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PCB Design. Practical Design Guidelines http://sercpitt.weebly.com/. Preliminary Design Questions. Important Datasheet Info. Pinout and Pin Orientation Package Size and Type Power Rating Soldering Temperatures Recommended Configurations. Protection Devices. Voltage Arresters. Fuses.
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PCB Design Practical Design Guidelines http://sercpitt.weebly.com/
Important Datasheet Info Pinout and Pin Orientation Package Size and Type Power Rating Soldering Temperatures Recommended Configurations
Protection Devices Voltage Arresters Fuses ESD Protection Mechanical Protection EMI Protection Reverse Bias Protection
Power Generation • Switching Converters • Linear Regulators
Key Principles How current flows through the board and its return pathway to ground with changes in frequency. Traces can cause unwanted inductance or capacitance depending on how they are laid out. Electric and magnetic field coupling and its propagation around traces and planes and how these fields couple into surrounding traces/planes. Amount of current and voltage that is on traces and how that changes the propagation of the EM fields from the trace or how the trace is affected by outside radiation. The smaller the signal on the trace the more susceptible to outside radiation it is. While a high current or very large signal can cause very large EM wave propagation that creates noise on surrounding ground planes and traces.
Coupling • Inductive • Capacitive
PCB Stackup Goals A signal layer should always be adjacent to a ground or power plane. This means placing the ground or power plane one layer below or on the same layer as the trace is being run. This allows for return current to be as close to the source as possible. Signal layers should be tightly coupled to their adjacent planes. This means keeping the ground plane close to the signal plane either above or below. Power and Ground planes should always be closely coupled together. This means placing the planes within one or two layers of each other. High speed signals (>500MHz) should be routed on buried layers located between planes. In this way the planes can act as shields and contain the radiation from the high speed traces. Multiple ground planes are very advantageous, since they will lower the ground (reference plane) impedance of the board and reduce common mode radiation.
Component Selection Resistors Capacitors Inductors IC’s: Surface Mount vs. Through Hole
Layout Programs ExpressPCBIntro Tutorial: http://home.wlu.edu/~ericksonj/engn208_w2015/hw/expressPCBtutorial.pdf Eagle Intro Schematic Tutorial: https://learn.sparkfun.com/tutorials/using-eagle-schematic Eagle Intro PCB Tutorial: https://learn.sparkfun.com/tutorials/using-eagle-board-layout AltiumIntro Tutorial: http://techdocs.altium.com/display/ADOH/Tutorial+-+Getting+Started+with+PCB+Design# Mentor Graphics Pad Intro Tutorial: https://engineering.purdue.edu/ece477/Archive/2011/Spring/S11-Grp07/nb/datasheets/pads_tutorial_2_rev.pdf
PCB Ordering Manufactures Components Digikey: https://www.digikey.com/ Mouser: http://www.mouser.com/ Jameco: http://www.jameco.com/ Sparkfun: https://www.sparkfun.com/ Adafruit: https://www.adafruit.com/ Arrow: https://www.arrow.com/ • Sunstone: http://www.sunstone.com/ • Advanced Circuits: http://www.4pcb.com/ • ExpressPCB: https://www.expresspcb.com/