Datasheet

Table Of Contents
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
44 of 76
© 2019 Dialog Semiconductor
For example, assuming ACCELERATION_EN = 1, the snippet shown in Figure 25 creates a
waveform that ramps from zero to an amplitude of 1111 over a period of 2 timebases, then step from
1111 to 1000, and remains there for 4 timebases. The length (in milliseconds) of a timebase is
specified using the TIMEBASE frame bits, see Section 5.8.3.
Description
RMP
TIME[6:4]
AMP[3:0]
Ramp
1
0
0
1
1
1
1
1
Step
0
0
1
1
1
0
0
0
P1
Amplitude
Timebase
P2
1111
1000
1 2 3 4 5 6 7
Figure 25: Snippet Ramp and Step with ACCELERATION_EN = 1
If a constant drive level of longer than 8 timebases is required, set RMP = 0 for subsequent PWL
points.
A generic example of a snippet is shown in Figure 26. Pn represents the PWL pair located at
amplitude An and with time step Tn, where n represents the PWL pair number. Note that a snippet
played at the start of a non-looped sequence will start from a default point P0 set at zero amplitude;
however, if the snippet is not at the start of a sequence or is read during the looping of a sequence,
the starting point will be the last played PWL point.
P1
T1
P2
P3
P4
P5
Pn
P0
T2 T3 T4 T5 TnT0 = 0
A1
A2
A3
A4
A5
An
Amplitude
[%]
Time
Time
P1
T1
P2
P3
P4
P5
Pn
P0
T2 T3 T4 T5 TnT0 = 0
A1
A2
A3
A4
A5
An
Amplitude
[%]
P1
T1
P2
P3
P4
P5
Pn
P0
T2 T3 T4 T5 TnT0 = 0
A1
A2
A3
A4
A5
An
Amplitude
[%]
RMP = 1 for all PWL points
RMP = 0 for all PWL points
Time
Figure 26: Snippet Example
Note 1 A built-in snippet containing a single silent PWL point (amplitude = 0) is available by setting
SNP_ID = 0. The duration is set to 2 timebases. Because of the existence of this snippet, customer
defined snippets start at SNP_ID = 1. The snippet is inherent to the decoding and is not actually stored
in the waveform memory. The number of snippets (byte 0) does not include snippet 0 and there is no
end pointer for snippet 0 stored in the waveform memory.