ERM

Or

LRA

OUT+

OUT-

100k

100k

470 pF

470 pF

Ch1-Ch2

(Differential )

Oscilloscope

Ch1

Ch2

ERM

or

LRA

OUT+

OUT-

Ch1-Ch2

(Differential)

with Digital

Low-Pass Filter

Oscilloscope

Ch 1

Ch2

www.ti.com

MSP430 Control and Firmware

Figure 15. Measuring the DRV2603 Output with a Digital Low-pass Filter

An analog 1st order, low-pass, RC filter can also be used; however, care must be taken not to use a filter

impedance that is too low. Low filter impedance can affect the back-EMF of the actuator and interfere with

the auto-resonance detection algorithm. See the recommend values in Figure 16.

Figure 16. Measuring the DRV2603 Output Signal with an Analog Low-pass Filter

5

MSP430 Control and Firmware

The DRV2603EVM-CT is controlled by a programmable MSP430. This section contains information for

programming and controlling the board using the MSP430.

5.1

Additional Hardware Modes

Additional modes are available on the DRV2603EVM-CT that provide increased board control and

functionality. The additional modes are not available in “demo” mode, but can be access by switching to

“binary counting mode”. In “binary counting mode” the mode LEDs count in binary (32 modes) rather than

in “demo” mode format (only 6 modes including off).

5.1.1

Enter Binary Counting Mode

To enter “binary counting mode” and access the additional modes:

1. Press and hold the increment mode button (“+”) for approximately 3 seconds.

2. Release the button when the actuator buzzes and the mode LEDs flash.

3. Select from the “binary counting modes” using the “+” and “-“ buttons.

All modes, including “demo” modes, are available in binary counting mode, see Table 3 for a description.

5.1.2

Exit Binary Counting Mode

To exit “binary counting mode” and return to “demo” mode:

1. Press and hold the decrement mode button (“-“) for approximately 3 seconds.

2. Release the button when the actuator buzzes and mode LEDs flash.

3. Select from the “demo” modes using the “+” and “-“ buttons.

13

SLOU340A – May 2012 – Revised May 2012

DRV2603 ERM/LRA Haptic Driver Evaluation Kit

Submit Documentation Feedback

Copyright © 2012, Texas Instruments Incorporated