Hee-do Kang

A Localized Enhanced Power Plane Topology for Wideband Suppression of Simultaneous Switching Noise

Using a complementary spiral resonator mounted on the power plane, simultaneous switching noise and ground bouncing noise can be suppressed over a very wideband from 0.22 to 12.5 GHz under a noise suppression margin of -25 dB. Not only the suppression characteristic under 12.5 GHz is possible, but also over the higher frequency band, because the proposed structure operates like an RF choke. Therefore, the proposed structure can satisfy the 10% noise margin for the voltage swing ratio for both periodic and random clock signals. A size of 3.2 mm is necessary for the diameter of the resonator on the power plane, and is comparable to a clearance pad size with diameter of 3.0 mm in a ground plane. Hence, the small size helps to reduce the discontinuity of the return current path; therefore, signal integrity problems and the degrees of freedom for power plane design of an electromagnetic bandgap structure are enhanced. Moreover, the effects of inductance and capacitance in the spiral resonator are analyzed for modeling. As a result, the suppression bandwidth and resonance frequency are controlled by the arm length and gap of spiral resonator. In addition, by applying two different sizes of resonators, it is shown that a multiresonance effect is also obtained.

Signal Integrity Enhanced EBG Structure With a Ground Reinforced Trace

In general, a conventional electromagnetic bandgap (EBG) structure efficiently suppresses simultaneous switching noise (SSN) over a wide frequency range. However, it is difficult to apply the geometry to the design of a real printed circuit boards (PCBs) for high-speed digital circuits due to the degradation in the signal integrity performance. In this paper, a ground reinforced trace (GRT) is added to the EBG power plane to guarantee power integrity (PI) as well as signal integrity (SI) simultaneously. In addition, the definition of a noise suppression bandwidth in an EBG structure is derived for the purpose of analyzing the correlation between the GRT and the noise suppression bandwidth. This correlation is utilized to decide the location of the GRT to mitigate the degradation of the low-pass cutoff frequency. As a result, an excellent signal performance is achieved without any degradation of the noise suppression bandwidth in a conventional EBG structure.

Electromagnetic Modeling of High Altitude Electromagnetic Pulse Coupling into Large-Scale Underground Multilayer Structures

This paper gives a electromagnetic coupling mechanism of the high altitude electromagnetic pulse (HEMP) into large- scale underground multilayer structures using analytic and numerical methods. The modeling methods are firstly addressed to the HEMP source which can be generated by intentional nuclear explosion. The instantaneous and intense electromagnetic pulse of the HEMP source is concerned from DC to 100 MHz band, because the power spectrum of the HEMP is rapidly decreased under -30 dB over the 100 MHz band. Through this range, a penetrated electric field distribution is computed within the large-scale underground multilayer structures. As a result, the penetrated electric field intensities at 0.1 and 1 MHz are about 10 and 5 kV/m, respectively. Therefore, additional shielding techniques are introduced to protect buried structures within the large-scale underground structures such as high-lossy material and filtering structures (wire screen).

Power noise suppression techniques using spiral resonator in high-speed PCB

In this paper, to the aim of more than 10 dB power noise suppression, investigation of spiral resonators applied in the vicinity of the practical high-speed digital circuit. Their performances are characterized in terms of their capability to effectively suppress simultaneous switching noise in the frequency region of interest with small occupying area on the power distribution network. As a starting point, the maximum order of harmonic up to which the most energy of clock signal is concentrated is estimated by power spectrum analysis for practical high-speed digital circuit. Then, design parameters of a spiral resonator such as the width, the gap and the number of turns were simulated to determine the suppression level and bandwitdh in DDR3 signal. Numerical results are given in order to illustrate the effectiveness of noise suppression of spiral resonator and to validate the theoretical analysis.

A Noise Suppression Technique Using Dual Layer Spirals with Various Ground Structure for High-Speed Pcbs

In this paper, small dual layer spirals with several various ground structure are applied in the vicinity of the DDR3 high-speed circuit to achieve noise suppression characteristics up to 3.2GHz region. For wider noise suppression bandwidth, the dual layer spirals with various ground structure, which provide high self resonance frequency (SRF) as well as inductance value, are implemented. The proposed dual layer spiral with various ground clearance dimension exhibits greater than 9dB power noise suppression characteristics in the frequency range of interests and achieve about 50% voltage ∞uctuation reduction in time domain compare to the reference case model. To validate the efiectiveness of the proposed model, sample PCB are fabricated and measured. It shows good agreement between the measured and simulated results up to 3.2GHz.

An enhanced power plane topology using localized spiral resonator for wideband suppression of simultaneous switching noise

Using power plane applied spiral resonators, GBN and SSN can be suppressed through very wideband from 0.22 GHz to 12.5 GHz under −25 dB. Also, the designed spiral resonator is just located on the intersection between power plane and power via, and the diameter of resonator is 3 mm. Due to the localized small size of resonator, the degree of freedom for power plane design and signal integrity for guaranteed return current path are better than periodic EBG structure. Therefore, signal integrity and power integrity can be guaranteed in a low noise condition by using spiral resonator mounted power plane.

Analysis of signal integrity/power integrity in multilayer printed circuit board and two improving methods

The signal integrity (SI) and power integrity (PI) in multilayer printed circuit board is analyzed using three-dimensional (3D) full EM simulation and the circuit simulation. As a result of that, the dominant factor of SI/PI on the test board is noise coupling by GND via. Hence, two methods are applied to suppress the coupling; differential signaling and anti-via structure. Using these two methods, the noise on the signal line and power via can be suppressed, remarkably. Therefore, the SI/PI in multilayer PCB can be guaranteed to the low noise level.

Power Noise Suppression Methods Using Bead with Spiral Resonator

In this paper, to the aim of wideband SSN(Simultaneous Switching Noise) suppression characteristic, investigation of spiral resonator are used in conjunction with bead which is commonly used for noise suppression method. Bead works effectively to suppress the power noise up to the first harmonic of fundamental frequency, 0.8 GHz, and spiral resonator suppress noise well in the frequency range of SRF(Self Resonance Frequency) which is inversely proportional to the length of spiral. Thus, when bead used in conjunction with a spiral the noise suppression characteristic is determined by the one of higher impedance element of the two in the frequency range and achieves more broadband filtering characteristic. The case for using 22 nH bead turns out 4.8, 2.0, 0, and, 0.6 dB, and the case for using 22 nH bead in conjunction with 3-turns spiral achieves more wideband characteristic of 9.5, 8.3, 6.1, and 9.9 dB power noise suppression performances at the first, second, third, and fourth harmonics, respectively. The peak-to-peak voltage levels decrease from 76 mV to 56 mV using 22 nH bead, and the level decrease rapidly to 34 mV when using in conjunction with bead and 3-turn spiral. Thus more wideband SSN suppression characteristic can be achieved using bead with spiral.

Modeling and analysis of electromagnetic bandgap structures on power distribution network

Transmission line method (TLM) is applied for analysis of a conventional electromagnetic bandgap (EBG) structure with arbitrary shaped power/ground plane. The fast and accurate modeling by TLM shows the computationally efficient results with respect to full-wave electromagnetic analysis. More-over it is shown that suppression bandwidth of a EBG structure can be easily analyzed by stepped impedance filter and the calculated bandwidth is identical to the measured.

Optimization of via structure in multilayer PCB for high speed signal transmission

44-layers PCB (printed circuit board) for semiconductor test has been analyzed and optimized to improve the transmission performance. By dividing the PCB to subsections and analyzing each section, stub resonance reported in [1] brings the degeneration of transmission performance.