7.4.5.2.3 Sine Waveform Generation
The sine wave function uses 24 preprogrammed points per cycle.
shows that the frequency of the
sine wave depends on the SLEW-RATE settings:
f
SINE_WAVE
=
1
24 × SLEW_RATE
(8)
where SLEW_RATE is the SLEW-RATE-X setting specified in
An external RC load with a time constant greater than the slew-rate settings can be dominant over the internal
frequency calculation. The SLEW-RATE-X setting is available in the DAC-X-FUNC-CONFIG register. Writing
0b100 to the FUNC-CONFIG-X bit field in the DAC-X-FUNC-CONFIG register selects sine wave. The codes
for the sine wave are fixed. Use the gain settings at the output amplifier for changing the full-scale output
using the internal reference option. The gain settings are accessible through the VOUT-GAIN-X bits in the
DAC-X-VOUT-CMP-CONFIG register.
shows the list of hard-coded discrete points for the sine wave
with 12-bit resolution and
shows the pictorial representation of the sine wave. There are four phase
settings available for the sine wave that are selected using the PHASE-SEL-X bit in the DAC-X-FUNC-CONFIG
register.
Table 7-10. Sine Wave Data Points
SEQUENCE
12-BIT VALUE
SEQUENCE
12-BIT VALUE
0
0x800
12
0x800
1
0x9A8
13
0x658
2
0xB33
14
0x4CD
3
0xC87
15
0x379
4
0xD8B
16
0x275
5
0xE2F
17
0x1D1
6
0xE66
18
0x19A
7
0xE2F
19
0x1D1
8
0xD8B
20
0x275
9
0xC87
21
0x379
10
0xB33
22
0x4CD
11
0x9A8
23
0x658
TIME PERIOD
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
0
Figure 7-12. Sine Wave Generation
SLASF47 – MAY 2022
40
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