This topic will be shared from three aspects:

First, electronic system performance requirements and ESD problems

Second, integrated circuit ESD problem countermeasures

Third, integrated circuit ESD test and analysis

EMC issues in the development of industrial, consumer, and automotive electronics modules can result in extremely high development costs and wasted time. During the development process, in order to solve EMC problems, it is necessary to invest a lot of manpower, resources and time to test, improve and optimize, which increases the complexity and cost of development, and may also lead to project delays.

一、Electronic system performance requirements and ESD problems

l EMC problems in the development of electronic modules：Industrial, consumer and automotive electronic systems must meet ever-increasing performance requirements. With the development of intelligence and electrification, these electronic systems need to process more data and achieve more complex functions. This requires electronic modules to have higher integration, faster processing speed and lower power consumption, which increases the complexity of EMC issues.

l IC applications with high performance requirements：Due to the increasing performance requirements of electronic systems, more and more highly integrated, ESD-sensitive integrated circuits (ics) are being applied in this field. These ics are able to provide higher performance and more features, but they are also more susceptible to electrostatic discharge (ESD). When ESD occurs, it may produce a transient high voltage and high current inside the IC, which damages the internal structure of the IC, causing its function to fail or occur abnormalities. These failures will not only affect the normal operation of the automotive electronic system, but also may lead to safety risks.

l Impact of ESD on highly integrated microcontrollers：It mainly affects highly integrated microcontroller sensitive areas where oscillator units and phase locked loop (PLL) units are very sensitive to ESD processes. The oscillator unit is the clock source of the microcontroller and is responsible for generating a stable clock signal, while the PLL unit is used for frequency doubling, frequency splitting and phase adjustment of the clock signal. If these units are affected by ESD, it may cause instability or errors in the clock signal, which will affect the normal operation of the entire microcontroller. Current electronic applications cannot even achieve ESD immunity of 2kV in the worst case. This means that in practical applications, even relatively small ESD events can cause electronic devices to malfunction. In particular, for those microcontroller applications with radiators, experience has shown that they are particularly sensitive because the radiators may increase the ESD's coupling path, making it easier for ESD to affect the circuits inside the microcontroller.

Influence of heat sink on ESD sensitivity：Experience has shown that microcontroller applications with heat sinks are particularly sensitive to ESD (Figure 1). Figure 1 shows how ESD jamming works. This is because the ESD generator will couple the interference pulse to the heat sink, which creates a voltage difference between the heat sink and the electronic module, which in turn creates an electric field interference between the two. Due to the close distance between the heat sink and the IC, in the range of 0.2 to 1 mm, this high electric field strength can cause the IC to fail.

Figure 1 ESD interference working principle

Figure 2 Sensitive areas of the microcontroller detected by the source

Manual inspection of field-source integrated circuits (ics) will reveal that the phase-locked loop (PLL) and oscillator regions are particularly sensitive. Corresponding analysis of IC faults confirmed the presence of PLL and oscillator faults.

Follow the example in Figure 1 to locate electrostatic discharge (ESD) immunity to the corresponding fault part:

2 KV ESD for oscillator unit

l PLL battery cell for 3 KV ESD

The next post will follow with "ESD Problem Response".

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