Hardware Overview
5.8
Switches S1 and S2
S1 is connected to P0.0 on the CC2541. Switch S1 closes the connection between GND and P0.0 when it
is pressed. Even though disabled on the DRV2605EVM-BT, the switch is available to maintain
compatibility with other versions of the firmware where this port is used for pairing.
S2 is a load switch which connects and disconnects the battery. Turn S2 to ON position if using an
external battery to power the board.
5.9
OUT– and OUT+
These pads are the output of the DRV2605. A vibration motor like an ERM or LRA can be connected to
these pads.
5.10 LEDs
LEDs I to XII: These white LEDs arranged in a clock-like orientation, can display time synced from the iOS
device and demonstrate visible alerts from notification menu. Custom LED patterns can be created from
the LED Playground mode.
Status LEDS: D14 indicates that the DRV2605EVM-BT is powered by a valid source and ready to talk
over Bluetooth. D14 is intentionally made dim as it ON at all times.
5.11 Audio-to-Haptics and Trigger Mode
The DRV2605 features an audio to haptics mode that converts an audio input signal into meaningful
haptic effects using the Immersion "BOOMbox" technology. The audio signal can be connected to the
TRG pin. For the TRG pin to function as the analog audio input to the haptic driver for audio-to-haptics
mode, the resistor R39 has to be replaced with an 0402 size 0.1-µF DC blocking capacitor. Later the
driver has to be set to the audio-to-haptics mode on the I
2
C register setting. For more details on this
configuration, refer to the DRV2605 data sheet.
The trigger pin can be connected to an external microcontroller's GPIO or an interrupt line of a different IC
to fire effects on an event. The DRV2605 has to be configured to External Trigger Mode through Register
Control tab or more easily through the "Turn ON Ext. Trigger" button available at different sections of the
iOS app. for this function to be executed. An example of this function is when a Touch-IC generates an
interrupt and a haptic effect is generated to mimic a "keyboard click".
9
SLOU391 – May 2014
DRV2605EVM-BT User's Guide
Copyright © 2014, Texas Instruments Incorporated