HCP);

(2) Field coupling strip supporting the wiring harness (width 40mm);

(3) Discharge island (diameter 80mm);

(4) Place a non-conductive block (r<2.5, height 50mm) for the DUT and wiring harness.

Note: The field coupling plate and field coupling strip are made of copper or brass, with a thickness of 0.5mm~2mm. The tolerance for dimensions is ± 5%.

Picture caption:

(1) Field coupled flat plate;

(2) Field coupling band;

(3) Discharge island;

(4) Insulating blocks for placing DUTs and wiring harnesses;

(6) DUT wiring harness;

(7) Battery;

(8) Peripheral or supporting devices;

(9) Artificial network (if used);

(10) Grounding reference points for batteries and supporting equipment;

(11) The nearest distance to ground of the DUT (if required);

(12) HCP, generator, and DUT safety grounding position I

(13) Two 470kQ high-voltage resistors connected to ground

(15) ESD generator host

Note: The tolerance for dimensions is ± 5%

Picture caption:

(1) Field coupled flat plate;

(2) Field coupling band;

(3) Discharge island;

(4) Insulating blocks for placing DUTs and wiring harnesses;

(6) DUT wiring harness;

(7) Battery;

(8) Peripheral or supporting devices;

(9) Artificial network (if used);

(10) Grounding reference points for batteries and supporting equipment;

(11) DUT nearest ground (if required)

(12) Safe grounding positions for HCP, generator, and DUT;

(13) Two 470k high-voltage resistors connected to ground;

(15) ESD generator host.

Note: The tolerance for dimensions is ± 5%

Picture caption:

(1) Field coupled flat plate;

(2) Field coupling band;

(3) Discharge island;

(4) Insulating blocks for placing DUTs and wiring harnesses;

(6) DUT wiring harness;

(7) Battery;

(8) Peripheral or supporting devices;

(9) Artificial network (if used);

(10) Grounding reference points for batteries and supporting equipment;

(11) DUT nearest ground (if required)

(12) Safe grounding positions for HCP, generator, and DUT;

(13) Two 470k high-voltage resistors connected to ground;

(15) ESD generator host.

Note: The tolerance for dimensions is ± 5%

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#AutomotiveTesting #ESDProtection #ISO10605 #GBT19951 #ElectronicsReliability #AutomotiveElectronics #ComponentTesting #ElectrostaticDischarge #AutomotiveStandards #VehicleSafety #AutoEngineering #EMCCompliance #TechBlog #EngineeringInsights

Key Applications

Ideal for surge and ESD protection in:

l 5V power supplies

l 4.5V high-current Vbus lines

l Plug-in interface protection

l Handheld device power systems

l USB VBus

l Battery surge scenarios

Why ESDA05CPX Stands Out

l Low clamping voltage (Vc): Only 8.2V, effectively safeguarding downstream circuits.

l High surge tolerance: IPP (peak pulse current) reaches 18A, resisting both static electricity and surges.

l Superior performance: Low leakage current and stable protection characteristics.

Critical Replacement Validation

A successful ESD diode replacement hinges on matching key parameters.

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#ESDProtection #ESDDiode #ElectronicsDesign #ComponentReplacement #USBProtection #PowerSupplyDesign #SurgeProtection #PCBDesign #EngineeringSolutions #Leiditech #ElectronicsManufacturing #TechTips

Automotive ambient lighting, a key element of emotional interior design, enhances driving experiences with warm (e.g., red) or cool (e.g., blue, purple) hues — adding vibrancy and reducing journey monotony, especially at night.

EMC Challenges in Ambient Lighting Surge Protection

Designing reliable surge protection for automotive ambient lighting involves addressing unique hurdles, as identified by Leiditech’s EMC experts:

1. Complex electrical environments: Interference from ignition systems, motors, and other electronics complicates protection.

2. Voltage fluctuations: Significant voltage swings during engine startup or device switching demand rapid response from protection components.

3. Multi-load setups: Multiple light strips/bulbs require individual protection, increasing circuit complexity and cost.

4. High reliability demands: Devices must perform stably under extreme temperatures, humidity, and vibration over long-term use.

5. Electromagnetic compatibility (EMC): Protection designs must avoid interfering with wireless systems (Bluetooth, GPS, etc.).

6. Regulatory compliance: Adherence to strict automotive standards is mandatory for safety and compatibility.

7. Size and cost constraints: Balancing protection performance with compact sizing and cost-efficiency, while meeting ISO 7637–2 testing requirements.

Solutions for Static & Surge Protection

Leiditech supports engineers in overcoming these challenges through tailored component selection, circuit optimization, and rigorous testing. Below are reference solutions for ambient lighting protection:

1. LED Driver Protection

For well-known automotive LED driver series, integrate ESD diodes at the power supply stage to shield driver chips from electrostatic surges.

2. Capacitive Touch Control Protection

The automotive-grade capacitive touch SoC chip TCAE11 — used in reading lights, ambient lighting, central control, and steering wheel interfaces — requires ESD diodes at power inputs to protect both the SoC and ambient lighting systems.

Recommended ESD Diodes for Ambient Lighting

Choose ESD diodes with compact packaging (ideal for tight automotive spaces), high surge current tolerance (IPP), and robust ESD immunity:

Key Recommendations

• For line protection, prioritize 18V/24V asymmetric ESD diodes like PESD1LIN or high-power 24V bidirectional devices.

• Leiditech offers customized ESD solutions paired with Lumissil and TCAE11 capacitive touch chips, tailored for automotive ambient lighting.

Need support with ambient lighting protection design? Connect with Leiditech’s EMC experts for personalized solutions.

Leiditech — Your Trusted Partner in Automotive ESD/TVS Protection.

#Leiditech #AutomotiveLighting #ESDProtection #TVSdiode #SurgeProtection #EMCdesign #AutomotiveElectronics #InteriorLighting #AmbientLight #LEDDriverProtection #CapacitiveTouch #ISO7637 #VehicleSafety #CarMods #EMCExperts #CircuitProtection #DesignEngineer #AutoInnovation