Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsDev KitsPCB design board

Table Of Contents

CPG005_DRV88xx Evaluation Modules

User's Guide

SLVU410– April 2011

CPG005_DRV88xx Evaluation Modules

This document is provided as a supplement to the DRV8840 and DRV8842 datasheets. It details the

hardware implementation of the CPG005_DRV88xxEVM Customer Evaluation Module (EVM). On this

document, DRV88xx will be used interchangeably to refer to any of the aforementioned devices.

Contents

1 Block Diagram ............................................................................................................... 2

1.1 Power Connectors ................................................................................................. 2

1.2 Test Stakes ......................................................................................................... 2

1.3 Jumpers ............................................................................................................. 2

1.4 Motor Outputs ...................................................................................................... 3

2 Installing Drivers And Software ........................................................................................... 4

2.1 Installing the FTDI USB Driver ................................................................................... 4

2.2 Installing the CPG004_DRV88xx Evaluation Board Windows Application Software ...................... 4

2.3 Running the Windows Application Software .................................................................... 4

3 The Windows Application .................................................................................................. 4

3.1 The Menu ........................................................................................................... 7

3.2 DRV88xx GPIO Control Signals ................................................................................. 7

3.3 Updating DAC Output for Current Control (VREFA and VREFB) ........................................... 8

3.4 DC Motor Speed Control (PWM) ................................................................................. 8

4 Schematic .................................................................................................................... 9

List of Figures

1 AVREF Select Jumper Configuration .................................................................................... 3

2 DECAY Select Jumper Configuration .................................................................................... 3

3 DRV8840 Tab ............................................................................................................... 5

4 DRV8842 Tab ............................................................................................................... 6

5 GPIO Control Signals....................................................................................................... 7

6 Current Control .............................................................................................................. 8

7 PWM Control ................................................................................................................ 9

SLVU410–April 2011 CPG005_DRV88xx Evaluation Modules

Submit Documentation Feedback

Summary of content (10 pages)

PAGE 1
User's Guide SLVU410 – April 2011 CPG005_DRV88xx Evaluation Modules This document is provided as a supplement to the DRV8840 and DRV8842 datasheets. It details the hardware implementation of the CPG005_DRV88xxEVM Customer Evaluation Module (EVM). On this document, DRV88xx will be used interchangeably to refer to any of the aforementioned devices. 1 2 3 4 Contents Block Diagram ............................................................................................................... 1.
PAGE 2
Block Diagram 1 www.ti.com Block Diagram Motor Outputs VM Power AVREF DECAY DRV88xx MSP430 USB Conn USB Chip Proto Area Where DRV88xx stands for one of DRV8840 or DRV8842 1.1 Power Connectors The CPG005_DRV88xx Customer EVM offers access to VM (Motor Voltage) power rail via a terminal block (J1). A set of test clips in parallel with the terminal block allows for the monitoring of the input power rail. User must apply VM according to datasheet recommended parameters.
PAGE 3
Block Diagram www.ti.com 1.3.1 AVREF Select Jumper (JP2) From Pot From DAC 1 1 (a) (b) To configure the AVREF select jumper: (a) Use position JP2-1:2 to select the MSP430 DAC output (default). (b) Use position JP2-2:3 to select the respective variable resistance potentiometer. This jumper should not be left open as lack of reference voltage on the device will minimize current sourcing into the respective H Bridge, resulting in very poor motion or no motion at all. Figure 1.
PAGE 4
Installing Drivers And Software www.ti.com 2 Installing Drivers And Software 2.1 Installing the FTDI USB Driver Instructions on how to install the FTDI USB driver on a Windows based computer are detailed in the “USB_Drivers_Install_Readme.pdf” file supplied with the CD inside the USB_Driver folder. 2.2 Installing the CPG004_DRV88xx Evaluation Board Windows Application Software The Windows application for the CPG005 based EVM’s is the same Windows Application as for the CPG004 based EVM’s.
PAGE 5
The Windows Application www.ti.com Figure 3. DRV8840 Tab On the CPG004 DRV88xx EVM Windows Application there are two tabs usable with the CPG005 based EVMs. They are very similar and refer to the differences in the two devices, namely the ENABLE/PHASE interface and the IN1/IN2 interface. Everything else will operate in the same fashion.
PAGE 6
The Windows Application www.ti.com Figure 4. DRV8842 Tab A look at the DRV8842 tab on the CPG004 DRV88xx EVM Windows Application. This tab is virtually identical to the DRV8840 tab.
PAGE 7
The Windows Application www.ti.com 3.1 The Menu The menu at the top of the application offers a series of quick options for how the COM port is to behave. File: Exit – Terminates the application Settings: Port – Selects from COM1 to COM4. Default is COM4. The serial port's actual port number defaults to what we have specified on the “USB_Drivers_Install_Readme.pdf”. However, any port between COM 1 and COM 4 are equally usable. Connect: Opens the serial port.
PAGE 8
The Windows Application 3.2.1 www.ti.com About DECAY The DECAY pin is in reality a triple state input. The GPIO operates as HI and LO according to the checkbox. To have the DECAY pin floating, engaging mixed decay mode, simply remove the decay jumper JP3. 3.
PAGE 9
Schematic www.ti.com DRV8840 DRV8842 Figure 7. PWM Control 4 Schematic A schematic is available in the form of a PDF file (“CPG005_Schematic.pdf”) inside the EVM_Related folder on the supplied CD.
PAGE 10
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.