September 24-28, 2012 Carol Lenk Introduction to Prototyping a LED Driver Part II: Using PCB Layout Software – Schematic Capture and Component Libraries
Schematic Capture Using DesignSpark, freeware, good feature set, no limitations. New schematic. Add components. Add connection wires.
Add Component Select resistor.cml library. 0.1W resistor is SM0805 package. Will use 0.063W with SM0603 package and change the name. Only 150K available. Will change value. Need to copy component to our custom library and make changes there.
Custom Libraries Create custom library to store commonly used components and to modify components. Add path of New Library to Files tab.
Create New Library for Component: 9910Demo.cml Custom Libraries
On Component Tab, find resistor.cml, find “r 0.063w SMTF”, click Copy To…, navigate to our library, rename “R”. We’ll add the resistance for each instance of R on the schematic, so we can display it on the schematic. Copy Component
Add Component
Properties Double click on component to get to Properties. – Double click on the text to get “text” tab to control what is displayed.
Values Properties: Values Tab Double click on Value to change it. Click on Add.. To add Digikey field with part number.
Add Capacitor Copy capacitor to our library Go to Library Manager. Select capacitor.cml library. Select 1206 package. Copy component to our 9910Demo.cml library. Rename component as C. Add C to our schematic Go to Add Component. From our library, select C.
Add Values to C Double click on component to go to Properties. Go to Values tab. – Double click on Mfr, delete AVX. – Click on Add, type “Value” for Name and “10 uF, 35V” for Value. – Click on Add, type “Digikey” for Name and “ ND” for Value. – Check box for value to display capacitance. Double click on component label to adjust display. – In Text tab, uncheck “Component Name.”
Connect Components Double click on x on R1, double click on x on C1. Hover cursor over wire to see the name of the connection net. Right click on wire to change net name.
Translate to PCB In Tool Menu, select Translate to PCB. New PCB Wizard – use default settings. – Units, 2 Layer Board, board size, etc. 9910Demo.pcb – Footprints – Yellow is Silkscreen – Green is board outline – Airwires show pads that should be connected.
Lay Down Copper Move components to within board outline. Double click on pad to start wire, double click on destination pad to finish wire.
Thank You