Datasheet
Table Of Contents
- General Description
- Key Features
- Applications
- System Diagrams
- Contents
- Figures
- Tables
- Legal
- Product Family
- 1 Terms and Definitions
- 2 Block Diagram
- 3 Pinout
- 4 Characteristics
- 5 Functional Description
- 5.1 Features Description
- Driving LRA and ERM Actuators
- Automatic LRA Resonant Frequency Tracking
- Wideband LRA Support
- I2C and PWM Input Streaming
- Low Latency I2C/GPI Wake-Up from IDLE State
- Three GPI Sequence Triggers for up to Six Independent Haptic Responses
- On-Board Waveform Memory with Amplitude, Time, and Frequency Control
- Active Acceleration and Rapid Stop for High-Fidelity Haptic Feedback
- Continuous Actuator Diagnostics and Fault Handling
- No Software Requirements with Embedded Operation
- Differential Output Drive
- Current Driven System
- Configurable EMI Suppression
- Automatic Short Circuit Protection
- Ultra-Low Power Consumption with State Retention
- Ultra-Low Latency in STANDBY State
- Supply Monitoring, Reporting, and Automatic Output Limiting
- Open- and Closed-Loop Modes
- Open-Loop Sine/Custom Wave Drive Support
- Small Solution Footprint
- Additional Features
- 5.2 Functional Modes
- 5.3 Resonant Frequency Tracking
- 5.4 Active Acceleration and Rapid Stop
- 5.5 Wideband Frequency Control
- 5.6 Device Configuration and Playback
- 5.7 Advanced Operation
- 5.7.1 Frequency Tracking
- 5.7.2 Rapid Stop
- 5.7.3 Initial Impedance Update
- 5.7.4 Amplitude PID
- 5.7.5 Wideband Operation
- 5.7.6 Custom Waveform Operation
- 5.7.7 Embedded Operation
- 5.7.8 Polarity Change Reporting for Half-Period Control in DRO Mode
- 5.7.9 Loop Filter Configuration
- 5.7.10 UVLO Threshold
- 5.7.11 Edge Rate Control
- 5.7.12 Double Output Current Range
- 5.7.13 Supply Monitoring, Reporting, and Automatic Output Limiting
- 5.7.14 BEMF Fault Limit
- 5.7.15 Increasing Impedance Detection Accuracy
- 5.7.16 Frequency Pause during Rapid Stop
- 5.7.17 Frequency Pause during Rapid Stop
- 5.7.18 Coin ERM Operation
- 5.8 Waveform Memory
- 5.9 General Data Format
- 5.10 I2C Control Interface
- 5.1 Features Description
- 6 Register Overview
- 7 Package Information
- 8 Ordering Information
- 9 Application Information
- 10 Layout Guidelines
DA7280
LRA/ERM Haptic Driver with Multiple Input Triggers,
Integrated Waveform Memory and Wideband Support
Datasheet
Revision 3.0
30-Jul-2019
CFR0011-120-00
36 of 76
© 2019 Dialog Semiconductor
5.7.6 Custom Waveform Operation
With frequency tracking, Active Acceleration, and Rapid Stop disabled, and with the additional setup
for wideband operation described in Section 5.7.5, DA7280 can be configured to drive a custom
waveform to an LRA actuator. It is important to note that here the custom waveform denotes the
actual output during a single LRA resonant period and not the overall amplitude envelope during
drive events, which is controlled as previously described in Section 5.6.5. Amplitude and frequency
data can be streamed as usual in DRO, PWM, RTWM, or ETWM modes.
The waveform output during a single resonant period comprises of 16 distinct points, see Figure 18,
where points 0 to 4 are mirrored and repeated to create, by default, a sine wave (for example, point 3
and point 5, and point 2 and point 6 have the same amplitude).
Extrapolation
point
0 1
2 3 4
5
6 7
8 9 10
11
12 13
14 15 0
Value to
output
Repeated
Points
(0 %) (37.9 %) (70.3 %) (92.2 %) (100 %) (92.2 %) (70.3 %) (37.9 %) (0 %) (-37.9 %) (-70.3 %) (-92.2 %) (-100 %) (-92.2 %) (-70.3 %) (-37.9 %) (0 %)
Figure 18: Custom Wave Point Numbering
Point 0 is corresponds to an amplitude of 0 % of the value of IMAX, point 4 corresponds to an
amplitude of 100 %, and points 1, 2, and 3 are scaled to the IMAX value by the unsigned
CUSTOM_WAVE_GEN_COEFF1, CUSTOM_WAVE_GEN_COEFF2, and
CUSTOM_WAVE_GEN_COEFF3 coefficient values. The default coefficients are set to correspond to
a sine wave but can be updated to recreate any required waveform that is built of four symmetrical
sections, see Figure 18.
Table 14 contains a summary of the default coefficients and their settings.
Table 14: Default CUSTOM_WAVE_GEN_COEFFx Settings
Point
% of IMAX[4:0]
Corresponding Bits
0
0
-
1
37.9
CUSTOM_WAVE_GEN_COEFF1
2
70.3
CUSTOM_WAVE_GEN_COEFF2
3
92.2
CUSTOM_WAVE_GEN_COEFF3
4
100
-