With the high-frequency and Digitalization of electronic devices, how to achieve more efficient noise suppression within a limited space has become a major challenge for modern engineers. This places higher demands on the EMI characteristics and noise reduction capabilities of MLCC (Multilayered Ceramic Capacitors with three terminals). The three-terminal MLCC (three-terminal multilayered ceramic capacitor) is breaking through the traditional filtering bottleneck through structural innovation and providing an optimal solution for engineers in the era of high-density electronics.

Figure 1: Circuit Layout Optimization Diagram

Structural differences

1. Ordinary MLCC

Figure 2: Conceptual diagram of the internal structure of a common MLCC

Structure: Composed of alternating layers of ceramic dielectric and metal electrodes, with only two external ends. The current path must pass through the entire capacitor body.

Parasitic parameters: The equivalent series inductance (ESL) is relatively high because the current path is quite long (it needs to flow in from one end and out from the other end).

2. Three-terminal MLCC

Figure 3: Conceptual diagram of the internal structure of the three-terminal component

Structure: On the basis of the ordinary MLCC, an additional third terminal (usually the grounding terminal) is added. The internal electrodes are designed as a "dual electrode layer" structure, with one side of the electrodes directly connected to the third terminal.

Parasitic parameter optimization: The current path is shortened (input → electrode → ground terminal), significantly reducing ESL (typically 50% or more lower than that of ordinary MLCC).

Differences in working principles

1. Ordinary MLCC

Function: Primarily serves as an energy storage, filtering, or bypass capacitor, smoothing out voltage fluctuations through charging and discharging.

Equivalent circuit: Simplified to a capacitor (C) in series with an equivalent series inductance (ESL) and an equivalent series resistance (ESR). At high frequencies, ESL significantly affects performance (impedance increases with increasing frequency).

2. Three-terminal MLCC

Function: Through the third terminal (ground), a low-impedance circuit is formed, allowing high-frequency noise to bypass directly to the ground instead of flowing through the entire capacitor body.

Equivalent circuit: It can be regarded as two parallel capacitors, "input-ground" and "output-ground", forming a structure similar to a π-type filter, with lower high-frequency impedance.

Application scenario differences

The three-terminal MLCC significantly reduces ESL through structural optimization and is specifically designed for high-frequency noise suppression. While ordinary MLCC cover most basic scenarios with their versatility and low cost. When designing high-frequency/high-speed systems, the three-terminal MLCC is a key component for enhancing signal integrity and EMC performance.

EYANG Technology has been dedicated to the research, production and sales of chip-type Multilayered ceramic capacitors (MLCC). As one of the leading enterprises in the MLCC field in China, EYANG Technology is committed to providing small-sized, high-performance and highly reliable electronic component solutions for the global electronics industry. It has cooperated with many leading enterprises in various industries such as consumer electronics, semiconductor packaging and testing, industrial control, communication equipment, artificial intelligence, and automotive electronics. We will create value for our customers through continuous technological innovation and service advantages!