Analysis and Simulation of Time-domain Waveforms of a Photoflash Circuit
Date Issued
2007
Date
2007
Author(s)
Ou, Tsung-Han
DOI
en-US
Abstract
The main purpose of this thesis is to develop tools to predict the key behaviors of a commonly used photoflash circuit. Two levels of accuracy are targeted. In the first level, a simplified equivalent circuit was obtained. Relatively crude component models were used and analytical results can be obtained from the simplified equivalent circuit. The other level of accuracy was targeted at higher accuracy. More elaborated component models including nonlinear capacitance effects of semiconductor junction, the parasitic capacitances of transformer and the parasitic resistances of print-circuit-board trace and MOSFET were used and IsSpice computer simulation was used to predict circuit behaviors. The modeling and analysis provide insight into the complex interaction between components parasitic elements and switches. Key information such as voltage spikes of power semiconductor switches and the charging time for the charger can be predicted.
Both the simulation results and the analytical results from the simplified circuit analysis were compared with experimental measurements. Reasonable agreements were obtained for most key waveforms. The tools developed enable designers to investigate into the physical circuit behaviors and obtained practically useful design information.
Subjects
閃光燈
非線性電容
IsSpice電腦模擬
模型化
寄生元件
電壓突波
photoflash
nonlinear capacitance
IsSpice computer simulation
modeling
parasitic elements
voltage spike
Type
thesis