network and systems laboratory nslab.ee.ntu.edu.tw zzz 2011/12/16wireless sensor network and labs...

Network and Systems Laboratorynslab.ee.ntu.edu.tw

zzz

2011/12/16Wireless Sensor Network And Labs fall 2011 1


Today’s ClassLast week

IntroductionCreate schematic libraryCapture schematic

Create PCB library (footprint)Layout



Through-hole PackagesSIP: single in-line packages

DIP: dual in-line packages

Through-hole package are old, their number decreased in modern design



SMD PackagesChip resistors, capacitors, inductors

0402, 0603, 0805, … Represent size of the chip 0805 means 0.08” x 0.05” rectangle



SMD Packages SO: Small outline

Usually refer to IC with two rows of leads

QFP: Quad flat package



SMD Packages QFN: Quad flat package, no-leads

The packages we introduced just now are most commonly usedDevice datasheet should include the package

informationYou will need it for PCB layout



SMD Packages BGA: Ball Grid Array

PGA: Pin Grid Array

These two are widely used in high end processor. They allow more pin-out from a single package. We seldom use ICs in these package, it is too difficult to solder by hand



Why To BuyVarious sources

Online retailers www.digikey.com www.mouser.com

Local distributorsThese are probably two of the world largest online electronic

components retailers. If the component you need cannot buy

from these two sources, you might want to consider the other

component!



Block Diagram

TarokoLocation node

TarokoControl node

Battery4 AA

6V output

Regulator

LM317L

Connector

3-PinInfrared

Connector

3-PinInfrared

Connector

3-PinMotor

Connector

3-PinMotor

3.3V

3.3V

6V

6V



ComponentsBattery connector: 2-pin, Regulator: LM317L, 8-pin SOIC

Resistor, capacitorTaroko connector

Location node: 2x5 pin, 2x3 pin Control node: 2x5 pin, 2x3 pin

Infrared connector: 3 pin Motor connector: 3 pin



PCB LayoutSoftware

We are using “Altium Design 6”There are many other software available

Process1.Initial setup2.Create schematic library3.Capture schematic4.Create PCB library5.PCB layout6.Output



PCBcopper

copper

copper

1-layer board

2-layer board

Multi-layer board(Taroko is 4-layer board)



TerminologiesTop layer: copper on top

Top overlay: white marks on top layer

Bottom layer: copper on bottomBottom overlay: white marks on Bottom layer

Keep out layer: defines the shape of the board

pads: holds the IC leads

vias: holes


Top paste: paste mask on top layerTop solder: solder mask on top layer

Bottom paste: paste mask on Bottom layerBottom solder: solder mask on Bottom layer


PCB LibraryOnce you have every component you need on

the schematic library, you can start create PCB library

PCB library defines the footprint of the component


AD7798AD7798 LM317L

LM317L


What Is Footprint

A footprint created in the software

After finish the layout and get the PCB board. This is how it look like.

AD7798 placed on the board



Dimension

Must follow the exact dimension Other wise the component cannot solder on the board

Leave some extra space for soldering

6.4mm

extra space for soldering

The basic idea is the footprint you defined can fits the chip

The basic idea is the footprint you defined can fits the chip



Simple Calculation4mm

7.7mm

These are pads, they use to hold the lead of the IC. You can define the length you want. You must leave some space for soldering

These are pads, they use to hold the lead of the IC. You can define the length you want. You must leave some space for soldering

(0.3* 1.85) mm



The Footprint You NeedLM317L Regurator

SOIC 8 (Check datasheet)Power Connector (端子台 )

Pitch 5.08mmInfrared proximity connector

Pitch 2.0 mmConnector: 2x5 pin, 2x3 pin, 3 pin

Pitch 2.54mmChip capacitor, resistor

0805



LM317L Physical Dimension



Create Footprint – By WizardBy wizard (old version altium)Tool -> IPC Footprint Wizard



Step 1



Step 2


Check datasheet for

correct number


Step 3 – No Need Thermal Pad



Step 4 – Use Default



Step 5 – Low Density


You can use large Toe Fillet, hand soldering will be easier

You can use large Toe Fillet, hand soldering will be easier


Use Default



Step 7 – Use Default



Give It A Name



SOIC-8 Footprint



X,Y Coordinate

1 4

58

(0,0)

(1.27,0)

(0,5.2)


(2.54,0)

(3.81,0)


Create FootprintManual edit

Place padsPlace overlay

The white mark



Power ConnectorCreate Footprint



Infrared Connector


millimetersmillimeters


Copy Footprint Copy miscellaneous component’s footprints

In you are using Win 7 Copy “Miscellaneous Connectors.IntLib” and

“Miscellaneous Devices.IntLib” to another directory In C:\Program Files\Altium Designer 6\Library

Open and extract these two libraryCopy following footprint

Miscellaneous Devices.PcbLib 2012[0805]

Miscellaneous Connectors.PcbLib HDR1x2, HDR1x3, HDR2x3, HDR2x5



The Footprint You NeedLM317L Regurator

SOIC 8 (Check datasheet) Create by wizard

Power Connector (端子台 ) Pitch 5.08mm Manual create

Infrared proximity connector Pitch 2.0 mm Manual create

Connector: 2x5 pin, 2x3 pin, 3 pin Pitch 2.54mm Copy from miscellaneous component’s footprints

Chip capacitor, resistor 0805 Copy from miscellaneous component’s footprints



Link Schematic Library And PCB LibraryAfter create all the footprint need, linking

with the schematic librarylink schematic library and PCB library Update schematic

NotesPins on the schematic library must map to the

pins on PCB library, which is identical to real chip.



Pin To Pin Mapping



Check Schematic And Choose FootprintChoose Footprint



Normal Procedure


1. Create component libraries in the PCB software

Schematic library PCB library Link PCB and Schematic

library2. Capture schematic

Draw the circuit on the PCB software

Choose footprint when you place components

3. Layout1. Decide the shape of the board2. Placing components3. Make connections

4. Make the hardware board Export layout to manufacturer

output, send to PCB manufacturer

Home made PCB

1. Create component libraries in the PCB software

Schematic library2. Capture schematic

Draw the circuit on the PCB software

3. Create PCB library Link PCB and Schematic

library Update schematic Choose footprint

4. Layout1. Decide the shape of the

board2. Placing components3. Make connections

5. Make the hardware board Export layout to

manufacturer output, send to PCB manufacturer

Home made PCB

Procedure we took

Procedure we took

Normal procedure

Normal procedure

Is better to follow this one


NowCreate your footprintChoose correct footprintCheck schematic



Export to PCBCompile the schematic and export the

components to PCB design documentCompile

Project -> Compile Document xxxxx.SchDocExport the footprints to PCB

Design -> Update PCB Document xxxxx.PcbDoc



Environment And Keep-OutSetup the layout environment and defines the

keep out layerEnvironment (optional)

(Right click) Option -> Board Options Metric or Imperial Snap grid

Define Keep-out Define the shape of your PCB board



Component PlacingPlace the component 01 02

Component placing is importantCarefully place the component according to the

signal pathFrequency used quick key

Dragging the component, press “space” to rotate Dragging the component, press “l” to place at the

other sizePlace the bypass capacitor as close to the

power pin as possible



Design RulesEditing design rules

It defines the rules that your PCB board must follow

Frequently used rules Clearance – minimum distance between traces Routing Width – minimum and maximum allowable

trace width Routing Vias – minimum and maximum via size

(diameter and hold size)At least you need to change “routing width”



PCB LayoutRouting 01 02 03 04

My way Route the power line first, route them at the edge

Make the track width wider for power line Route the signal line on the top layer as much as

you can Make the bottom layer as a continuous ground

plane



Place Some SignatureJust for fun

You can put some text on the “Overlay layer” Either “Top Overlay” or “Bottom Overlay”

Text can be Team name Members name Date Whatever you want



Design Rules Check (DRC)This function check everything

According to the rules you setupRun Design Rules Check (DRC)

If errors found, must fix itClearance Constraint Broken-Net Constraint Fix errors and run DRC again



Ground (GND) Polygon PourPolygon Pour is a large area of copper

Usually use for GNDRoute signal on one side, place GND polygon

pour on the other sideConnect every GND through a via to another

sidePlace GND polygon pour

And run DRC again



Fabrication OutputsExport the layout to fabrication outputs

1. Export Gerber files2. Export NCdrill file3. Pack all files in project output directory

Send these files to PCB manufacturer wait for about 1.5 weeks cost about NT4000 ~ NT6000 you will get a professional PCB board



Send FilesSend me the whole project files

Whole project directoryOne layout for each teamBefore next Friday (12/23)

I will check the files and send to manufacturer by Wednesday



Will it work? We’ll see


network and systems laboratory nslab.ee.ntu.edu.tw zzz 2011/12/16wireless sensor network and labs...

Documents

wireless sensor network

systems laboratory

pin motor connector

2x5 pin

2x3 pin infrared connector

pin grid array

2x3 pin control node

pin soic resistor