Complete ESD and EMI protection solution

Another category is products using PicoGuard® XS technology. This type of design uses an impedance matching circuit to ensure an impedance of 100 Ω, which is equivalent to zero capacitance. This type of design does not require a parallel inductor, which helps minimize ESD voltage spikes caused by the package.



Figure 4: Comparison of traditional methods and PicoGuard® XS design methods

ON Semiconductor's protection and filtering solutions are based on traditional silicon chip process technology. In contrast, other types of low-cost passive solutions use materials such as ceramics, ferrites, and multilayer varistors (MLVs). Such devices generally have poor ESD clamping performance. In some cases, the energy delivered to downstream devices may be an order of magnitude lower than that of ON Semiconductor solutions. Some products using older technology may even degrade and become worse after a small amount of ESD strikes. Due to the nature of their materials, some passive components tend to show temperature inconsistencies, which reduces the reliability of the end system operating within the standard consumer temperature and ambient temperature range.

Other characteristics must be considered .

ESD and EMI solutions prevent unwanted signals from interfering with the overall performance of the system. During normal system operation, the protection device must also maintain good signal integrity for a given interface, in other words, it should be completely "transparent". ON Semiconductor's devices are suitable for operating and protecting today's most common consumer electronic system interfaces. Typically, the impact of signal integrity is measured using S-parameter insertion loss curves, and filter solutions can also measure the response of the filter. Eye diagrams can also be used to measure signal integrity (especially for high-speed devices) to prove the maximum data rate that can be achieved by the device during normal operation without interference.

ON Semiconductor has two basic types of EMI filters. The first type is a single-ended low-pass filter in various array configurations for parallel interfaces; it is divided into traditional and general-purpose resistor-capacitor (RC) versions, and inductor-capacitor (LC) versions for high-speed and power-sensitive interfaces.



Figure 5: Single-ended low-pass filter characteristics

According to the specifications, each component has a passband range. These devices can cut off high frequencies ranging from 700 MHz to 6 GHz.

The second type of EMI filter is suitable for high-speed serial interfaces and has the function of exceeding the typical low-pass filter. This type of interface is a differential signal path with inherent noise suppression, but it will not be completely immune to common-mode noise from external sources or block interface signals from radiating to other parts of the system.



Figure 6: Common Mode Filter (CMF) Characteristics

Protected common mode filters (pCMF) can be used to eliminate unwanted common mode noise and prevent radiated harmful common mode noise signals from entering other parts of the system from high-speed interfaces. At the same time, it can also make high-speed data channels almost undisturbed.

In addition to ESD strike protection, ON Semiconductor also provides solutions to protect against surge strikes caused by lightning strikes or power cross faults. A common interface in various consumer electronics and telecommunications/networking equipment is the RJ45 interface that complies with the 10/100BASE-T and 1000BASE-T Ethernet protocols, and its surge rating is often the indoor standard. These interfaces consist of four pairs of differential data lines, each of which can transmit data rates of up to 250 Mbps. Protection for such interfaces needs to ensure that lateral (metallic) surge strikes do not damage sensitive downstream chips (such as the physical layer). This is achieved by connecting shunt protection elements to the line-to-line (each pair of lines) to divert the incoming surge energy.

For lower data rate (10/100BASE-T) applications, ON Semiconductor offers a combination of crowbar devices called TSPDs (thyristor surge protection devices), and clamping devices for similar ESD protection. TSPDs offer the advantage of low clamping voltages with higher surge current capabilities. For example, these devices can meet the requirements of the GR-1089 10/1000 μs standard and are therefore suitable for primary or secondary side protection, also known as “line end” protection. TVS (transient suppression diode) clamping devices support surge levels of 8/20 μs pulses and are typically used on the tertiary or PHY side to capture and safely eliminate any residual surge pulses.

Typical circuit protection application examples

Smartphone applications are a typical protection application. ON Semiconductor's solutions include data filters, ESD protection diodes and arrays, and voltage protection devices. USB2.0 protection for consumer and portable applications includes high-speed pairs, VCC, and low-capacitance ESD protection; USB 3.0 has two super-speed pairs and one high-speed pair, as well as VCC and low-capacitance ESD protection. The eSATA interface has two high-speed pairs and low-capacitance ESD protection.



Figure 7: Smartphone block diagram and I/O interfaces that need protection (see the light blue background area on the lower right)

For parallel interfaces of 4 to 12 lines for cameras and displays, ON Semiconductor has low-pass LC filters + ESD protection devices, as well as common-mode filters + ESD protection for 3 to 5 high-speed serial channels. For portable HDMI, consumer HDMI/display ports, four high-speed pairs, up to 6 additional interface lines, and low-capacitance ESD + common-mode filter solutions can be used.

In addition, ON Semiconductor's protection applications also include audio (speakers/headphones), SD interfaces, SIM cards, keyboard EMI suppression, Ethernet, and T1/E1, T3/E3 and xDSL ports, etc., which can meet the higher requirements of consumer electronic products for strong ESD protection and EMI/RFI noise reduction.

Powerful ESD protection and EMI filtering product lineup for portable and consumer application interfaces

ON Semiconductor, as the world's leading silicon solution supplier for energy-efficient electronic products, ranks first in the circuit protection market and provides a wide range of ESD protection and EMI/RFI filtering products for portable and wireless, consumer, computer and peripherals, automotive and telecommunications markets. Table 1 and Table 2 list ON Semiconductor's ESD protection and EMI filtering solutions for portable application interfaces and consumer application interfaces, respectively. Customers can choose the appropriate solution according to actual application requirements.



Table 1: ON Semiconductor Portable Application Interface ESD Protection and EMI Filtering Solutions



Table 2: ON Semiconductor Consumer Application Interface ESD Protection and EMI Filtering Solutions

Summary:

ON Semiconductor is a global leader in circuit protection. Its leading ESD protection products include: the traditional ESD protection solution with the lowest capacitance and extremely low clamping voltage in the industry; the first PicoGuard XS protection solution on the market that is equivalent to providing zero capacitance; and the common mode filter solution with integrated ESD protection, which is also the first on the market. These highly integrated protection solutions help customers protect the increasingly high-speed sensitive chipsets in their products and reduce the space occupied by circuit boards.