Research On Power Integrity And Signal Integrity In System In Packaged Transmission Channel For Power Device

The integration of circuits and their high densities,coupled with the ever-growing capabilities of electronic products,are being advanced by science and technology.However,at present,the size of electronic devices is getting smaller and smaller.The change rate of RF power amplifiers will become higher and higher along the direction of the pin signal,resulting in an urgent need to solve the problem of signal integrity of power devices.In addition,with the continuous increase of working frequency and the decrease of working voltage,the problem of power integrity caused by synchronous switching noise is becoming more and more serious.Therefore,this paper takes the transmission channel of the RF power amplifier in the system in packaged design as the research object,systematically and deeply studies the influence of the change of package structure parameters on its signal integrity,combined with the analysis of the influence of the position of BGA tin ball on power integrity.The optimized transmission channel and the optimized BGA tin ball layout complement each other to improve the overall power and signal integrity.The specific research contents are as follows:(1)In order to study the signal integrity under the condition of high frequency,the system in packaged design of RF power amplifier is carried out in this paper.A simplified simulation model of an RF power amplifier is established by using a three-stage cascade circuit structure.The model’s transmission channel of a pair of differential lines is imported into ANSYS Q3 D simulation software to analyze the relationship between parasitic RLGC parameters and frequency.In the fourth chapter,the signal working frequency is determined as 5GHz,which analyzes the influence of signal frequency on signal integrity parameters such as signal loss and signal crosstalk according to the finite element model.(2)Based on the ANSYS SIwave three-dimensional electromagnetic simulation model,this paper explores the effects of via structure,transmission line and BGA tin ball on insertion loss and echo loss.The correctness of simulation results is verified by experiments,and the optimal parameter combinations of insertion loss and echo loss of transmission channel are obtained by using the response surface and orthogonal design method.The influencing factors of insertion loss range analysis are as follows: transmission line width >through-hole pad radius > through-hole radius > BGA ball middle radial radius;the order of influencing factors of echo loss range is as follows: transmission line width > through-hole radius > BGA ball middle radial radius > through-hole pad radius.The analysis of variance shows that the transmission line width has a significant effect on the insertion loss and echo loss of the transmission channel,while the through-hole pad radius,through-hole radius and middle radial radius of the BGA tin ball have no significant effect on the insertion loss and echo loss of the transmission channel.The insertion loss and echo loss of the transmission channel structure optimized by the response surface method are improved.(3)Based on the ANSYS SIwave three-dimensional electromagnetic simulation model,this paper explores the influence of through-hole structure,transmission line and BGA tin ball on signal crosstalk,and uses grey correlation and orthogonal design to obtain the optimal parameter combination of near-end crosstalk and far-end crosstalk of transmission channel to meet the design requirements.The order of influencing factors of the near-end crosstalk range is as follows: transmission line width > BGA tin ball middle radial radius > throughhole pad radius > through-hole radius;the order of influencing factors of far-end crosstalk range is as follows: through-hole pad radius > transmission line width > through-hole radius >BGA ball middle radial radius.The analysis of variance shows that the transmission line width has a significant effect on the near-end crosstalk of the transfer channel,the transmission line width has no significant effect on the far-end crosstalk of the transfer channel,and the through-hole pad radius,through-hole radius and the middle radial radius of the BGA tin ball have no significant effects on the proximal and distal crosstalk of the transfer channel.The signal crosstalk of the transmission channel structure optimized by the grey correlation method is improved to a certain extent.(4)Based on the collaborative modeling of the die and substrate,the ANSYS SIwave software is used to analyze the power supply tin ball and grounding tin ball packaged by BGA.By adopting the arrangement and combination of several tin balls and a pair of tin balls,the different impedance curves of the observation points are obtained,and the placement rule of the lowest loop inductance is found,so as to improve the integrity of the power supply.In conclusion,this paper preliminarily explores the power supply and signal integrity of RF power amplifiers,which provides a certain theoretical value and practical significance for the transmission channel in system packaging and practical application of power devices.