DRV8811EVM User's Guide Literature Number: SLVA344A July 2009 – Revised September 2009
SLVA344A – July 2009 – Revised September 2009 Submit Documentation Feedback
Contents 1 Introduction......................................................................................................................... 6 1.1 Block Diagram ............................................................................................................. 6 1.2 Power Connectors 1.3 Test Stakes ................................................................................................................ 7 1.4 Jumpers ...............................................................
www.ti.com List of Figures 1 2 3 4 5 6 7 8 9 10 4 VREF SELECT Jumper ..................................................................................................... 7 DECAY SELECT Jumper ................................................................................................... 7 DRV8811_RD_EVM_R1p0.exe Main Screen ............................................................................ 8 Acknowledgement Text Box ..........................................................................
User's Guide SLVA344A – July 2009 – Revised September 2009 Laser and Motor Drives This document is provided as a supplement to the DRV8811 datasheet. It details the hardware implementation of the DRV8811 customer evaluation module (EVM).
Introduction 1 www.ti.com Introduction The DRV8811_RD customer EVM is the complete solution to evaluating the DRV8811 microstepping bipolar stepper driver. It houses a USB link to provide easy control from a PC computer, an MSP430 microcontroller that interprets serial commands from the PC and generates control signals to the driver device, and the DRV8811 device with access to all signals for a complete evaluation. 1.1 Block Diagram VM Power Motor Outputs Test Stakes DRV8811 USB 1.
Installing Drivers And Software www.ti.com 1.3 Test Stakes Every pin on the device has been brought out to a test stake. A label on the silkscreen identifies each signal. 1.4 Jumpers Three pin jumpers can be configured independently from the other two or three pin jumpers. However, two pin jumpers must either be closed or open. Two pin jumpers (JP2 to JP5) connect the diodes to the motor outputs and are used under asynchronous rectification (SR = LO).
Windows Application 2.2 www.ti.com Installing the DRV8811 Evaluation Board Windows Application Software The included CD contains a folder titled “Windows Application”. It is recommended for the contents of this folder to be copied to any desired folder on the computer. The reason for this is the Settings.ini file will be written upon software exit. This action can not take place if the application is run within the CD environment. 2.
Windows Application www.ti.com 3.1 Menu The menu at the top of the application offers a series of quick options for how the COM port is to behave. 1. File → Exit - Terminates the application 2. Settings → Port - Selects from COM1 to COM4. Default is COM4. The serial port's actual port number defaults to what we have specified on “USB_Drivers_Install_Readme.pdf”. However, any port between COM 1 and COM 4 are equally usable. 3. Connect: Opens the serial port.
Windows Application www.ti.com A checked checkbox translates to a HI level on the respective control signal. A un-checked checkbox translates to a LO level on the respective control signal. 3.3 Updating DAC Output for Current Control (VREF/DECAY) If the DRV8811 EVM has been configured to accept VREF analog voltages through the MSP430 microcontroller interface (JP1 is set to INT), then the slider bar on the Current Control frame can be used to set the VREF voltage. Figure 6.
Windows Application www.ti.com The DRV8811_RD customer EVM allows for the possibility of coordinating step rates such that accelerating and decelerating profiles are achieved. Both acceleration and deceleration are controlled by the same parameters, acceleration rate and time base. When the motor starts, it always starts at the slowed pulses per second (PPS) speed (62 pulses per second). The controller will accelerate the motor in order to reach the PPS speed.
Schematic www.ti.com Pressing the Start Steps button, will start the timer and pulses will be generated at the rate specified by the decimal number at the PPS text box. Once the Start Steps button is pressed it becomes the Stepping button. Press the Stepping button to stop the stepper motion. When the motor is stepping, the Update Speed button becomes enabled. Speed can be updated by modifying the PPS text box and then pressing the Update Speed button.
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 should obtain the latest relevant information before placing orders and should verify that such information is current and complete.
