Stellaris® Brushed DC Motor Control Reference Design
Contents
1. Item Ref Qty Part Number Description Mfg Supplier Stock No 36 U5 1 PQ1LA333MSPQ IC Voltage regula Sharp Mouser 852 tor 3 3V 500mA PQ1LA333MSPQ SOT89 5 37 U6 U7 2 FAN5109BMX IC Half Bridge Gate Fairchild Arrow FAN5109BMX Driver SO 8 38 U8 1 FAN41741S5X_NL IC Op amp Rail to Fairchild Arrow FAN41741S5X Rail SOT 23 39 Y1 1 NX5032GA Crystal 16 00MHz NDK Digikey 644 1037 2 ND 16 000000MHZ 5 0x3 2mm SMT 40 Z 1 8902 LED standoff plastic Keystone Mouser 534 8902 0 16 for LED D1 41 Z 1 BD BDC B2 PCB FR 406 2 layer Advanced Advanced BD BDC B2 3 375 x3 500 2 07 finished 116 Final Assembly Item Ref Qty Part Number Description Mfg Supplier Stock No F1 1 412 FH Fan 12VDC EBM EBM Direct 412 FH KDE1204PFV2 11 MS 40x40x10mm 7CFM Sunon Digikey 259 1351 ND A GN w 2 lead w Molex Sherlock connector F2 1 LM 0608 01 Enclosure ABS Cypress Cypress LM 0608 01 plastic 3 pieces F3 4 90380A110 Screw 4 x 0 500 McMaster McMaster 90380A110 plastite for fan F4 4 90380A108 Screw 4 x 0 375 McMaster McMaster 90380A108 plastite for enclo sure 50 January 6 2010 IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries TI reserve the right to make corrections modifications enhancements improvements and other changes to its products and services at any time and to discontinue any product or service without notice Customers s2. Clocking for the LM3S2616 is facilitated by a 16 MHz crystal Although the LM3S2616 can operate at up to 50 MHz in order to minimize power consumption the PLL is not enabled in this design The 32 bit Cortex M3 core has ample processing power to support all features including 1 Mbits s CAN with a clock speed of 16 MHz Debugging The microcontroller supports JTAG and SWD debugging as well as SWO trace capabilities To minimize board area the MDL BDC uses a 0 050 pitch header footprint which matches ARM s fine pitch definition Figure 5 2 The connections are located on the bottom of the module under the serial number label The module included in the reference design kit has a header installed however the standard MDL BDC available as a separate item does not have the header installed Some in circuit debuggers provide a matching connector Other ARM debuggers can be used with the adapter board included in the RDK Figure 5 2 MDL BDC JTAG SWD Connector 1 2 3 3V TMS SWDIO GND TCK SWCLK GND TDO OG TDI GND oe SRSTn 910 Figure 5 2 shows the pin assignments for the JTAG SWD connector as viewed from the bottom connector side of the circuit board CAN Communication 36 A key feature of the LM3S2616 microcontroller is its CAN module that enables highly reliable communications at up to 1 Mbits s The MDL BDC control board adds a standard CAN transceiver U2 additional ESD protection D
3. Install LM Flash Programmer LM Flash Programmer is a Windows GUI or command line application for programming Stellaris microcontrollers using a variety of interfaces Install and run the LM Flash Programmer on a Windows PC Step Three Configure LM Flash Programmer for Serial Transfer Select the Configuration tab and from the Quick Set drop down select Manual Configuration see Figure 4 2 Then select Serial UART Interface in the Interface drop down menu Next select the COM Port assigned by Windows to the console board This can be identified using the Windows Device Manager Finally verify that the baud rate is 115200 and then click the checkbox to Disable Auto Baud Support Figure 4 2 LM Flash Programmer Configuration Step Four Program the Console with the MDL BDC firmware 30 Select the Program tab see Figure 4 3 Then Browse to select the new binary file to download The Program Address Offset is ignored by the console Click on the Program button to start the transfer The BDC CAN console automatically jumps to the Firmware Update panel when the transfer is initiated Progress bars appear on the console display and the LM Flash Programmer window January 6 2010 Stellaris Brushed DC Motor Control User s Manual Figure 4 3 Transfer in Progress When programming completes the MDL BDC firmware is resident in the console s Flash memory If an MDL BDC with the currently selected CAN ID is connect
4. PWM frequency Two options for Speed control Industry standard R C servo type PWM interface Controller Area Network CAN interface CAN communication Multicast shared serial bus for connecting systems in electromagnetically noisy environments 1 Mbits s bit rate CAN protocol version 2 0 A B Full configurability of module options Real time monitoring of current voltage speed and other parameters Status LED indicates Run Direction and Fault conditions Motor brake coast selector Limit switch inputs for forward and reverse directions Quadrature encoder input Index input 5 V supply output to encoder Analog input Accepts 10k potentiometer or 0 3 V input Screw terminals for all power wiring Headers 0 1 inch pitch for all control signals For detailed specifications including electrical parameters see the MDL BDC data sheet January 6 2010 Stellaris Brushed DC Motor Control User s Manual Figure 1 2 MDL BDC Module Key Features top view 2 AN Il Il 1 5 i 4 Motor terminals NE ne chi ci Reference Design Kit Contents The RDK BDC contains everything needed to evaluate 12 V brushed DC motor control The RDK BDC includes MDL BDC motor control module Suitable for motors up to 12 V 40 A Uses a Stellaris LM3S2616 microcontroller Mabuchi RS 555PH 3255 Brushed DC Motor 5000 RPM 12 V JA Uni
5. blows directly on the TO 220 MOSFETs which are arranged radially around the DC bus capacitor A plastic ring encompasses the MOSFETs which provide mechanical support and ensures that the tabs do not touch The gate drivers provide up to 2 Amps of peak current to rapidly switch the gates of the MOSFETs when directed by the microcontroller s PWM module The gate drivers are designed for high voltage operation but work equally well in this 12 V application In a variation from their typical use the PWM signal is applied to the Enable ODn input to modulate either the high or low side MOSFETs A general purpose output signal from the microcontroller controls the gate driver s PWM input which selects whether it is the high or low side that is being controlled by the microcontroller s PWM signal In this configuration dead time the delay between switching states on one half of an H bridge is only an issue when changing from forward direction to reverse direction January 6 2010 37 Hardware Description Because the high side MOSFETs are N Channel types a positive Vgs is required to switch them on The gate drivers use a simple boot strapping technique to ensure that the high side Vgs remains above the Vgs on threshold Whenever the low side MOSFETs are on the associated boot strap capacitor C24 or C23 charges to 12 V through the resistor diode network Later when the high side MOSFETs turn on the boot strap capacitor maintains power to t
6. the PID control loop D the differential value of the PID control loop Ref specifies whether a potentiometer or an encoder is used as positional feedback The characteristics of the potentiometer or encoder are specified on the Configuration panel The bottom portion of the panel provides the current motor controller and limit switch status and have the same function as the Voltage Control Mode panel Configuration The Configuration panel provides the ability for the operator to specify characteristics of the attached devices in addition to specifying some operational limits There are six parameters that can be adjusted on this panel the ID encoder lines potentiometer turns brake coast override soft limit switch characteristics and the maximum output voltage ID selects the motor controller to which the parameters are applied January 6 2010 27 BDC Can Console Encoder lines specifies the number of encoder pulses received over one complete revolution of the encoder The encoder lines are used for Speed and Position control modes Pot turns specifies the number of turns of the potentiometer to travel the full range The number of potentiometer turns is used for Position control modes Brake coast specifies whether the neutral action of the motor controller is defined by the jumper setting or is overridden by the console to brake or coast Soft limit allows the definition of a software defined positional limit withou
7. 2 and connectors The pin assignments for the RJ11 RJ14 6P 4C connectors are defined in CAN in Automation CiA DS102 Figure 5 3 shows the network connector pin assignments January 6 2010 Stellaris Brushed DC Motor Control User s Manual Figure 5 3 Network Connector Pin Assignments CANH CANL V GND CAN Socket Viewed from Top Tab down The V signal Pin 2 is not used in the MDL BDC however it is passed through to support other devices that either provide or use power from this terminal The typical application for V is in providing a small amount of power to optocouplers for isolating CAN signals Other Interfaces Several other interfaces are provided on 0 1 pin headers The connections to the microcontroller are ESD protected and in most cases have 10k pull up resistors The analog input has a 0 to 3V span In order to use a 10 k potentiometer a 1k padding resistor is provided on J4 1 to drop 300 mV from the 3 3 V rail when the potentiometer is connected Output Stage and Power Supplies Page 2 Page 2 of the schematics details the power supplies gate drivers output transistors sensing and fan control circuits Motor Output Stage The motor output stage consists of an H bridge with High Low side gate drivers Each leg of the H bridge has three paralleled MOSFETs The MOSFETs are connected in parallel to reduce Rds on to about 1 8 m and to provide additional surface area for fan cooling The fan
8. CAN control Default Parameters The MDL BDC parameters have the following default values Parameters can be modified using CAN commands or by modifying the software source code Parameters modified using CAN commands are volatile and must be reloaded if the power is cycled Table 2 4 lists the factory default configuration of the MDL BDC For additional information on parameters see the January 6 2010 17 Using the Reference Design Kit Figure 2 2 Basic wiring with a Servo style speed command for open loop motor control 18 January 6 2010 Stellaris Brushed DC Motor Control User s Manual Figure 2 3 shows an advanced wiring configuration using the CAN interface Wiring for position sensing using both a position potentiometer and a quadrature encoder is detailed Although two sensor types are shown the MDL BDC software supports control and monitoring of only one sensor at a time Figure 2 3 Wiring diagram showing CAN based control for closed loop motor control January 6 2010 19 Using the Reference Design Kit Mechanical Drawing Figure 2 4 shows the MDL BDC s physical dimensions The module has two 0 175 4 5 mm diameter mounting holes as indicated Figure 2 4 MDL BDC Mechanical Drawing SETS E Di SOE E na Hane a SS Important The MDL BDC should be mounted so that the vents in the top and sides of the module are not restricted in any way A clearance of Le inch should be maintained around the
9. Copyright Copyright 2008 2010 Texas Instruments Inc All rights reserved Stellaris and StellarisWare are registered trademarks of Texas Instruments ARM and Thumb are registered trademarks and Cortex is a trademark of ARM Limited Other names and brands may be claimed as the property of others Texas Instruments 108 Wild Basin Suite 350 Austin TX 78746 http www ti com stellaris _ Cortex POWERED 2 January 6 2010 Stellaris Brushed DC Moto Microcontroller CAN and I O Interfaces Page 1 35 Output Stage and Power Supplies Page 21 37 Chapter 6 Troubleshooting rrrnavrnnnnnvnnnnvnnnnnnnnnnnvnnnnnnnnnnnnnnnnnvnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnennnnnnnnnnnnnnnnnnnnnne 39 AppendixA Schematicsaaudns rse ei 41 Appendix B Board Drawing s eennnnnnnvnvnnnnnnnvnnnnnnnnnvvnnnnnnnnvennnnnnnnnennnnnnnnnennnnnnnneennnnnnnnnnnnnnnnnnnennnnnnenennnnnnnennnnnnnn 45 Appendix C Bill of Materials BOM inn 47 4 January 6 2010 Stellaris Brushed DC Motor Control User s Manual List of Figures Figure 1 1 Brushed DC Motor Control Module ii 9 Figure 1 2 MDL BDC Module Key Features top view 11 Figure 2 1 MDL BDC s Servo PWM Input Stage i 16 Figure 2 2 Basic wiring with a Servo style speed command for open loop motor control 18 Figure 2 3 Wiring diagram showing CAN based control for close
10. P1 00KCTR ND R23 R34 0805 48 January 6 2010 Stellaris Brushed DC Motor Control User s Manual Table C 1 RDK BDC Bill of Materials Continued Item Ref Qty Part Number Description Mfg Supplier Stock No 23 R3 R4 R8 16 Resistor 10 0K 1 Panasonic Digikey P10 0KCTR ND R9 R10 0805 R11 R12 R13 R14 R20 R21 R22 R27 R33 R39 R41 24 R35 1 Resistor 0 0005 Stackpole Digikey CSNL20 00051 RT Ohms 2W 1 2512 R ND 25 R19 R32 3 Resistor 390K 1 Vishay Digikey 541 390KCRTR ND R40 0805 26 R43 1 Resistor 470K 1 Panasonic Digikey P470KCTR ND 0805 27 SWI1 1 B3S 1000P Switch Momentary Omron Arrow SW415 ND Tact 160gmf 6mm Future 28 T1 1 7701 2 Terminal Screw Keystone Bisco 7701 2 Vertical 15A Red Screw 29 T2 1 7701 3 Terminal Screw Keystone Bisco 7701 3 Vertical 15A Black Screw 30 T4 1 7701 4 Terminal Screw Keystone Bisco 7701 4 Vertical 15A White Screw 31 T3 1 7701 6 Terminal Screw Keystone Bisco 7701 6 Vertical 15A Green Screw 32 Ul 1 LM3S2616 IC Microcontroller Tl Tl LM3S2616 Stellaris Cortex M3 64 TQFP 33 U2 1 SN65HVD1050D IC CAN Transceiver Tl Arrow 296 19416 5 ND SO 8 Digikey 34 U3 1 H11L1SR2VM IC Optocoupler Fairchild Arrow H11L1SR2VM H11L1SR2M Schmitt Trigger H11L1SR2M SMD 8 35 U4 1 PQ1LA503MSPQ IC Voltage regula Sharp Mouser 852 tor 5 0V 500mA PQ1LA503MSPQ SOT89 5 January 6 2010 49 Table C 1 RDK BDC Bill of Materials Continued
11. and allows the operator to change the current value in one step The text color of the current value changes from white to black to indicate that a deferred update is active Pressing the select button again sends the final current value to the motor controller creating a step function P the proportional value of the PID control loop I the integral value of the PID control loop D the differential value of the PID control loop The bottom portion of the panel provides the current motor controller and limit switch status and have the same function as the Voltage Control Mode panel Speed Control Mode 26 The Speed Control mode panel allows the motor to be controlled by directly selecting the output shaft speed The speed of the motor is controlled by an internal PID loop that measures the shaft speed using an attached encoder and adjusts the voltage applied to the motor terminals Applying a negative speed results in the motor spinning in the opposite direction There are five parameters that can be adjusted on this panel the ID speed and three control loop parameters P I and D The up and down buttons are used to select the parameter to be modified and the left and right buttons are used to adjust the parameter s value The following parameters can be adjusted ID which selects the motor controller to which commands are sent If the ID is changed while the motor is running the motor will be stopped Speed which spec
12. apacitor 0 01uF 50V 5 0805 X7R LED Bi Color Red Grn 5mm Com Cathode Mfg Kemet Taiyo Yuden UCC Kemet Kemet Kingbright Supplier Mouser Digikey Digikey Mouser Mouser Digikey Mouser Stock No 80 C0805C104M5R 587 1291 1 ND 565 1066 ND 80 C0805C100J 5G 80 C0805C103J 5R 754 1235 ND 47 Table C 1 RDK BDC Bill of Materials Continued Item Ref Qty Part Number Description Mfg Supplier Stock No 12 J5 1 00806 Header 1x5 0 1 4ucon 4ucon 00806 6mm contact 3mm tail gold 13 J6 8 1 15948 Header 2x2 0 1 4ucon 4ucon 988 6mm contact 3mm tail gold 14 J7 0 M50 3500542 Connector 2x5 Harwin Mouser 855 M50 3500542 Header 1 27mm pitch OMIT 15 J9 1 35362 0210 Connector 2 Pin Molex Arrow 35362 0250 Sherlock 2mm vert header 16 JP1b J6b 3 151 8000 05734 Jumper Shunt Kobiconn Mouser 151 8000 05734 J8b 0 1 gold 4ucon 4ucon 17 Q1 Q2 12 FDP8874 Mosfet N Channel V Fairchild Arrow FDP8874 Q3 Q4 30V 114A TO 220 Q5 Q6 Q7 Q8 Q9 Q10 Q11 Q12 18 Q13 1 FDV301N Mosfet N Channel Fairchild Arrow FDV301NTR ND SOT 23 19 R1 R16 13 Resistor 100 ohms Panasonic Digikey P100ATR ND R17 R18 5 0805 R24 R25 R26 R29 R30 R31 R36 R37 R38 20 R15 R28 2 Resistor 4 7 Ohms Panasonic Digikey P4 7ATR ND 5 0603 21 R2 R5 3 Resistor 150 ohms Panasonic Digikey P150ATR ND R42 5 0805 22 R6 R7 4 Resistor 1 0K 1 Panasonic Digikey
13. asures the angular position using an attached potentiometer or encoder and adjusts the voltage applied to the motor terminals Applying a position value less than the current value results in the motor spinning in the opposite direction There are six parameters that can be adjusted on this panel the ID position three control loop parameters P I and D and the reference a potentiometer or encoder The up and down buttons are used to select the parameter to be modified and the left and right buttons are used to adjust the parameter s value The following parameters can be adjusted ID which selects the motor controller to which commands are sent If the ID is changed while the motor is running the motor will be stopped Position which specifies the motor shaft s target angular position value The output voltage of the motor controller is adjusted automatically via an internal PID control loop as measured by the reference until the motor shaft achieves the target position value If the select button is pressed changes to the position value will not be sent to the motor controller immediately and allows the operator to change the position in one step The text color of the position value changes from white to black to indicate that a deferred update is active Pressing select again sends the final position value to the motor controller creating a step function P the proportional value of the PID control loop I the integral value of
14. d loop motor control 19 Figure 2 4 MDL BDC Mechanical Drawing iii 20 Figure 2 5 MDL BDC Default Jumper Settings i 21 Figure 3 1 BDG CAN Console weise eae Ranta ie eae ie ee adie Ke 23 Figure 4 1 Diagram showing the two step firmware update Drorcessg 29 Figure 4 2 LM Flash Programmer Configuration ii 30 Figure 4 3 Transief Re el 31 Figure 4 4 Locating the JTAG 21 0 January 6 2010 5 January 6 2010 Stellaris Brushed DC Motor Control User s Manual List of Tables Table 2 1 Table 2 2 Table 2 3 Table 2 4 Mabuchi RS 555PH 3255 Motor Specifications i 14 Control Method Comparison renn nnnnnenr renn nnnnnennrennnnrnnnennennnnnnenennneennrnnesnnnnersnnnnennnnnne 15 Recommended Values for External Resistor 16 MDL BDC Factory Default Configuration 17 January 6 2010 January 6 2010 CHAPTER 1 Stellaris Brushed DC Motor Control Reference Design Kit RDK Overview The RDK BDC is a Stellaris reference design for the MDL BDC a Controller Area Network CAN based DC motor control The MDL BDC motor control module provides variable speed control for 12 V brushed DC motors at up to 40 A continuous current Features include high performance CAN networking as well as a rich set of control options and sensor interfaces including analog and quadrature encoder interfaces High fre
15. e fault V Limit Switch status Forward and Reverse Current Control Mode The Current Control mode panel allows the motor to be controlled by directly selecting the output current The torque of the motor is directly proportional to the winding current and applying a negative current in other words electronically reversing the power and ground connections results in the motor spinning in the opposite direction There are five parameters that can be adjusted on this panel the ID current and three control loop parameters P I and D The up and down buttons are used to select the parameter to be modified and the left and right buttons are used to adjust the parameter s value The following parameters can be adjusted ID which selects the motor controller to which commands are sent If the ID is changed while the motor is running the motor will be stopped Current which specifies the target winding current value The output voltage of the motor controller is adjusted automatically via an internal PID control loop until the motor draws the target current value A positive current value results in voltage being applied to the white output terminal and ground being applied to the green output terminal while a negative current value applies voltage to the green output terminal and ground to the white output terminal If the select button is pressed changes to the current value will not be sent to the motor controller immediately
16. e included in the RDK When controlling more than one MDL BDC modular cables 6P 4C or 6P 6C should be used to link the modules Suitable cables include the Digikey H2642R 07 ND cable Power for the console comes from a USB cable The CAN cable also included in the RDK has a RJ 11 6P 4C connector at one end and a 10 pin socket at the other end Connect cables as follows 1 Connect the CAN cable between the console CAN connector P1 and either NET connector on the MDL BDC 2 Use RJ11 RJ14 modular cables to daisy chain CAN communications to any other MDL BDC devices The cables should be 6 position with either 4 or 6 contacts installed Suitable cables have plugs crimped on opposite sides of the cable and are referred to as reverse or straight cables because pin 1 connects to pin 1 3 The last MDL BDC in the chain should have a CAN terminator inserted in its NET connector The BDC CAN console has an integrated termination resistor so it must be used as an end point 4 Connect the USB cable between the BDC CAN console and the USB port of a PC The console application software will then start see Figure 3 1 on page 23 5 If USB drivers were not previously installed then follow the procedure in the Quickstart guide before proceeding USB drivers are necessar January 6 2010 Stellaris Brushed DC Motor Control User s Manual Operation The direction buttons left right up and down on the left side of the BDC CAN co
17. ed the console immediately starts a firmware update over CAN The update over CAN may also be initiated manually This procedure is covered in more detail in the following section called Firmware Update Using BDC CAN Console Firmware Update Using BDC CAN Console The following steps show how to transfer the firmware image from the console into the MDL BDC During this operation the USB cable is required only as a power source to the console Step One Establish CAN connection Connect the console to the MDL BDC using the CAN cable Follow the Set Up on page 24 for step by step instructions Move to Step 2 once the console screen shows a valid CAN connection to the MDL BDC Step Two Navigation to the Firmware Update Panel Press the Up navigation switch to highlight the panel Title bar The default mode is Voltage Control Mode Press the select switch to bring up the list of panels Navigate to the Firmware Update title and press select again to move to that panel This panel allows the firmware on the MDL BDC to be updated over the CAN network A firmware image for the motor controller is first stored in the flash of the console board and then used to update the motor controller The ID of the motor controller to be updated can be selected on this panel By using the console resident firmware image multiple motor controllers can be updated one at a time using this panel without the need to download from a PC each time Ja
18. he high side driver with respect to the Motor terminal One issue with the boot strap capacitor method is that the capacitor voltage will decay to an unacceptable level unless a low side MOSFET is periodically switched on This state only occurs when the motor is running full forward or full reverse The MDL BDC software intermittently switches to the low side MOSFETs for a short duration to replenish the bootstrap capacitor The short duration has no impact on motor speed Power Supply Two cascaded voltage regulators create 5 V and 3 3 V power supply rails from the 12 V input 5 V is used only for the CAN transceiver and quadrature encoder functions The cascaded arrangement also provides a way to spread the thermal dissipation of the linear regulators with the 5 V taking most of the burden 3 3 V is used by the MCU and peripheral circuitry Current Sensing 38 The current sensing circuit consists of a low side shunt resistor R35 and a non inverting voltage amplifier Due to the high current in the bridge the shunt resistor is just 500 u January 6 2010 Troubleshooting Although the MDL BDC is simple to use simple errors in wiring software or use can affect normal operation This chapter provides guidance on resolving common problems Table 6 1 Common Problems No LED ct2moD c 33t8 9 162ctivity028 9 1 0 028 al 0 ways of 16 f 1596 Powe T JO34u January 6 2010 39 Troubleshooting 40 January 6 2010 Schema
19. hould obtain the latest relevant information before placing orders and should verify that such information is current and complete All products are sold subject to Tl s terms and conditions of sale supplied at the time of order acknowledgment TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with Tl s standard warranty Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty Except where mandated by government requirements testing of all parameters of each product is not necessarily performed TI assumes no liability for applications assistance or customer product design Customers are responsible for their products and applications using TI components To minimize the risks associated with customer products and applications customers should provide adequate design and operating safeguards TI does not warrant or represent that any license either express or implied is granted under any TI patent right copyright mask work right or other TI intellectual property right relating to any combination machine or process in which TI products or services are used Information published by TI regarding third party products or services does not constitute a license from TI to use such products or services or a warranty or endorsement thereof Use of such information may require a license from a third party under the patents or other i
20. ifies the motor shaft s target angular speed value The output voltage of the motor controller is adjusted automatically via an internal PID control loop until the motor spins at the target speed value A positive speed value results in voltage being applied to the white output terminal and ground being applied to the green output terminal while a negative speed value applies voltage to the green output terminal and ground to the white output terminal January 6 2010 Stellaris Brushed DC Motor Control User s Manual If the select button is pressed changes to the speed value will not be sent to the motor controller immediately and allows the operator to change the speed value in one step The text color of the speed value changes from white to black to indicate that a deferred update is active Pressing the select button again sends the final output speed value to the motor controller creating a step function P the proportional value of the PID control loop I the integral value of the PID control loop D the differential value of the PID control loop The bottom portion of the panel provides the current motor controller and limit switch status and have the same function as the Voltage Control Mode panel Position Control Mode The Position Control mode panel allows the motor to be controlled by directly selecting the output shaft angular position The angular position of the motor is controlled by an internal PID control loop that me
21. ign Kit rectified by the MDL BDC back into the bus capacitor As the capacitor charges the voltage at the supply terminals may increase It is important that the power supply can handle this momentary condition without entering a fault condition The power supply must also present sufficiently low impedance so that the MDL BDC s voltage rating is not exceeded A sealed lead acid battery easily meets these requirements NOTE The MDL BDC does not have reverse polarity input protection Motor Selection The MDL BDC operates 12 V brushed DC motors Typical motors include model BI802 001A from CIM and model RS 555PH 3255 from Mabuchi see Table 2 1 for motor specifications Some 14 January 6 2010 Stellaris Brushed DC Moto Using the Reference Design Kit To reset the servo style PWM input to the default factory range 1 2 3 4 5 Disconnect the power to the MDL BDC Hold down the USER switch with a straightened paperclip Reconnect power to the MDL BDC After 5 seconds the LED flashes Red and Green slowly to indicate a successful calibration reset to factory settings Release the USER switch Electrical Interface The servo PWM input is electrically isolated from other circuits using an optocoupler The MDL BDC board data sheet contains electrical specifications including common mode voltage limits for the input stage Figure 2 1 MDL BDC s Servo PWM Input Stage The on board resistor R5 has been selected to a
22. llow a signal of only a few volts to drive the optocoupler At 3 3 V or more it is advisable to add additional series resistance to limit the current into the LED The PWM input stage is essentially a current driven device so the threshold for a logic high level input is defined in milliamps Some recommended values for an external resistor are listed in Table 2 3 CAN Communication 16 January 6 2010 Stellaris Brushed DC Motor Control User s Manual USER switch on the MDL BDC informs that particular module to accept the previously specified code The CAN protocol used by the MDL BDC includes the following capabilities Firmware update over CAN Read supply voltage motor voltage temperature and current Set motor voltage or target position Set control mode to speed or position Configure parameters Enable features such as closed loop speed and position control The CAN protocol provides a number of commands and divides them into groups based on the type of command The commands are grouped according to broadcast messages system level commands motor control commands configuration commands and motor control status information The interface also provides a method to extend the network protocol to other devices by defining a CAN device encoding that takes into account device type and manufacturer See the RDK BDC Software User s Guide for complete details The RDK BDC includes a CAN board with an example application that demonstrates
23. module to aid cooling Status LED Table 2 5 lists all LED status and fault codes Fault information is prioritized so only the highest priority fault will be indicated Table 2 5 Normal Operating Conditions Solid Yellow Neutral speed set to 0 Fast Flashing Green Forward Fast Flashing Red Reverse 20 January 6 2010 Stellaris Brushed DC Motor Control User s Manual Solid Green Full speed forward Solid Red Full speed reverse Fault Conditions Slow Flashing Yellow Loss of CAN or servo link Slow Flashing Red Fault Calibration or CAN Conditions Flashing Red and Green Calibration mode active Flashing Red and Yellow Calibration mode failure Jumper Settings Figure 2 5 shows the factory default jumper settings Figure 2 5 MDL BDC Default Jumper Settings Fault Detection Software and hardware in the MDL BDC continually monitors for various fault conditions Fault Conditions A slow flashing Red LED indicates a fault condition The MDL BDC will detect and shutdown the motor if any of the following conditions are detected Power supply under voltage Over temperature January 6 2010 21 Using the Reference Design Kit Over current Limit switch activated in the current direction of motion The LED will indicate a fault state during the fault condition and for 3 seconds after the fault is cleared except for the limit switch fault which is cleared instantaneously Loss of CAN or Servo style S
24. nsole are used to navigate through the user interface The select button on the right side of the console is used to select items The user interface is divided into several panels the top line of the display always contains the name of the current panel By moving the cursor to the top line and pressing select a menu appears which allows a different panel to be displayed by pressing select again The BDC CAN console provides five operating modes Voltage Control Mode on page 25 Current Control Mode on page 26 Speed Control Mode on page 26 Position Control Mode on page 27 Configuration on page 27 The mode panels in the user interface are discussed individually in more detail below At startup the Voltage Control mode panel is displayed first Voltage Control Mode The Voltage Control mode panel allows the motor to be controlled by directly selecting the output voltage The speed of the motor is directly proportional to the voltage applied and applying a negative voltage in other words electronically reversing the power and ground connections will result in the motor spinning in the opposite direction There are three parameters that can be adjusted on this panel the ID voltage and ramp rate The up and down buttons are used to select the parameter to be modified and the left and right buttons are used to adjust the parameter s value The following parameters can be adjusted ID which selects the mo
25. ntellectual property of the third party or a license from TI under the patents or other intellectual property of TI Reproduction of TI information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties conditions limitations and notices Reproduction of this information with alteration is an unfair and deceptive
26. nuary 6 2010 31 Firmware Updates and Debugging 32 January 6 2010 Stellaris Brushed DC Motor Control User s Manual Figure 4 5 Firmware debugging using JTAG SWD Ribbon cable PC running LM Flas Utility or third party Development tools January 6 2010 10 pin to 20 pin Adapter Cable 33 Firmware Updates and Debugging 34 January 6 2010 Hardware Description The MDL BDC motor control module uses a highly integrated Stellaris LM3S2616 microcontroller to handle PWM synthesis analog sensing and the CAN interface Only a few additional ICs are necessary to complete the design The entire circuit is built on a simple two layer printed circuit board All design files are provided on the RDK CD System Description A unique aspect of the MDL BDC design is the in January 6 2010 35 Hardware Description Microcontroller At the core of the MDL BDC is a Stellaris LM3S2616 microcontroller The LM3S2616 contains a peripheral set that is optimized for networked control of motors including 6 high speed ADC channels a motor control PWM block a quadrature encoder input as well as a CAN module The microcontrollers PWM module can generate two complementary PWM signal pairs that are fed to the power stage The LM3S2616 has an internal LDO voltage regulator that supplies 2 5 V power for internal use This rail requires only three capacitors for decoupling and is not connected to any other circuits
27. peed Link A slow flashing Yellow LED indicates that the MDL BDC is not receiving a valid control signal The control link error is cleared immediately when a CAN or PWM signal is restored 22 January 6 2010 CHAPTER 3 BDC Can Console The BDC CAN console included in the RDK BDC provides a convenient way to evaluate some of the capabilities of the CAN interface Overview The BDC CAN console is based on the Stellaris LM3S2965 Evaluation Board The board ships with the console application ready to run For more information on the capabilities of this board see the LM3S2965 Evaluation Board User s Manual Note that the LM3S2110 CAN Device board is not included in the Reference Design Kit Figure 3 1 BDC CAN Console mess H g He co mm L I i ra i T The application provides a simple user interface for the brushed DC motor controller board running on the EK LM3S2965 board and communicating over CAN In addition to running the January 6 2010 23 BDC Can Console motor the motor status can be viewed the CAN network enumerated and the motor controller s firmware can be updated Using the Console Cables Set Up 24 The CD included in the RDK BDC contains a Quickstart guide that covers basic operation of the MDL BDC and console See this document for step by step instructions for connecting and using the RDK BDC Table 3 1 shows several cables that are used in conjunction with the BDC CAN console and that ar
28. quency PWM enables the DC motor to run smoothly and quietly over a wide speed range MDL BDC uses highly optimized software and a powerful 32 bit Stellaris LM3S2616 microcontroller to implement open loop speed control as well as closed loop control of speed position or motor current The Reference Design Kit RDK BDC contains an MDL BDC motor control module as well as additional hardware and software for evaluating CAN communication After evaluating the RDK BDC users may choose to either customize parts of the hardware and software design or use the MDL BDC without modification See the MDL BDC board data sheet available for download from www ti com stellaris for complete technical specifications Figure 1 1 Brushed DC Motor Control Module January 6 2010 9 Stellaris Brushed DC Motor Control Reference Design Kit RDK Overview Feature Summary The MDL BDC control board provides the following features Controls brushed 12 V DC motors up to 40 A continuous Controller Area Network CAN interface at 1 Mbit s Industry standard servo pulse width modulation PWM speed input interface Limit switch encoder and analog inputs Fully enclosed module includes fan cooling Flexible configuration options Easy to customize full source code and design files available Factory source code compiles to less than 16 KB Specification Overview 10 Key specifications of the MDL BDC include Quiet control of brushed DC motors 15 kHz
29. t the use of physical limit switches If enabled the forward and reverse limit positions and conditions may be specified Max Vout defines the maximum voltage allowed to be generated during operation This value is used during the Current Speed and Position Control modes Device List 28 This panel lists the motor controllers that reside on the CAN network All 63 possible device IDs are listed with those that are not present shown in dark gray and those that are present in bright white By moving the cursor to a particular ID and pressing the select button a device ID assignment will be performed The motor controller s will wait for five seconds after an assignment request for its button to be pressed indicating that it should accept the device ID assignment So for example if there are three motor controllers on a network the following sequence can be used to give them each unique IDs 1 Move the cursor to number 1 and press select The LED on all three motor controllers will blink January 6 2010 Firmware Updates and Debugging The MDL BDC supports two methods for updating the firmware resident in the LM3S2616 January 6 2010 29 Firmware Updates and Debugging Step One Install USB Drivers for the Console The USB driver installation is covered in the RDK BDC Quickstart Guide See that document for full details Once the USB drivers are installed the console appears as a Virtual Com port on your PC Step Two
30. tics This section contains the schematic diagrams for the RDK BDC RDK BDC MCU Network and Interface on page 42 RDK BDC Power Supplies and Input Stage on page 43 January 6 2010 41 A B elie SE S 0 01UF 0 1UF 0 1UF 44 der per 0 01UF History Description D Drawing Title Jaguar Brushed DC Motor Control Page Title MCU Network and Interface Size p Document Number are BDC Pate 10 20 2008 oe he Drawing Title Jaguar Brushed DC Motor Control Page Title Size Document Number Date 10 20 2008 Sheet Ra Rev 44 January 6 2010 January 6 2010 45 46 January 6 2010 Bill of Materials BOM Table C 1 provides the BOM for the RDK BDC Table C 1 Item Ref 1 C1 C2 C7 C8 C11 C25 2 C12 C13 C14 C16 C17 C18 C22 C23 3 C15 4 C3 C4 5 C5 C6 C9 C10 C19 C20 C21 C24 6 D1 7 D2 D3 January 6 2010 Qty 6 RDK BDC Bill of Materials Part Number C0805C104M5RACTU TMK212BJ 105KG T ESMG250ELL332MN2 OS C0805C100 5GACTU C0805C103 5RACTU WP59SRSGW CC WP59EGW Description Capacitor 0 1uF 50V 20 0805 X7R Capacitor 1 0uF 25V X5R 0805 Capacitor 3300uF 25V Electro 20x20mm Capacitor 10pF 50V 5 Ceramic NPO COG 0805 C
31. tor controller to which commands are sent If the ID is changed while the motor is running the motor will be stopped Voltage which specifies the output voltage sent from the motor controller to the motor A positive voltage will result in voltage being applied to the white output terminal and ground being applied to the green output terminal while a negative voltage will apply voltage to the green output terminal and ground to the white output terminal If the select button is pressed changes to the output voltage will not be sent to the motor controller immediately allowing the ramp to be used The text color of the voltage changes from white to black to indicate that a deferred update is active Pressing select again will send the final output voltage to the motor controller creating a step function Ramp which specifies the rate of change of the output voltage When set to none the output voltage will change immediately When set to a value the output voltage is slowly changed from the current to the target value at the specified rate This can be used to avoid browning out the power supply or to avoid over torquing the motor on startup for example preventing a loss of traction when a wheel is being driven The bottom portion of the panel provides the current motor controller status Four fault conditions are indicated Over Current fault C Over Temperature fault T January 6 2010 25 BDC Can Console Under Voltag
32. versal input wall power supply 12V1 25A Plug adaptors for US UK EU and AUST BDC CAN console Convenient tool for controlling key MDL BDC functions Integrated graphics display and navigation switches Firmware update feature Based on EK LM3S2965 Evaluation Kit January 6 2010 11 Stellaris Brushed DC Motor Control Reference Design Kit RDK Overview 12 CAN cable Connects the console to the MDL BDC CAN terminator Plug in 120 terminator USB cable Provides power and communication to the BDC CAN console Adapter cable for ARM JTAG SWD fine pitch header Texas Instruments Part ADA2 Ribbon cable for ARM JTAG SWD 20 position cable for using the BDC CAN console as a debug interface Reference design kit CD Complete documentation including Quickstart and user s guides LM Flash Programmer utility for firmware updates Complete source code schematics and PCB Gerber files The source code can be modified and compiled using any of the following tools Keil RealView Microcontroller Development Kit MDK ARM IAR Embedded Workbench Code Sourcery GCC development tools Code Red Technologies development tools Texas Instruments Code Composer Studio IDE January 6 2010 Using the Reference Design Kit This chapter provides information about the RDK BDC kit contents and on using the RDK Important Information January 6 2010 13 Using the Reference Des
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