SLOS879B April   2014  – September 2016 DRV2625


  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  6. Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 Switching Characteristics
    8. 6.8 Typical Characteristics
  7. Parameter Measurement Information
    1. 7.1 Test Setup for Graphs
      1. 7.1.1 Default Test Conditions
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Support for ERM and LRA Actuators
      2. 8.3.2  Smart-Loop Architecture
        1. Auto-Resonance Engine for LRA
        2. Real-Time Resonance-Frequency Reporting for LRA
        3. Automatic Switch to Open-Loop for LRA
        4. Automatic Overdrive and Braking
          1. Startup Boost
          2. Brake Factor
        5. Automatic Level Calibration
          1. Automatic Compensation for Resistive Losses
          2. Automatic Back-EMF Normalization
          3. Calibration Time Adjustment
          4. Loop-Gain Control
          5. Back-EMF Gain Control
        6. Actuator Diagnostics
        7. Automatic Re-Synchronization
      3. 8.3.3  Open-Loop Operation
        1. Waveform Shape Selection for LRA
        2. Automatic Braking in Open Loop
      4. 8.3.4  Flexible Front-End Interface
        1. Internal Memory Interface
          1. Library Parameterization
          2. Playback Interval
          3. Waveform Sequencer
        2. Real-Time Playback (RTP) Interface
        3. Process Trigger
      5. 8.3.5  Noise Gate Control
      6. 8.3.6  Edge Rate Control
      7. 8.3.7  Constant Vibration Strength
      8. 8.3.8  Battery Voltage Reporting
      9. 8.3.9  Ultra Low-Power Shutdown
      10. 8.3.10 Automatic Go-To-Stand-by (Low Power)
      11. 8.3.11 I2C Watchdog Timer
      12. 8.3.12 Device Protection
        1. Thermal Sensor
        2. Over-Current Protection
        3. VDD UVLO Protection
        4. Brownout Protection
      13. 8.3.13 POR
      14. 8.3.14 Silicon Revision Control
      15. 8.3.15 Support for LRA and ERM Actuators
      16. 8.3.16 Multi-Purpose Pin Functionality
        1. Trigger-Pulse Functionality
        2. Trigger-Level (Enable) Functionality
        3. Interrupt Functionality
      17. 8.3.17 Automatic Transition to Standby State
      18. 8.3.18 Automatic Brake into Standby
      19. 8.3.19 Battery Monitoring and Power Preservation
    4. 8.4 Device Functional Modes
      1. 8.4.1 Power States
      2. 8.4.2 Operation With VDD < 2.5 V (Minimum VDD)
      3. 8.4.3 Operation With VDD > 6 V (Absolute Maximum VDD)
      4. 8.4.4 Operation in Shutdown State
      5. 8.4.5 Operation in STANDBY State
      6. 8.4.6 Operation in ACTIVE State
      7. 8.4.7 Changing Modes of Operation
    5. 8.5 Operation During Exceptional Conditions
      1. 8.5.1 Operation With No Actuator Attached
      2. 8.5.2 Operation With a Non-Moving Actuator Attached
      3. 8.5.3 Operation With a Short at REG Pin
      4. 8.5.4 Operation With a Short at OUT+, OUT-, or Both
    6. 8.6 Programming
      1. 8.6.1 Auto-Resonance Engine Programming for the LRA
        1. Drive-Time Programming
        2. Current-Dissipation Time Programming
        3. Blanking Time Programming
        4. Zero-Crossing Detect-Time Programming
      2. 8.6.2 Automatic-Level Calibration Programming
        1. Rated Voltage Programming
        2. Overdrive Voltage-Clamp Programming
      3. 8.6.3 I2C Interface
        1. TI Haptic Broadcast Mode
        2. I2C Communication Availability
        3. General I2C Operation
        4. Single-Byte and Multiple-Byte Transfers
        5. Single-Byte Write
        6. Multiple-Byte Write and Incremental Multiple-Byte Write
        7. Single-Byte Read
        8. Multiple-Byte Read
      4. 8.6.4 Programming for Open-Loop Operation
        1. Programming for ERM Open-Loop Operation
        2. Programming for LRA Open-Loop Operation
      5. 8.6.5 Programming for Closed-Loop Operation
      6. 8.6.6 Diagnostics Routine
      7. 8.6.7 Calibration Routine
      8. 8.6.8 Waveform Playback Programming
        1. Data Formats for Waveform Playback
        2. Open-Loop Mode
        3. Closed-Loop Mode
      9. 8.6.9 Waveform Setup and Playback
        1. Waveform Playback Using RTP Mode
        2. Waveform Sequencer
        3. Waveform Playback Triggers
          1. Playback Trigger Without Automatic Brake into Standby
            1. Playback Trigger With Automatic Brake into Standby (SimpleDrive)
    7. 8.7 Register Map
      1. 8.7.1  Address: 0x00
      2. 8.7.2  Address: 0x01
      3. 8.7.3  Address: 0x02
      4. 8.7.4  Address: 0x03
      5. 8.7.5  Address: 0x04
      6. 8.7.6  Address: 0x05
      7. 8.7.7  Address: 0x06
      8. 8.7.8  Address: 0x07
      9. 8.7.9  Address: 0x08
      10. 8.7.10 Address: 0x09
      11. 8.7.11 Address: 0x0A
      12. 8.7.12 Address: 0x0B
      13. 8.7.13 Address: 0x0C
      14. 8.7.14 Address: 0x0D
      15. 8.7.15 Address: 0x0E
      16. 8.7.16 Address: 0x0F
      17. 8.7.17 Address: 0x10
      18. 8.7.18 Address: 0x11
      19. 8.7.19 Address: 0x12
      20. 8.7.20 Address: 0x13
      21. 8.7.21 Address: 0x14
      22. 8.7.22 Address: 0x15
      23. 8.7.23 Address: 0x16
      24. 8.7.24 Address: 0x17
      25. 8.7.25 Address: 0x18
      26. 8.7.26 Address: 0x19
      27. 8.7.27 Address: 0x1A
      28. 8.7.28 Address: 0x1B
      29. 8.7.29 Address: 0x1C
      30. 8.7.30 Address: 0x1D
      31. 8.7.31 Address: 0x1F
      32. 8.7.32 Address: 0x20
      33. 8.7.33 Address: 0x21
      34. 8.7.34 Address: 0x22
      35. 8.7.35 Address: 0x23
      36. 8.7.36 Address: 0x24
      37. 8.7.37 Address: 0x25
      38. 8.7.38 Address: 0x26
      39. 8.7.39 Address: 0x27
      40. 8.7.40 Address: 0x28
      41. 8.7.41 Address: 0x29
      42. 8.7.42 Address: 0x2A
      43. 8.7.43 Address: 0x2C
      44. 8.7.44 Address: 0x2E
      45. 8.7.45 Address: 0x2F
      46. 8.7.46 Address: 0x30
  9. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. Actuator Selection
          1. Eccentric Rotating-Mass Motors (ERM)
          2. Linear Resonance Actuators (LRA)
            1. Auto-Resonance Engine for LRA
        2. Capacitor Selection
        3. Interface Selection
        4. Power Supply Selection
      3. 9.2.3 Application Curves
    3. 9.3 Initialization Set Up
      1. 9.3.1 Initialization Procedure
      2. 9.3.2 Typical Usage Examples
        1. Play a Waveform or Waveform Sequence from the ROM Waveform Memory
        2. Play a Real-Time Playback (RTP) Waveform
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Examples
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Waveform Library Effects List
    2. 12.2 Trademarks
    3. 12.3 Electrostatic Discharge Caution
    4. 12.4 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • YFF|9
Thermal pad, mechanical data (Package|Pins)
Orderable Information

9 Application and Implementation


Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI’s customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality.

9.1 Application Information

The typical application for a haptic driver is in a touch-enabled system that already has an application processor which makes the decision on when to execute haptic effects.

The DRV2625 device can be used fully with I2C communications (either using RTP or the memory interface). A system designer can chose to use external triggers to play low-latency effects (such as from a physical button). Figure 88 and Figure 89 show typical haptic system implementations. The system designer should not use the internal regulator (REG) to power any external load.

DRV2625 appsSchGen1_slos879.gif Figure 88. I2C Control with Optional External Trigger
DRV2625 appsSchGen2_slos879.gif Figure 89. I2C Control with Optional Interrupt Pin

Table 50. Recommended External Components

C(VDD) Input capacitor Capacitance 0.1 µF
C(REG) Regulator capacitor Capacitance 0.1 µF
R(PU) Pull-up resistor Resistance 2.2 kΩ

9.2 Typical Application

A typical application of the DRV2625 device is in a system that has external buttons which fire different haptic effects when pressed. Figure 90, Figure 91 and Figure 92 show typical schematics of such a system. The buttons can be physical buttons, capacitive-touch buttons, or GPIO signals coming from the touch-screen system.

Effects in this type of system are programmable.

DRV2625 sysSch_TrigGND_slos879.gif Figure 90. Typical Application Schematic Without External Trigger or Interrupt Pin
DRV2625 sysSch_Trig_slos879.gif Figure 91. Typical Application Schematic With External Trigger
DRV2625 sysSch_Intz_slos879.gif Figure 92. Typical Application Schematic With Interrupt Pin

9.2.1 Design Requirements

For this design example, use the values listed in Table 51 as the input parameters.

Table 51. Design Parameters

Interface I2C, external trigger
Actuator type LRA, ERM
Input power source Li-ion/Li-polymer, 5-V boost

9.2.2 Detailed Design Procedure Actuator Selection

The actuator decision is based on many factors including cost, form factor, vibration strength, power-consumption requirements, haptic sharpness requirements, reliability, and audible noise performance. The actuator selection is one of the most important design considerations of a haptic system and therefore the actuator should be the first component to consider when designing the system. The following sections list the basics of ERM and LRA actuators. Eccentric Rotating-Mass Motors (ERM)

Eccentric rotating-mass motors (ERMs) are typically DC-controlled motors of the bar or coin type. ERMs can be driven in the clockwise direction or counter-clockwise direction depending on the polarity of voltage across the two pins. Bidirectional drive is made possible in a single-supply system by differential outputs that are capable of sourcing and sinking current. This feature helps eliminate long vibration tails which are undesirable in haptic feedback systems.

DRV2625 motor_drv_slos879.gif Figure 93. Motor Spin Direction in ERM Motors

Another common approach to driving DC motors is the concept of overdrive voltage. To overcome the inertia of the mass of the motor, these motors are often overdriven for a short amount of time before returning to the rated voltage of the motor to sustain the rotation of the motor. Overdrive is also used to stop (or brake) a motor quickly. Refer the data sheet of the motor for safe and reliable overdrive voltage and duration. Linear Resonance Actuators (LRA)

Linear resonant actuators (LRAs) vibrate optimally at the resonant frequency. LRAs have a high-Q frequency response because of a rapid drop in vibration performance at the offsets of 3 to 5 Hz from the resonant frequency. Many factors also cause a shift or drift in the resonant frequency of the actuator such as temperature, aging, the mass of the product to which the LRA is mounted, and in the case of a portable product, the manner in which the product is held. Furthermore, as the actuator is driven to the maximum allowed voltage, many LRAs will shift several hertz in frequency because of mechanical compression. All of these factors make a real-time tracking auto-resonant algorithm critical when driving LRA to achieve consistent, optimized performance.

DRV2625 typ_LRA_resp_slos879.gif Figure 94. Typical LRA Response Auto-Resonance Engine for LRA

The DRV2625 auto-resonance engine tracks the resonant frequency of an LRA in real time effectively locking into the resonance frequency after half a cycle. If the resonant frequency shifts in the middle of a waveform for any reason, the engine tracks the frequency from cycle to cycle. The auto resonance engine accomplishes the tracking by constantly monitoring the back-EMF of the actuator. Note that the auto resonance engine is not affected by the auto-calibration process which is only used for level calibration. No calibration is required for the auto resonance engine. Capacitor Selection

The DRV2625 device has a switching output stage which pulls transient currents through the VDD pin. Placing a 0.1-µF low equivalent-series-resistance (ESR) supply-bypass capacitor of the X5R or X7R type near the VDD supply pin is recommended for proper operation of the output driver and the digital portion of the device. Place a 0.1-µF X5R or X7R-type capacitor from the REG pin to ground. Interface Selection

The DRV2625 device was designed with a default configuration that supports a wide variety of LRA actuators. If an actuator compatible with the default of the device is selected, then the SimpleDrive can be used without the use of I2C interface. For this case, the user has 3 options available: controlling the NRST and TRIG/INTZ pin independently (4 pin interface: VDD, GND, NRST, TRIG/INTZ), shorting NRST with TRIG/INTZ pin and controlling them with a single GPIO (3 pin interface: VDD, GND, TRIG), or shorting NRST, TRIG/INTZ and VDD together (2 pin interface: VDD, GND). Note that for the 2-pin interface, the VDD signal must ramp faster than the startup time (about 500 µs) otherwise a UVLO condition will be detected which will prevent the device from playing the desired waveform

The I2C interface is required to configure the device. The device can be used fully with this interface with either RTP or internal memory. The advantage of using this interface is that no additional GPIO (for the TRIG/INTZ pin) is required for firing effects. Therefore the TRIG/INTZ pin can be connected to GND. Using the external trigger pin has the advantage that no I2C transaction is required to fire the pre-loaded effect, which is a good choice for interfacing with a button. Power Supply Selection

The DRV2625 device supports a wide range of voltages in the input. Ensuring that the battery voltage is high enough to support the desired vibration strength with the selected actuator is an important design consideration. The typical application uses Li-ion or Li-polymer batteries which provide enough voltage headroom to drive most common actuators.

If very strong vibrations are desired, a boost converter can be placed between the power supply and the VDD pin to provide a constant voltage with a healthy headroom (5-V rails are common in some systems) which is particularly true if 2 AA batteries in series are being used to power the system.

9.2.3 Application Curves

DRV2625 Fig13_RTP_CL_Sinewave.png Figure 95. LRA SimpleDrive
DRV2625 Fig10_ERM_OL_Click_with_Autobrake.png Figure 96. ERM Open-Loop Drive with Automatic Brake

9.3 Initialization Set Up

9.3.1 Initialization Procedure

  1. After power-up, wait at least 1 ms before the DRV2625 device accepts I2C commands.
  2. Assert the NRST pin (logic high). The NRST pin can be asserted any time during or after the wait period.
  3. Write the MODE parameter (address 0x01) to value 0x00 to remove the device from standby mode.
  4. Run auto-calibration to configure the DRV2625 device for the desired actuator. Alternatively, rewrite the results from a previous calibration.
  5. If using the embedded ROM library, write the library selection bit (LIB_SEL)to select a library.


The DRV2625 device defaults to closed-loop mode with external trigger option selected in the level (enable) configuration and in RTP mode. To use other modes and features, refer to the regiter map.

9.3.2 Typical Usage Examples Play a Waveform or Waveform Sequence from the ROM Waveform Memory

  1. Initialize the device as listed in the Initialization Procedure section.
  2. Select the desired TRIG/INTZ pin function by changing the TRIG_PIN_FUNC parameter.
  3. Identify the waveform index to be played and populate the waveform sequencer.
  4. Trigger the waveform using the desired trigger method (GO bit, or external trigger). Note that if using the interrupt functionality, only the GO bit can be used to trigger the process.
  5. Device will automatically go into standby upon completion of the playback Play a Real-Time Playback (RTP) Waveform

  1. Initialize the device as shown in the Initialization Procedure section.
  2. Write the desired drive amplitude to the real-time playback input register RTP_INPUT[7:0].
  3. Trigger the waveform using the desired trigger method (GO bit, or external trigger). Note that if using the interrupt functionality, only the GO bit can be used to trigger the process.
  4. Continue writing to the RTP_INPUT[7:0] if/when desired to achieve the desired haptic effect.
  5. Send a stop trigger using the desired trigger method (GO bit, or external trigger). Note that if using the interrupt functionality, only the GO bit can be used to trigger the process.
  6. Device will automatically go into standby upon completion of the playback