Datasheet

DRV2605

SLOS825C –DECEMBER 2012 –REVISED SEPTEMBER 2014

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7.3.6 Edge Rate Control

The DRV2605 output driver implements edge rate control (ERC). This control ensures that the rise and fall

characteristics of the output drivers do not emit levels of radiation that could interfere with other circuitry common

in mobile and portable platforms. Because of ERC most system do not require external output filters, capacitors,

or ferrites beads.

7.3.7 Constant Vibration Strength

The DRV2605 PWM input uses a digital level-shifter. Therefore, as long as the input voltage meets the V

and

levels, the vibration strength remains the same even if the digital levels vary. The DRV2605 device also

features power-supply feedback. If the supply voltage drifts over time (because of battery discharge, for

example), the vibration strength remains the same as long as enough supply voltage is available to sustain the

required output voltage.

7.3.8 Battery Voltage Reporting

During playback, the DRV2605 device provides real-time voltage measurement of the V

pin. The VBAT[7:0] bit

located in register 0x21 provides this information.

7.3.9 One-Time Programmable (OTP) Memory for Configuration

The DRV2605 device contains nonvolatile, on-chip, OTP memory for specific configuration parameters. When

written, the DRV2605 device retains the device settings in registers 0x16 through 0x1A including after power

cycling. This retention allows the user to account for small variations in actuator manufacturing from unit to unit

as well as to shorten the device-initialization process for device-specific parameters such as actuator type,

actuator-rated voltage, and other parameters. An additional benefit of OTP is that the DRV2605 memory can be

customized at the device-test level without driving changes in the device software.

7.3.10 Low-Power Standby

Setting the device to standby reduces the idle power consumption without resetting the registers. In this mode,

the DRV2605 device features a fast turnon time when it is requested to play a waveform.

7.3.11 Device Protection

7.3.11.1 Thermal Protection

The DRV2605 device has thermal protection that causes the device to shut down if it becomes too hot. In the

event where the thermal protection kicks in, the DRV2605 device asserts a flag (bit OVER_TEMP in register

0x00) to notify the host processor.

7.3.11.2 Overcurrent Protection of the Actuator

If the impedance at the output pin of the DRV2605 device is too low, the device latches the over-current flag

(OC_DETECT bit in register 0x00) and shuts down. The device periodically monitors the status of the short and

remains in this condition until the short is removed. When the short is removed, the DRV2605 device restarts in

the default state.

7.4 Device Functional Modes

7.4.1 Power States

The DRV2605 device has three different power states which allow for different power-consumption levels and

functions. Figure 15 shows the transition in to and out of each state.

Product Folder Links: DRV2605