Seminar on“Circuit Simulation and PCB Design

using OrCAD”Prof. Anish Goel

Contents� Basics of Circuits and Components� Concepts of Printed Circuit Boards (PCB’s)� Electronic System Design Flow� Introduction to PSPICE model� Schematic Design� Schematic Design� PSPICE simulation� PCB design using OrCAD� Testing design� Workshop on OrCAD

2 OrCAD of Cir. Sim. and PCB Design ANISH GOEL

Basics of Circuits and Components

� What is a circuit?� Any system that is formed by interconnecting electronic components.

� A system that processes electronic data.� Circuits maybe classified as Analog circuits or digital circuits.� Mixed signal circuit is also possible.� Mixed signal circuit is also possible.

3 OrCAD of Cir. Sim. and PCB Design ANISH GOEL

Basics of Circuits and Components Cont…

� What is Component?� Any discrete electronic device that understands electronic Signals.

� Electronic Components are generally made up of metals and semiconductors

� Smaller components may be integrated together to build larger � Smaller components may be integrated together to build larger components.

4 OrCAD of Cir. Sim. and PCB Design ANISH GOEL

Printed Circuit Boards� PCB is a platform that is used to place and connect all the components together.

� The board is made out of a insulator/substrate.� Components are placed in the holes of the PCB.� The leads of the components are connected using copper � The leads of the components are connected using copper tracks.

� Printed circuit boards are classified into following:� Single sided PCB (Components on one side and tracks on other side)

� Double sided PCB (Components on one side and tracks on both sides)

5 OrCAD of Cir. Sim. and PCB Design ANISH GOEL

Types of PCB’sSingle Sided PCB and Double Sided PCB

6 OrCAD of Cir. Sim. and PCB Design ANISH GOEL

Electronic System Design Flow

Schematic Design

Circuit Simulation

PCB design

Testing and Verification

7 OrCAD of Cir. Sim. and PCB Design ANISH GOEL

Introduction to PSPICE model

� SPICE: Simulation Program with Integrated Circuit Emphasis.

� PSPICE: Programmable SPICE� It is computer program that help in modeling components and simulating their functionality.

� A SPICE model is a text-description of a circuitcomponent used by the SPICE Simulator tomathematically predict the behavior of that part undervarying conditions.

8 OrCAD of Cir. Sim. and PCB Design ANISH GOEL

PSPICE model Cont… Transistor Parameters

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Schematic Design

� First step for building a electronic circuit/system.� Schematic is a standard way representation of circuit.� It can be understood by any circuit designer.� It can be modified as per the requirements.� Schematic is used by SPICE for circuit simulation.� Schematic is used by SPICE for circuit simulation.� Same schematic maybe used to design PCB.

V1

FREQ = 50VAMPL = 5VOFF = 0 R1

{rv ar}

0

1 2D2

1N4376

10 OrCAD of Cir. Sim. and PCB Design ANISH GOEL

Complex Schematic Design

RTCK

L4L5L6L7L8 L1L2L3

sw2sw1

SDA_MEM

MOSI0

13579

1113151719

2468101214161820

J1

CONNECTOR EDGE 10x2

P1.1616

P1.1712

P1.188

P1.194

P1.2048

P1.2144

P1.2240

P1.2336

P1.2432

P1.2528

P1.26/RTCK24

P1.27/TDO64

P1.28/TDI60

P1.29/TCK56

P1.30/TMS52

P1.31/TRST20

RCTX135

P0.0/TXD019

P0.1/RXD021

P0.2/SCL022

P0.3/SDA026

P0.4/SCK027

P0.5/MISO029

P0.6/MOSI030

P0.7/SSEL031

P0.8/TXD133

P0.9/RXD134

P0.10/RTS135

P0.11/SCL137

P0.1238

P0.1339

P0.14/SDA141

P0.1545

P0.164647

U1

LPC2148 D

SCL_MEM

MISO0

AD1.5

0

C1

CAP

C2

CAP

C3

CAP

C4

CAP

A01

A12

A23

GND

4

SDA5

SCL6

WP7

VCC

8U3

AT24C01A

GND

15

VCC16

R1IN13

R2IN8

T2IN10

T1IN11

C1+1

C1-3

C2+4

C2-5

R1OUT12

R2OUT9

T1OUT14

T2OUT7

V+2

V-6

U2

MAX3232

0

SCK0

0

TXD0

594837261

P1

CONNECTOR DB9

594837261

P2

CONNECTOR DB9

R/W

VCC

RXD0

00

AD1.3

TCK

0

0

TRST

ENEN

0

TDI

0

AD1.4

VCC

TMS

D1

LED

D2

LED

D3

LED

VCC

TMSTRST

RTCKTDOTDITCK

D4

LED

D5

LED

D6

LED

D7

LED

VCC

D8

LED

TXD0

TDO

RXD0

LPC2148 D.K.

1 4

2 3

SW8RST_ISP

VCC

0

TXD1RS

RXD1

SDA_MEM

L4L1 L8L5L2 L6L3 L7

123456

J10

Analog I/P

R/W

AD1.0

1234

J5

I2C

C11

100N

TXD1

AD1.3

L3L2L1

L8L7L6L5L4

RXD1

R6

10K 0

R7

10K

VCC

R8

10K

0

VCC

sw[1:6]

AD1.4

R9

10K

VCC_BAR

123456

J6

SPI0

SCL_MEM

AD1.5

12

J2

HEADER 2

0SDA_MEM

123456789

R131K

R4

2K

AD1.7

R23RESISTOR

12345678910111213141516

J3HEADER 16

R5

2K

VCC_BAR

VCC

R12

10K

VCC

AD0.7

J8

VCC_BAR

SSEL0

OrCAD of Cir. Sim. and PCB Design ANISH GOEL11

VCC

CS2

Din3

VSS14

VDD5

CLK/SCLK6

VSS27

Dout8

NC9

DET110

NC1

DET211

U5

MMC/SD

sw6sw5sw4sw3sw2

0

RCTX1RCTX2

5

VDD323

VDD343

VDD351

VSS16

VSS218

VSS325

VSS442

VSS550

VREF63

VDDa7

VSSA59

P0.16P0.17/SCK1

47

P0.18/MISO153

P0.19/MOSI154

P0.20/SSEL155

P0.211

P0.222

P0.2358

P0.259

USBD+10

USBD-11

P0.2813

P0.2914

P0.3015

P0.31/USBled17

X162

X261

RST57

VBAT49

R151.5K

C1610u

1 234567

R18

10K

Y2

32768

0

C7

39P

C8

39P

0

R24

RESISTOR

VCC

R21

30k

0

0

VCC

VCC

VCC

0

0

123456

J4

HEADER 6

C9

20P

R22RESISTOR

VCC

R17

10K

R1

10K

C10

20PR2

33

1 4

2 3

SW2SWTCH1

0

R333

SSEL0

1 4

2 3

SW3SWTCH2

C2047U

0

1 4

2 3

SW4SWTCH3

sw1

VCC

0

C19CAP

12J9

VREF

123

J11supply

0

1 4

2 3

SW5SWTCH4

0

L1470uH

C15

100n

12

J12

HEADER 2

1 4

2 3

SW6SWTCH5

1 4

2 3

SW1

rst

sw2

0

1

J13

HEADER 1

R271k

IN4

OUT5

GND

3

ADJ1

ON/OFF2

U4

LM2941/TO220

1 4

2 3

SW7SWTCH6

VCC_BAR

0

D9LED

sw3

0

AD1.7

1

J14

HEADER 1

VCC

1

J15

HEADER 1

VCC0

Prof. Anish Goel

D10

BAT54C/SOT

1

J16

HEADER 1

0

R2510K

sw4

D11PW_LED

R2610K

0

12

J7

BAT BACKUP

C5

18P

1

32

Q2BC807

C6

18P

sw5

0 sw6

R16330

RS

0

0

R19RVOLT

0

0

1 2 3

456

SW9ON/OFF

R20RVOLT

R10

10K

0VCC_BAR

VCC

R14

2K

R11

10K

0

AD0.7

C12

100N

C13

100N

Y112MHz

MOSI0

C14

100N

AD1.0

C17CAP NP

C21100u

SCK0

VCC

MISO0

12

J8

BDG_E

PSPICE simulation

� This can perform :� Transient analysis.� Frequency analysis.� Simulation at different temperatures.

12 OrCAD of Cir. Sim. and PCB Design ANISH GOEL

PCB design using OrCAD

� No requirement for designing PCB separately.� PCB can be generated from the schematic.� Placement of the components is the next step.� Routing of tracks can be done manually or automatically.� All PCB design rules are taken care by the DRC.� Modifications in PCB can be made by changing the schematic directly.directly.

� The tool generates a .gerb file that can be directly fed to the CNC machine for PCB fabrication.

13 OrCAD of Cir. Sim. and PCB Design ANISH GOEL

Complex PCB Generation from Schematic

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Testing and Verification� Testing of the circuit is done by applying all the possible combinations of inputs and verifying the expected outputs.

� Fault during testing can be analyzed by looking at the schematic directly.

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Targets to the students� Recollect the basic knowledge of these courses:

� Electronic devices and circuit.� Digital Circuits.� Linear electronic circuit.� Microprocessors and interfacing.

For knowledge about electronic components:

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� For knowledge about electronic components:� Electronic Engg. Materials and Components.

� Combine all these knowledge to develop circuits like:� Amplifiers and filters (LEC)� Counters and ALU (DC and MuP)� Any other application oriented circuit.

Sample Design

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Sample Design cont…

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Workshop on OrCAD

� Workshop on OrCAD covers the following topics:� Basic schematic design.� Simulation using PSPICE.� Circuit design for complex circuitry.� Generating netlist file.� Generating PCB from netlist.

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� Generating PCB from netlist.� Placing components.� Routing connections.� Generating gerb file by post processor.� Taking films for PCB fabrication.

� Students will be provided with an evaluation version of the software that holds good for 6months to 1 year.

Thank you …� This presentation is also available at:

www.discovermechatronics.blogspot.com

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