Microchip Technology dsPICDEM SMPS Buck Development Board User guide

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dsPICDEM™ SMPS Buck

Development Board

User’s Guide

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code hopping devices, Serial EEPROMs,

dsPICDEM™ SMPS BUCK

DEVELOPMENT BOARD

USER’S GUIDE

Table of Contents

Preface ........................................................................................................................... 1

Chapter 1. Introduction

1.1 Overview ........................................................................................................ 7

1.2 dsPICDEM™ SMPS Buck Development Board Kit ........................................ 8

1.3 dsPICDEM™ SMPS Buck Development Board Features .............................. 8

Chapter 2. Hardware Overview

2.1 Connectors ................................................................................................... 11

2.2 User Interface Hardware .............................................................................. 14

2.3 Program or Debug Selection Switch (SW2) ................................................. 17

Chapter 3. Using the dsPIC30F2020 Device

3.1 Tutorial Overview ......................................................................................... 19

3.2 Creating the Project ...................................................................................... 19

3.3 Building the Code ......................................................................................... 26

3.4 Programming the Chip ................................................................................. 28

3.5 Debugging the Code .................................................................................... 33

Chapter 4. Demonstration Program Operation

4.1 Demonstration Program ............................................................................... 37

4.2 Demonstration Code .................................................................................... 39

4.3 Other Code Examples .................................................................................. 40

Appendix A. Schematic and Layouts

Index ............................................................................................................................. 45

Worldwide Sales and Service .................................................................................... 46

dsPICDEM™ SMPS Buck Development Board

NOTES:

dsPICDEM™ SMPS BUCK

DEVELOPMENT BOARD

USER’S GUIDE

Preface

NOTICE TO CUSTOMERS

All documentation becomes dated, and this manual is no exception. Microchip tools and documentation are constantly evolving to meet customer needs, so some actual dialogs and/or tool descriptions may differ from those in this document. Please refer to our web site (www.microchip.com) to obtain the latest documentation available.

Documents are identified with a “DS” number. This number is located on the bottom of each page, in front of the page number. The numbering convention for the DS number is “DSXXXXXA”, where “XXXXX” is the document number and “A” is the revision level of the document.

For the most up-to-date information on development tools, see the MPLAB Select the Help menu, and then Topics to open a list of available on-line help files.

IDE on-line help.

This document contains general information that is useful to know before using the dsPICDEM™ SMPS Buck Development Board.

Items discussed in this preface include:

• About this Guide

• Conventions Used in this Guide

• Warranty Registration

• Recommended Reading

• The Microchip Web Site

• Development Systems Customer Change Notification Service

• Customer Support

• Document Revision History

ABOUT THIS GUIDE

This document describes how to use the dsPICDEM™ SMPS Buck Development Board development tool. The manual layout is as follows:

• Chapter 1. “Introduction” – This chapter introduces the dsPICDEM™ SMPS Buck Development Board and provides a brief descriptions of the hardware.

• Chapter 2. “Hardware Overview” – This chapter describes the dsPICDEM™ SMPS Buck Development Board hardware.

• Chapter 3. “Using the dsPIC30F2020 Device” – This chapter goes through a basic step by step process for getting your dsPICDEM™ SMPS Buck Development Board up and running with the MPLAB a dsPIC30F2020 device.

• Chapter 4. “Demonstration Program Operation” – This chapter describes the operation of the dsPICDEM™ SMPS Buck Development Board.

• Appendix A. “Schematic and Layouts” – This section illustrates the dsPICDEM™ SMPS Buck Development Board layout and provides hardware schematic diagrams.

In-Circuit Debugger 2 (ICD 2) using

dsPICDEM™ SMPS Buck Development Board

CONVENTIONS USED IN THIS GUIDE

This manual uses the following documentation conventions:

DOCUMENTATION CONVENTIONS

Description Represents Examples

Arial font:

Italic characters Referenced books MPLAB

Emphasized text ...is the only compiler...

Initial caps A window the Output window

A dialog the Settings dialog A menu selection select Enable Programmer

Quotes A field name in a window or

dialog

Underlined, italic text with right angle bracket

Bold characters A dialog button Click OK

N‘Rnnnn A number in verilog format,

Text in angle brackets < > A key on the keyboard Press <Enter>, <F1>

Courier New font:

Plain Courier New Sample source code #define START

Italic Courier New A variable argument file.o, where file can be

Square brackets [ ] Optional arguments mcc18 [options] file

Curly brackets and pipe character: { | }

Ellipses... Replaces repeated text var_name [,

A menu path File>Save

A tab Click the Power tab

where N is the total number of digits, R is the radix and n is a digit.

Filenames autoexec.bat File paths c:\mcc18\h Keywords _asm, _endasm, static Command-line options -Opa+, -Opa- Bit values 0, 1 Constants 0xFF, ‘A’

Choice of mutually exclusive arguments; an OR selection

Represents code supplied by user

IDE User’s Guide

“Save project before build”

4‘b0010, 2‘hF1

any valid filename

[options] errorlevel {0|1}

var_name...] void main (void)

{ ... }

WARRANTY REGISTRATION

Please complete the enclosed Warranty Registration Card and mail it promptly. Sending in the Warranty Registration Card entitles users to receive new product updates. Interim software releases are available at the Microchip web site.

1.1 OVERVIEW

Figure 1-1 is a block diagram of the dsPICDEM™ SMPS Buck Development Board, A dsPIC30F2020 DSC controls two independent DC/DC synchronous buck converters, providing closed-loop Proportional, Integral, Derivative (PID) control in software to maintain desired output voltage levels. The dsPIC sary memory and peripherals for A/D conversion, PWM generation and general purpose I/O, precluding the need to perform these functions in external circuitry.

dsPICDEM™ SMPS BUCK

DEVELOPMENT BOARD

Chapter 1. Introduction

DSC device provides the neces-

USER’S GUIDE

FIGURE 1-1: SYNCHRONOUS BUCK CONVERTER BLOCK DIAGRAM

LOADBUCK CONVERTER 1

Communication

AN4

dsPIC30F2020

AN0

AN1

OC1

AN2

AN3

PWM1H PWM1L

PWM2H

PWM2L

VIN

BUCK CONVERTER 2

VIN

VOUT1

VOUT2

dsPICDEM™ SMPS Buck Development Board

dsPIC DSC SMPS devices are specifically designed to provide low-cost, efficient control of a wide range of power supply topologies. Their specialized peripherals facilitate closed-loop feedback control of switched mode power supplies while also providing communications for remote monitoring and supervisory control.

The dsPICDEM™ SMPS Buck Development Board aids in rapid development of multiple buck converters using dsPIC30F1010/2020 Digital Signal Controllers. The dsPIC30F1010/2020 devices offer these features and capabilities:

• Integrated program and data memory on a single chip

• Ultra fast interrupt response time and hardware interrupt priority logic

• 2000 ksps, on-chip ADC with four dedicated sample/hold circuits for multiple loop control

• Four independent, high-resolution PWM generators specially designed to support different power topology

• Four analog comparators for system protection

• On-chip system communications (I

• On-chip RC oscillator for lower system cost

• High-current sink/source I/O pins: 25 mA/25mA

• 30 MIPS performance CPU

1.2 dsPICDEM™ SMPS BUCK DEVELOPMENT BOARD KIT

C/SPI/UART)

The dsPICDEM™ SMPS Buck Development Board kit contains these items:

• dsPICDEM™ SMPS Buck Development Board

• dsPICDEM™ SMPS Buck Development Board CD containing example code and relevant documentation

1.3 dsPICDEM™ SMPS BUCK DEVELOPMENT BOARD FEATURES

The dsPICDEM™ SMPS Buck Development Board incorporates these features:

1.3.1 Power Stages

• Two synchronous buck converter power stages

• Voltage/current measurement for digital control of buck converters

• In-rush current limiting

• Switchable 5Ω/5W resistive load on VOUT1

• Buck Converter 1 output (VOUT1) on J1 connector for external loading

• Buck Converter 2 output (VOUT2) on J2 connector for external loading

1.3.2 Input/Output Controls

• Three 5 kΩ Potentiometers (R29,R30 and R35)

• Two push button switches (S2 and S4)

• Master Clear push button switch (S3)

• LED indicator (LED3)

Introduction

1.3.3 Development Board Power

• Auxiliary power input (P1and P2) – 7V to 15V (9V nominal)

• 9 volt power input (J2)

Note: This power input is compatible with the 9 volt power supply that is part of

the MPLAB ICD 2 In-Circuit Debugger (DV164007).

• LED power-on indicator (LED1)

• On-board 5V DC, low-dropout regulator

1.3.4 Communication Ports

• One RS232 port (J6)

• MPLAB ICD 2 programming connector (J5)

• SW2 selection of programming interface to the MPLAB ICD 2 Debugger/Programmer

dsPICDEM™ SMPS Buck Development Board

NOTES:

Chapter 2. Hardware Overview

This chapter describes the dsPICDEM™ SMPS Buck Development Board hardware elements and identifies the hardware components. The topics covered include:

• Connectors

• User Interface Hardware

• Program or Debug Selection Switch (SW2)

2.1 CONNECTORS

Figure 2-1 shows the hardware connection (MPLAB ICD 2 and power supply) to the dsPICDEM™ SMPS Buck Development Board.

dsPICDEM™ SMPS BUCK

DEVELOPMENT BOARD

USER’S GUIDE

FIGURE 2-1: dsPICDEM™ SMPS BUCK DEVELOPMENT BOARD

CONNECTED TO MPLAB

Expansion Header

ICD 2 AND POWER SUPPLY

ICD Connector

RS232 Connector

VOUT Connectors

VOUT2

VOUT1

Input Power Connector

TABLE 2-1: BUCK CONVERTER BOARD CONNECTORS

No Hardware Elements

1 Input Power Connector (J2) 2 RS232 connector (J6) 3 Programming/debugging connector (J5) 4 VOUT1 Connector (J1) 5 VOUT2 Connector (J3) 6 Expansion Header (J7)

dsPICDEM™ SMPS Buck Development Board

2.1.1 Input Power Connector

The dsPICDEM™ SMPS Buck Development Board obtains +9V power from a power connector for a +9V AC/DC wall adapter as well as auxiliary power connection points (AUX PWR IN). A separate +5V DC regulator provides the operating voltage (V required by the dsPIC30F2020 device.

2.1.2 ICD Connector

An RJ11 female connector (J5) connects the MPLAB® ICD 2 to the dsPIC30F2020 device for programming and debugging.

2.1.3 RS-232 Serial Port

An RS-232 serial communication port (J6) is provided for monitoring and controlling the power supply by a remote processor. The PGM DEBUG switch (SW2) must be in set in program mode position (PGM) to communicate via the UART.

2.1.4 VOUT1

An external load can be connected to VOUT1 through connector J1. An on-board 5Ω 5 watt resistor is connected at the output of VOUT1 through MOSFET U6 to optionally load the first buck converter circuit. This load can be enabled or disabled in software. See Figure A-3: “dsPICDEM™ SMPS Buck Development Board Schematic 2 of 3”

DD)

2.1.5 VOUT2

An external load can be connected to VOUT2 through connector J1.See Figure A-4: “dsPICDEM™ SMPS Buck Development Board Schematic 3 of 3”

2.1.6 Expansion Header

Header J7 is an expansion connector that matches the dsPIC30F2020 device pins (see Table 2-2 for pin usage information).

Hardware Overview

TABLE 2-2: DEVICE PINS IN EXPANSION CONNECTOR

Pin Number

Primary

Assignment Primary Use

1MCLR

Master Clear (Reset) 2 AN0/RB0 Analog Input 0 (Buck Converter 1 current) 3 AN1/RB1 Analog Input 1 (Buck Converter 1 voltage) 4 AN2/RB2 Analog Input 2 (Buck Converter 2 current) 5 AN3/RB3 Analog Input 3 (Buck Converter 2 voltage) 6 AN4/RB4 Analog Input 4 (Input Voltage) 7 AN5/RB5 Analog Input 5 (Potentiometer R29) 8V

SS Ground reference for logic and I/O pins

9 AN6/OSCI/RB6 Analog Input 6 (Potentiometer R30) 10 AN7/OSCO/RB7 Analog Input 7 (Potentiometer R35) 11 EMUD1/RE7 ICD secondary communication channel data 12 EMUC1/RE6 ICD secondary communication channel clock 13 V

DD Positive supply for logic and I/O pins

14 OC2/RF6 Compare output 15 OC1/RD0 Compare output 16 RA9 Port A pin (LED3) 17 U1TX/PGC/RF7 UART1 Receive 18 U1RX/PGD/RF8 UART1 Transmit 19 V

SS Ground reference for logic and I/O pins

20 VDD Positive supply for logic and I/O pins 21 PWM3H/RE5 PWM 3 High Output (Push Button Switch S2) 22 PWM3L/RE4 PWM 3 Low Output (Push Button Switch S4) 23 PWM2H/RE3 PWM 2 High Output (Buck Converter 2) 24 PWM2L/RE2 PWM 2 Low Output (Buck Converter 2) 25 PWM1H/RE1 PWM 1 High Output (Buck Converter 1) 26 PWM1L/RE0 PWM 1 Low Output (Buck Converter 1) 27 AV 28 AV

SS Ground reference for analog module DD Positive supply for analog module

dsPICDEM™ SMPS Buck Development Board

2.2 USER INTERFACE HARDWARE

Figure 2-2 identifies the hardware elements that comprise the user interface (jumpers, switches, LEDs and potentiometers) on the dsPICDEM™ SMPS Buck Development Board.

FIGURE 2-2: JUMPERS/LED/SWITCHES/POTENTIOMETER

Jumpers

MCLR Reset Switch

JP1JP3 JP4 JP2 JP5 J4 J8

LED1 LED3 R29 R30 R35

Potentiometers

S2 S4

SwitchesLEDs

2.2.1 Jumpers

The dsPICDEM™ SMPS Buck Development Board has seven jumpers that determine how features on the buck converters are used. Table 2-3 lists these jumpers and their functions.

TABLE 2-3: JUMPER DESCRIPTIONS

Jumper Description

JP1 Buck Converter 1 Input Select

ON: Connects the Input power to buck converter 1 OFF: Input to buck converter 1 is left open

JP2 Buck Converter 1 Load Drive

ON: Turn ON buck converter 1 load (5 OFF: On board load is disabled

JP3 Buck Converter 2 Input Select

ON: Connects the Input power to buck converter 2 OFF: Input to buck converter 2 is left open

Ω/5W) using OC1/RD0 pin

Hardware Overview

TABLE 2-3: JUMPER DESCRIPTIONS (CONTINUED)

Jumper Description

JP4 Buck Converter 1 Synchronous MOSFET Drive

ON: Enable Synchronous MOSFET drive for buck converter 1 OFF: Disable Synchronous MOSFET drive for buck converter 1

JP5 Buck Converter 2 Synchronous MOSFET Drive

ON: Enable Synchronous MOSFET drive for buck converter 2 OFF: Disable Synchronous MOSFET drive for buck converter 2

J4 Buck Converter 1 Current Sense Position Select

Jumper J4 is connected to the buck converter 1 output bulk capacitor. It allows the user to select the current sense resistor position for different applications.

Position Function

1-2 Current sense resistor senses output load of converter 1 2-3 Current sense resistor senses inductor current of converter 1

J8 Buck Converter 2 Current Sense Position Select

Jumper J8 is connected to the buck converter 2 output bulk capacitor. It allows the user to select the current sense resistor position for different applications.

Position Function

1-2 Current sense resistor senses load current of converter 2 2-3 Current sense resistor senses inductor current of converter 2

2.2.2 Switches, LEDs and Potentiometers

The dsPICDEM™ SMPS Buck Development Board has 2 switches, 3 potentiometers and one LED for user applications. The board also has one power ON status LED and device reset switch.

TABLE 2-4: PUSH BUTTONS, POTENTIOMETERS AND LEDS

Label Hardware Elements

S2, S4 Push button switches connected to port pins RE5 and RE4, respectively, for user

applications. When momentarily depressed, the switch connects the respective port pin to ground (Logical ‘0’).

R29, R30,

R35 LED3 User programmable LED; programmed by writing to port pin RE9. LED1 Power-on status LED; indicates status of 5V regulator.

S3 Reset switch. When momentarily depressed, the switch asserts the MCLR

User potentiometers connected to analog input pins (AN5, AN6 and AN7), respectively, for user applications.

to the dsPIC

DSC device for Reset.

signal

2.2.3 Test Points

The dsPICDEM™ SMPS Buck Development Board provides seven power test points that can be used to debug the power stage and eight PWM test points that can be used to check the PWM signal and gate drive to buck converter 1 and 2. These test points are described in Table 2-5 and Table 2-6, respectively.

dsPICDEM™ SMPS Buck Development Board

FIGURE 2-3: TEST POINTS

Power Test Points

P2 P1 TP2 TP1 P14 P9 P3

P8 P6 P5 P7 P10 P13 P12 P11

PWM Test Points

TABLE 2-5: POWER TEST POINTS

Test Point Description

TP1 5V DC Regulator Output TP2 5V DC Regulator Output Ground

P1 Input Supply Voltage P2 Input Supply Ground P3 Buck Converter Output Ground P9 Buck Converter 1 Switching Point

P14 Buck Converter 2 Switching Point

Note 1: All ground test points are shorted

(1)

TABLE 2-6: PWM TEST POINTS

Test Point

P5 Buck Switch PWM signal (Buck Converter 1) P6 Synchronous Switch PWM signal (Buck Converter 1) P7 Buck Switch PWM signal (Buck converter 2)

P8 Synchronous Switch PWM signal (Buck Converter 2) P10 Buck Switch Gate Drive (Buck Converter 1) P11 Synchronous Switch Gate Drive (Buck Converter 1) P12 Buck Switch Gate Drive (Buck Converter 2) P13 Synchronous Switch Gate Drive (Buck Converter 2)

Signal

Hardware Overview

2.3 PROGRAM OR DEBUG SELECTION SWITCH (SW2)

The dsPIC30F2020 device program pins (PGC/PGD) are multiplexed with the UART pins (U1RX and U1TX). A DIP switch (SW2) selects whether the default programming pin pair (PGC/PGC) are used to program the device. Because PGC and PGD are multiplexed with the UART pins, the pins can only be used to program the device. Debugging is not possible with PGC/EMUC and PGD/EMUD.

When SW2 is in the PGM position, the PGC/PGD and PGC1/PGD1 pins are connected to the ICD 2. This configuration allows you to program the device with either the default programming pin pair (PGC/PGD) or the first set of auxiliary programming pins (PGC1/PGD1). Emulation and debugging in not possible when SW2 is in the PGM position and the default programming/emulation pins are selected (via the Configuration bits).

When SW2 is in the DEBUG position, PGC1/EMUC1 and PGD1/EMUD1 must be selected as the debugging pin pair in the Configuration bit settings window. Both programming and debugging are possible in this configuration.

dsPICDEM™ SMPS Buck Development Board

NOTES:

Chapter 3. Using the dsPIC30F2020 Device

This chapter is a self-paced tutorial to get you started using the dsPICDEM™ SMPS Buck Development Board with its on-board dsPIC30F2020 device. Information is provided on these topics:

• Tutorial Overview

• Creating the Project

• Building the Code

• Programming the Chip

• Debugging the Code

3.1 TUTORIAL OVERVIEW

The tutorial demonstrates the main features of MPLAB IDE Integrated Development Environment and the MPLAB ICD 2 In-Circuit Debugger as they are used with the dsPICDEM™ SMPS Buck Development Board. On completing this tutorial, you should be able to:

• Create a project using the Project Wizard.

• Assemble and link the code and set the Configuration bits.

• Set up MPLAB IDE to use the MPLAB ICD 2 In-Circuit Debugger.

• Program the chip with the MPLAB ICD 2.

• View the code execution.

• View registers in a Watch window.

• Set a breakpoint and make the code halt at a chosen location.

• Use the function keys to Reset, Run, Halt and Single Step the code. Before you begin the tutorial, run the install program on the dsPICDEM™ SMPS Buck

Development Board CD. The default installation location is:

c:\Program Files\Microchip\Sync Buck Board\Firmware\DualBuck

dsPICDEM™ SMPS BUCK

DEVELOPMENT BOARD

USER’S GUIDE

3.2 CREATING THE PROJECT

The first step is to create a project and workspace in MPLAB IDE. Usually, you will have one project in one workspace.

Note: These instructions presume the use of MPLAB IDE 7.43 or newer.

A project contains the files needed to build an application (source code, linker script files, etc.) along with their associations to various build tools and build options.

A workspace contains one or more projects and information on the selected device, debug tool and/or programmer, open windows and their location, and other IDE configuration settings. MPLAB IDE provides a Project Wizard to help create new projects.

dsPICDEM™ SMPS Buck Development Board

3.2.1 Select a dsPIC DSC Device

• Start MPLAB IDE.

• Close any workspace that might be open (File>Close Workspace

• From the Project menu, select Project Wizard.

• From the Welcome screen, click Next> to display the Project Wizard Step One dialog as shown in the Figure 3-1.

FIGURE 3-1: PROJECT WIZARD, STEP 1, SELECT A DEVICE

• From the Device: pull-down list, select dsPIC30F2020 and click Next>. The Project Wizard Step Two dialog displays as shown in Figure 3-2.

Using the dsPIC30F2020 Device

FIGURE 3-2: PROJECT WIZARD STEP 2, SELECT LANGUAGE

TOOLSUITE

3.2.2 Select Language Toolsuite

• From the Active Toolsuite: pull-down menu, select Microchip ASM30 Toolsuite. This tool suite includes the assembler and linker that will be used.

Note: If you are creating a project with source files written in a language other

than Microchip assembly, choose the appropriate language tool suite from the drop-down selections.

• In the Toolsuite Contents block, select MPLAB ASM30 Assembler (pic30-as.exe).

• In the Location block, click Browse... and navigate to:

C:\Program Files\Microchip\MPLAB ASM30 Suite\bin\pic30-as.exe

• With MPLAB LINK 30 Object Linker (pic30-Id.exe) selected in Toolsuite Con- tents, click Browse... and navigate to:

C:\Program Files\Microchip\MPLAB ASM30 Suite\bin\pic30-id.exe

•Click Next> to continue. The Project Wizard Step Three dialog displays as shown in Figure 3-3.

dsPICDEM™ SMPS Buck Development Board

FIGURE 3-3: PROJECT WIZARD, STEP 3, NAME YOUR PROJECT

3.2.3 Name Your Project

• In the Project Name text box, type DualBuck.

•Click Browse... and navigate to C:\DualBuck to place your project in the tutorial folder (create this folder if it does not already exist).

•Click Next> to continue. The Project Wizard Step Four dialog displays as shown in Figure 3-4.

Using the dsPIC30F2020 Device

FIGURE 3-4: PROJECT WIZARD, STEP 4, ADD FILES TO PROJECT

3.2.4 Add Files to Project

• In the left window, navigate to c:\...\Firmware\DualBuck and select these files:

SMPS_PID_Control.s

isr_traps.s

p30f2020.gld

p30f2020.inc

•Click Add>> to include these files in the project. The files appear with check boxes in the right-hand window.

• Check each box (to instruct the Project Wizard to copy these files to the project directory).

•Click Next> to continue.

• When the summary screen displays, click Finish.

• When the Save Workspace As window displays, type DualBuck.mcw in the “File name” field and save the workspace in C:\DualBuck (see Figure 3-5).

dsPICDEM™ SMPS Buck Development Board

FIGURE 3-5: SAVE WORKSPACE WINDOW

After the project wizard completes, the MPLAB IDE project window shows the

isr_traps.s and SMPS_PID_Control.s files in the Source Files folder, the p30f2020.inc file in the Header Files folder and the p30f2020.gld file in the Linker

Scripts folder (Figure 3-6).

FIGURE 3-6: MPLAB

IDE PROJECT WINDOW

Using the dsPIC30F2020 Device

A project and workspace has now been created in MPLAB IDE. DualBuck.mcw is the workspace file and DualBuck.mcp is the project file. Double click the SMPS_PID_Controls.s file in the project window to open the file. MPLAB IDE should now look similar to Figure 3-7.

FIGURE 3-7: MPLAB

IDE WORKSPACE WINDOWS

dsPICDEM™ SMPS Buck Development Board

3.3 BUILDING THE CODE

In this project, building the code consists of assembling the SMPS_PID_Controls.s and isr_traps.s files to create their respective object files, and isr_traps.o, and then linking the object files to create the DualBuck.hex and DualBuck.cof output files. The .hex file contains the data necessary to program the device and the .cof file contains additional information that lets you debug at the source code level.

Before building, there are settings required to tell MPLAB IDE where to find the include files and to reserve space for the extra debug code when the MPLAB ICD 2 is used. The following line is near the top of the SMPS_PID_Controls.s file:

.include "p30f2020.inc"

This line causes a standard include file to be used. Microchip provides these files with all the Special Function Register (SFR) labels already defined for convenience. To build the code, select Build Options>Project displays, as shown in Figure 3-8.

FIGURE 3-8: BUILD OPTIONS

from the Project menu. The Build Options dialog

SMPS_PID_Controls.o

Using the dsPIC30F2020 Device

3.3.1 Identify Assembler Include Path

• Select the General tab.

• At the Assembler Include Path, $(AINDIR) box, click Browse... and navigate to:

C:\Program Files\Microchip\MPLAB ASM30 Suite\Support\Inc

This path tells MPLAB IDE where to find the include files

•Click Apply and then click OK.

Note: The p30f2020.inc file was included when you added files to the project

folder (section Section 3.2.4 “Add Files to Project”). Selecting an Assembler Include Path in the manner described here allows you to link to the latest .inc file included with MPLAB IDE. Skip this step to use the .inc file in the project folder.

3.3.2 Link for ICD 2

It is necessary to tell the linker that the code should be built with the intention to debug. This sets aside RAM for the MPLAB ICD 2 to use during debugging. If this step is not done, the MPLAB ICD 2 will not function properly in Debug mode.

• On the Project Manager toolbar, select “Debug” from the drop-down box (see Figure 3-9)

FIGURE 3-9: LINK PROJECT FOR MPLAB

ICD 2

dsPICDEM™ SMPS Buck Development Board

3.3.3 Build the Project

•Select Project>Build All.

• Observe the progress of the build in the Output window as shown in Figure 3-10.

FIGURE 3-10: BUILD OUTPUT WINDOW

3.4 PROGRAMMING THE CHIP

The MPLAB ICD 2 In-Circuit Debugger can be used to program and debug the dsPIC30F2020 device in-circuit on the dsPICDEM™ SMPS Buck Development Board.

Note: Before proceeding, make sure that the USB driver for the MPLAB ICD 2 has

been installed on your PC (see the “MPLAB User’s Guide” (DS51331) for more details regarding the installation of MPLAB ICD 2).

3.4.1 Setup the Device Configuration

• Use the Configure>Configuration Bits menu to display the configuration settings.

• Set up the Configuration bits as shown in Figure 3-11.

FIGURE 3-11: CONFIGURATION SETTINGS

ICD 2 In-Circuit Debugger

Using the dsPIC30F2020 Device

3.4.2 Connect the MPLAB ICD 2 In-Circuit Debugger

• Before connecting the MPLAB ICD 2 make sure SW2 is in the DEBUG position.

• Connect the MPLAB ICD 2 to the PC with the USB cable as shown in Figure 3-12).

• Connect the MPLAB ICD 2 to the dsPICDEM™ SMPS Buck Development Board with the short RJ-11 (telephone) cable.

• Apply +9V power to the board.

FIGURE 3-12: dsPICDEM™ SMPS BUCK DEVELOPMENT BOARD

CONNECTED TO MPLAB

ICD 2 IN-CIRCUIT DEBUGGER

dsPICDEM™ SMPS Buck Development Board

3.4.3 Enable MPLAB ICD 2 Connection

• From the Debugger menu, click Select Tool>MPLAB ICD 2 to designate the MPLAB ICD 2 as the debug tool in MPLAB IDE.

•Select Debugger>Connect to connect the debugger to the device. The MPLAB ICD 2 should report that it found the dsPIC30F2020 device, as shown in Figure 3-13.

•Select Debugger>Settings

• Select the Program tab.

•Check Allow ICD 2 to select memories and ranges, as shown in Figure 3-14. This setting will speed up operations by programming only a small part of the total program memory.

Note: The MPLAB ICD 2 may need to download the new firmware if this is the first

time the MPLAB ICD 2 is being used with a dsPIC30F device. If any errors are shown, double click the error message to get more information.

to display the MPLAB ICD 2 Debugger settings.

FIGURE 3-13: ENABLING MPLAB

ICD 2

Using the dsPIC30F2020 Device

FIGURE 3-14: SETTING PROGRAM MEMORY SIZE

3.4.4 Program the dsPIC30F2020

• From the Debugger menu, select Program. The Output window (Figure 3-15) displays the program steps as they occur.

• Observe the process in the Output window. When “MPLAB ICD 2 Ready” displays, the device is programmed and ready to run.

•Use the Debugger>Reset code.

menu to reset the code, then Debugger>Run to run the

dsPICDEM™ SMPS Buck Development Board

FIGURE 3-15: PROGRAMMING THE DSPIC30F2020 DEVICE

3.5 DEBUGGING THE CODE

The MPLAB ICD 2 In-Circuit Debugger can be used to run, halt and step the code. A breakpoint can be set to halt the program after the code has executed the instruction at the breakpoint. The contents of the RAM and registers can be viewed whenever the processor has been halted.

The MPLAB ICD 2 In-Circuit Debugger uses the following function keys to access the main debugging functions:

<F5> Halt <F6> Reset <F7> Single Step <F9> Run In addition, there are more functions available by right clicking on a line of source code.

The most important of these are “Set Breakpoint” and “Run to Cursor”.

3.5.1 Display the Code

• From the View menu, select View>Program Memory.

• On the Program Memory window, select the Symbolic tab, as shown in Figure 3-16.

• Press <F5> to halt the processor and press <F6> to reset. The program memory now shows a green arrow pointing to the line of code at address 0.

The instruction at this location is goto 0x000100. This code is added by the linker to make the program branch to the start of the code in the Lab1.c file. From location 0x000100 executable code starts.

Using the dsPIC30F2020 Device

FIGURE 3-16: PROGRAM MEMORY WINDOW

dsPICDEM™ SMPS Buck Development Board

3.5.2 Step the Program

• Press <F7> to single step the code. The green arrow now points to the code below _reset in the SMPS_PID_Control.s source code, as shown in Figure 3-17.

• Right click two lines below the green arrow and choose “Run to Cursor”. The green arrow then points to the line on which you right clicked.

• From the View menu, select View>Watch Figure 3-18.

•From the Add SFR pull-down list, display DTR1.

•Click Add SFR to add the DTR1 register to the Watch window.

• Next, select PWMCON1 from the pull-down list and click Add SFR.

• Repeat for the ADCON register.

• You will be able to view these registers change as you step through the code.

FIGURE 3-17: SOURCE CODE WINDOW

to open a Watch window as shown in

FIGURE 3-18: WATCH WINDOW DISPLAY

3.5.3 Set Break Point

• To set a breakpoint, right click a code line and select “Set Breakpoint” from the pop-up menu. As an example, find the following line of code and set a breakpoint on this line.

cp0 VIN_GOOD_FLAG

A red stop sign should appear in the gutter (gray bar on the left) of the source code window, as shown in Figure 3-19.

• Press <F9> to run the code. The program halts on the instruction following the breakpoint

Note: An alternate method is to simply double click the line. This feature may

need to be enabled using the Edit>Properties

FIGURE 3-19: SETTING BREAKPOINT

Using the dsPIC30F2020 Device

menu.

dsPICDEM™ SMPS Buck Development Board

NOTES:

Chapter 4. Demonstration Program Operation

The dsPIC30F2020 device supplied with the dsPICDEM™ SMPS Buck Development Board is pre-programmed with a demonstration program that illustrates simultaneous Proportional-Integral-Derivative (PID) control of the output voltage for the two buck circuits on the dsPICDEM™ SMPS Buck Development Board. This code is available on the CD that is provided with the dsPICDEM™ SMPS Buck Development Board kit. It can also be downloaded from the Microchip web site (www.microchip.com).

This section covers the following topics:

• Demonstration Program

• Demonstration Code

• Other Code Examples

4.1 DEMONSTRATION PROGRAM

The demonstration program provides simultaneous closed-loop control of the output voltage from both buck circuits on the dsPICDEM™ SMPS Buck Development Board. One PID loop controls a target voltage output (VOUT1) at 5V. The other PID loop controls a target voltage output (VOUT2) at 3.3V.

The PID control scheme consists of seven parameters. The main parameters are:

1. Proportional Error Gain (P-Gain) – This parameter produces a correction fac-

tor that is proportional to the magnitude of the output voltage error.

2. Integral Error Gain (I-Gain) – This parameter uses the cumulative voltage error

to generate a correction factor that eliminates any residual error due to limitations in offset voltages and measurement resolution.

3. Derivative Error Gain (D-Gain) – This parameter produces a correction factor

that is proportional to the rate of change of the output error voltage, which helps the system respond quickly to changes in system conditions.

Additional control parameters that are summed with the P, I, and D Gain terms are:

4. Second Derivative, or Jerk Error, Gain (J-Gain) – This parameter produces a

correction factor that is proportional to the change in the differential error (i.e., the derivative of the derivative). J-Gain is a high frequency term that tends to provide quick response to an impulse event.

5. Feed Forward Gain – This parameter produces a correction factor based on the

desired output voltage that is computed based on the magnitude of the input voltage, inductor current, and circuit attributes (i.e. inductor and capacitor values). This term allows the control loop to be proactive rather than reactive. In other words, when the input voltage changes, feed forward gain responds so that the control loop does not have to wait until the output voltage changes before making the appropriate gain correction.

6. Dead Time Gain – This parameter produces a correction factor, which compen-

sates for the fact that the feed forward gain term does not account for the energy lost due to the dead time of the PWM signal (the time when both MOSFETs are off).

7. Current-Limit Gain – This parameter limits the cumulative control gain when the

current is approaching its upper limit.

dsPICDEM™ SMPS BUCK

DEVELOPMENT BOARD

USER’S GUIDE

dsPICDEM™ SMPS Buck Development Board

The demonstration program requires no manual preparation except to connect 9V power to the board. You can verify the VOUT1 and VOUT2 voltage levels by measuring them at the output terminals (J1 and J3, respectively).

If you installed the software that came on the dsPICDEM™ SMPS Buck Development Board CD, the demonstration program source code is located in the following folder on your PC.

C:\Program Files\Microchip\Sync Buck Board\Firmware\DualBuck

Instructions for programming the dsPIC30F2020 are provided in the Readme file that is included in the DualBuck folder. Chapter 3 also describes how to program the dsPIC30F2020 using the ICD 2. Figure 4-1 illustrates the program flow of the demonstration program.

FIGURE 4-1: SMPS DEMONSTRATION PROGRAM FLOW CHART

START

Initialization Routines:

• Peripherals – ADC, PWM, Timers, GPIO, etc.

• Variables – PID Gain Terms, Data Buffers

• Constants – Desired Voltage, Current Limit, etc.

• Interrupts – ADC, Timers

• Set Soft Start Flag

• System Stabilization

Soft Start Routine

Soft

Start

Routine

Yes

Idle Loop Functions:

• Check VIN

• Check Soft Start Flag

• Check/Reset Fault Timers and Flags

• Perform non-critical functions here (e.g. user application tasks)

Does

Fault Condition

Exist

Soft Start

Active

Fault-Check Routine

Yes

Disable

Outputs

ADC Interrupt

ADC Interrupt Routines:

• Measure VOUT

• Calculate PID Gain Parameters

• Update PWM Duty Cycle

END

4.2 DEMONSTRATION CODE

4.2.1 System Initialization

When power is applied to the board, the program starts by executing these system initialization routines:

• Peripherals – The required peripherals (PWM, ADC, Timers, GPIO) are configured and enabled.

• Variables – Program variables are defined. RAM locations and register usage are also defined and documented.

• Constants – Program constants are defined, including reference setpoints for both VOUT1 and VOUT2, input voltage, current limits, fault conditions, PWM periods and Timer periods.

• Interrupts – The ADC and Timer Interrupts are set up and enabled.

• Soft Start – The Soft Start flag is set

• System Stabilization – All outputs are discharged to ensure a stable value at startup.

4.2.2 Fault Check

The program checks the ADC for input undervoltage and output overvoltage conditions. If a fault occurs, the PWM outputs are disabled until the fault condition is cleared. If no fault is detected, the program proceeds.

Demonstration Program Operation

4.2.3 Soft Start

If the Soft Start flag is set, the Soft Start Routine ramps up the output voltage in an open-loop fashion to bring the system within the operating range of the PID control loop. This routine ensures that the output does not overshoot the desired voltage. It also limits the current at startup.

4.2.4 ADC Interrupt

The ADC Interrupt is the heart of the demo program. This routine takes up approximately 75% of the execution time. It performs all the PID calculations and applies any needed corrections to the output

Two simultaneous PID loops are being processed (one for VOUT1 and the other for VOUT2). Each loop has its own variables, constants and peripheral initialization.

Key points to note are:

• The ADC Interrupt can occur at any time during program execution, and

• It takes priority over any other tasks that the program is performing.

4.2.5 System Idle Loop

All auxiliary functions are performed in the System Idle routine. This is the time available to the CPU while the demo program is waiting for an ADC Interrupt. Non-critical functions can be performed in this loop. During this time the input voltage, fault timers and Soft Start flag are checked.

dsPICDEM™ SMPS Buck Development Board

4.3 OTHER CODE EXAMPLES

There are several other code examples included on the dsPICDEM™ SMPS Buck Development Board CD. Please refer to the Readme files located in each code example folder for details on what each code example demonstrates. Check the Microchip website (www.microchip.com) for the latest updates to these code examples and for additional code examples.

dsPICDEM™ SMPS BUCK

DEVELOPMENT BOARD

USER’S GUIDE

Appendix A. Schematic and Layouts

This Appendix provides a layout drawing of the printed circuit board followed by schematics for the dsPICDEM™ SMPS Buck Development Board.

FIGURE A-1: dsPICDEM™ SMPS BUCK DEVELOPMENT BOARD LAYOUT

dsPICDEM™ SMPS Buck Development Board

FIGURE A-2: dsPICDEM™ SMPS BUCK DEVELOPMENT BOARD SCHEMATIC 1 OF 3

RXD

TXD

P1L

VDD

P1H

RE5

P2L

P2H

RE4

RA9

VDD

OC1

0.1uF

C19

MCLR

VDD

OC2

AN0

AN4

AN1

AN2

AN3

MCLR

AN5

2.2K

R32

R24

RXD

TXD

VDD

AN6

AN7

EMUD1

EMUC1

RXD

EMUD1

TXD

EMUC1

VDD

0.1uF

C16

0.1uF

C21

0.1uF

C12

VDD

C20

0.1uF

C15

VDD

MCLR

RE5

C17

0.1uF

VDD

C14

0.1uF

C18

0.1uF

VDD VDD

RE4

AN7

C32

0.01uF

P1H

P1L

P2H

P2L

VDD

MCLR

AN1

AN0

AN2

AN3

RE5

RE4

AN5

0.1uF

AN4

0.01uF

C11

500pF

C10

0.01uF

C23

500pF

C13

TXD

RXD

RA9

VDD

AN6

AN7

OC1

OC2

VDD

EMUC1

EMUD1

VDD

AN6

C31

0.01uF

VDD

AN5

0.01uF

VDD

RA9

Schematic and Layouts

FIGURE A-3: dsPICDEM™ SMPS BUCK DEVELOPMENT BOARD SCHEMATIC 2 OF 3

VOUT1

0.1uF

C24

5R 5W

330uF 16V

IN4001

4.7K

R17

JP2

1K 1%

VDD

0.050 R 1%

39uH

IRFR5305

P10

1N4746A 18V

1K 1%

R10

MBRS340

27R

R12

P11

U2:B

4.7K

R14

27R

JP4

VDD

100 uF 10V

U2:A

4.7K

C35

1.0uF

1N4746A 18V

JP1

VIN

3K 1%

C28

470uF 25V

C37

470uF 25V

R13

VIN

470RR2470R

1K 1%

R11

P1L

AN1

AN0

P1H

AN4

OC1

C22

1N4001MOD

470uF 15V

dsPICDEM™ SMPS Buck Development Board

FIGURE A-4: dsPICDEM™ SMPS BUCK DEVELOPMENT BOARD SCHEMATIC 3 OF 3

VOUT2

330uF 16V

0.1uF

330uF 16V

C25

R36

P14

IRFR5305

1K 1%

R20

VDD

0.050R 1%

39uH

U12

P13

1N4746A 18V

D10

1K 1%

R22

MBRS340

U15

27R

R18

P12

U11:B

4.7K

R34

27R

R15

U11:A

4.7K

C34

D11

JP3

C33

C36

VIN

R19

1.0uF 1N4746A 18V

470uF 25V

JP5

470R

P2L

AN3

AN2

P2H

dsPICDEM™ SMPS BUCK

Index

DEVELOPMENT BOARD

USER’S GUIDE

Block Diagram

Synchronous Buck Converter ............................. 7

Board Features .......................................................... 8

Communication Ports................................................. 9

Connectors............................................................... 11

Current Limit Gain.................................................... 37

Customer Notification Service.................................... 4

Customer Support...................................................... 5

Dead Time Gain....................................................... 37

Derivative Error Gain (D-Gain)................................. 37

Development Board Power........................................ 9

Documentation

Conventions........................................................ 2

Layout ................................................................. 1

Expansion Header ................................................... 12

Feed Forward Gain.................................................. 37

ICD Connector ......................................................... 12

Input Power Connector ............................................ 12

Input/Output Controls................................................. 8

Integral Error Gain (I-Gain) ...................................... 37

Internet Address......................................................... 3

Jerk Error Gain (J-Gain)........................................... 37

Jumper Descriptions ................................................ 14

Kit

dsPICDEM™ SMPS Buck Development Board.. 8

Microchip Internet Web Site....................................... 3

PID Control............................................................... 37

Power Stages............................................................. 8

Power Test Points.................................................... 16

Program/Debug Switch ...................................... 16

Proportional Error Gain (P-Gain).............................. 37

PWM Test Points ..................................................... 16

, 17

Reading, Recommended ........................................... 3

RS-232 Serial Port ................................................... 12

Second Derivative Gain (J-Gain) ............................. 37

Synchronous Buck Converter Block Diagram............ 7

Test Points ............................................................... 15

VOUT1 ..................................................................... 12

VOUT2 ..................................................................... 12

Warranty Registration ................................................ 3

WWW Address........................................................... 3

WORLDWIDE SALES AND SERVICE

AMERICAS

Corporate Office

2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 480-792-7200 Fax: 480-792-7277 Technical Support: http://support.microchip.com Web Address: www.microchip.com

Atlanta

Alpharetta, GA Tel: 770-640-0034 Fax: 770-640-0307

Boston

Westborough, MA Tel: 774-760-0087 Fax: 774-760-0088

Chicago

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Addison, TX Tel: 972-818-7423 Fax: 972-818-2924

Detroit

Farmington Hills, MI Tel: 248-538-2250 Fax: 248-538-2260

Kokomo

Kokomo, IN Tel: 765-864-8360 Fax: 765-864-8387

Los Angeles

Mission Viejo, CA Tel: 949-462-9523 Fax: 949-462-9608

Santa Clara

Santa Clara, CA Tel: 408-961-6444 Fax: 408-961-6445

Toronto

Mississauga, Ontario, Canada Tel: 905-673-0699 Fax: 905-673-6509

ASIA/PACIFIC

Asia Pacific Office

Suites 3707-14, 37th Floor Tower 6, The Gateway Habour City, Kowloon Hong Kong Tel: 852-2401-1200 Fax: 852-2401-3431

Australia - Sydney

Tel: 61-2-9868-6733 Fax: 61-2-9868-6755

China - Beijing

Tel: 86-10-8528-2100 Fax: 86-10-8528-2104

China - Chengdu

Tel: 86-28-8665-5511 Fax: 86-28-8665-7889

China - Fuzhou

Tel: 86-591-8750-3506 Fax: 86-591-8750-3521

China - Hong Kong SAR

Tel: 852-2401-1200 Fax: 852-2401-3431

China - Qingdao

Tel: 86-532-8502-7355 Fax: 86-532-8502-7205

China - Shanghai

Tel: 86-21-5407-5533 Fax: 86-21-5407-5066

China - Shenyang

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Tel: 86-27-5980-5300 Fax: 86-27-5980-5118

China - Xian

Tel: 86-29-8833-7250 Fax: 86-29-8833-7256

ASIA/PACIFIC

India - Bangalore

Tel: 91-80-4182-8400 Fax: 91-80-4182-8422

India - New Delhi

Tel: 91-11-4160-8631 Fax: 91-11-4160-8632

India - Pune

Tel: 91-20-2566-1512 Fax: 91-20-2566-1513

Japan - Yokohama

Tel: 81-45-471- 6166 Fax: 81-45-471-6122

Korea - Gumi

Tel: 82-54-473-4301 Fax: 82-54-473-4302

Korea - Seoul

Tel: 82-2-554-7200 Fax: 82-2-558-5932 or 82-2-558-5934

Malaysia - Penang

Tel: 60-4-646-8870 Fax: 60-4-646-5086

Philippines - Manila

Tel: 63-2-634-9065 Fax: 63-2-634-9069

Singapore

Tel: 65-6334-8870 Fax: 65-6334-8850

Taiwan - Hsin Chu

Tel: 886-3-572-9526 Fax: 886-3-572-6459

Taiwan - Kaohsiung

Tel: 886-7-536-4818 Fax: 886-7-536-4803

Taiwan - Taipei

Tel: 886-2-2500-6610 Fax: 886-2-2508-0102

Thailand - Bangkok

Tel: 66-2-694-1351 Fax: 66-2-694-1350

EUROPE

Austria - Wels

Tel: 43-7242-2244-39 Fax: 43-7242-2244-393

Denmark - Copenhagen

Tel: 45-4450-2828 Fax: 45-4485-2829

France - Paris

Tel: 33-1-69-53-63-20 Fax: 33-1-69-30-90-79

Germany - Munich

Tel: 49-89-627-144-0 Fax: 49-89-627-144-44

Italy - Milan

Tel: 39-0331-742611 Fax: 39-0331-466781

Netherlands - Drunen

Tel: 31-416-690399 Fax: 31-416-690340

Spain - Madrid

Tel: 34-91-708-08-90 Fax: 34-91-708-08-91

UK - Wokingham

Tel: 44-118-921-5869 Fax: 44-118-921-5820

10/19/06

Microchip Technology dsPICDEM SMPS Buck Development Board User guide

Specifications and Main Features

Frequently Asked Questions

User Manual

Preface

1.1 OVERVIEW

Chapter 1. Introduction

FIGURE 1-1: SYNCHRONOUS BUCK CONVERTER BLOCK DIAGRAM

1.2 dsPICDEM™ SMPS BUCK DEVELOPMENT BOARD KIT

1.3 dsPICDEM™ SMPS BUCK DEVELOPMENT BOARD FEATURES

1.3.1 Power Stages

1.3.2 Input/Output Controls

1.3.3 Development Board Power

1.3.4 Communication Ports

Chapter 2. Hardware Overview

2.1 CONNECTORS

TABLE 2-1: BUCK CONVERTER BOARD CONNECTORS

2.1.1 Input Power Connector

2.1.2 ICD Connector

2.1.3 RS-232 Serial Port

2.1.4 VOUT1

2.1.5 VOUT2

2.1.6 Expansion Header

TABLE 2-2: DEVICE PINS IN EXPANSION CONNECTOR

2.2 USER INTERFACE HARDWARE

FIGURE 2-2: JUMPERS/LED/SWITCHES/POTENTIOMETER

2.2.1 Jumpers

2.2.2 Switches, LEDs and Potentiometers

TABLE 2-4: PUSH BUTTONS, POTENTIOMETERS AND LEDS

2.2.3 Test Points

FIGURE 2-3: TEST POINTS

TABLE 2-5: POWER TEST POINTS

TABLE 2-6: PWM TEST POINTS

2.3 PROGRAM OR DEBUG SELECTION SWITCH (SW2)

Chapter 3. Using the dsPIC30F2020 Device

3.1 TUTORIAL OVERVIEW

3.2 CREATING THE PROJECT

3.2.1 Select a dsPIC DSC Device

FIGURE 3-1: PROJECT WIZARD, STEP 1, SELECT A DEVICE

3.2.2 Select Language Toolsuite

FIGURE 3-3: PROJECT WIZARD, STEP 3, NAME YOUR PROJECT

3.2.3 Name Your Project

FIGURE 3-4: PROJECT WIZARD, STEP 4, ADD FILES TO PROJECT

3.2.4 Add Files to Project

FIGURE 3-5: SAVE WORKSPACE WINDOW

3.3 BUILDING THE CODE

FIGURE 3-8: BUILD OPTIONS

3.3.1 Identify Assembler Include Path

3.3.2 Link for ICD 2

3.3.3 Build the Project

FIGURE 3-10: BUILD OUTPUT WINDOW

3.4 PROGRAMMING THE CHIP

3.4.1 Setup the Device Configuration

FIGURE 3-11: CONFIGURATION SETTINGS

3.4.2 Connect the MPLAB ICD 2 In-Circuit Debugger

3.4.3 Enable MPLAB ICD 2 Connection

FIGURE 3-14: SETTING PROGRAM MEMORY SIZE

3.4.4 Program the dsPIC30F2020

FIGURE 3-15: PROGRAMMING THE DSPIC30F2020 DEVICE

3.5 DEBUGGING THE CODE

3.5.1 Display the Code

FIGURE 3-16: PROGRAM MEMORY WINDOW

3.5.2 Step the Program

FIGURE 3-17: SOURCE CODE WINDOW

FIGURE 3-18: WATCH WINDOW DISPLAY

3.5.3 Set Break Point

FIGURE 3-19: SETTING BREAKPOINT

Chapter 4. Demonstration Program Operation

4.1 DEMONSTRATION PROGRAM

FIGURE 4-1: SMPS DEMONSTRATION PROGRAM FLOW CHART

4.2 DEMONSTRATION CODE

4.2.1 System Initialization

4.2.2 Fault Check

4.2.3 Soft Start

4.2.4 ADC Interrupt

4.2.5 System Idle Loop

4.3 OTHER CODE EXAMPLES

FIGURE A-1: dsPICDEM™ SMPS BUCK DEVELOPMENT BOARD LAYOUT

FIGURE A-2: dsPICDEM™ SMPS BUCK DEVELOPMENT BOARD SCHEMATIC 1 OF 3

FIGURE A-3: dsPICDEM™ SMPS BUCK DEVELOPMENT BOARD SCHEMATIC 2 OF 3