Table 7-31. Logarithmic-Slew Mode: FUNC-GEN-CONFIG-BLOCK Field Descriptions
Bit
Field
Type
Reset
Description
12-11
PHASE-SEL-X
R/W
0
00: 0°
01: 120°
10: 240°
11: 90°
10-8
FUNC-CONFIG-X
R/W
0
000: Triangular wave
001: Sawtooth wave
010: Inverse sawtooth wave
100: Sine wave
111: Disable function generation
Others: Invalid
7
LOG-SLEW-EN-X
R/W
0
1: Enable logarithmic slew.
In logarithmic slew mode, the DAC output moves from the DAC-
X-MARGIN-LOW code to the DAC-X-MARGIN-HIGH code, or
vice versa, in 3.125% steps.
When slewing in the positive direction, the next step is
(1 + 0.03125) times the current step.
When slewing in the negative direction, the next step is
(1 – 0.03125) times the current step.
When DAC-X-MARGIN-LOW is 0, the slew starts from code 1.
The time interval for each step is defined by RISE-SLEW-X and
FALL-SLEW-X.
6-4
RISE-SLEW-X
R/W
0
SLEW-RATE for logarithmic slew mode (DAC-X-MARGIN-LOW to
DAC-X-MARGIN-HIGH):
000: 4 µs/step
001: 12 µs/step
010: 27.04 µs/step
011: 60.72 µs/step
100: 136.72 µs/step
101: 418.64 µs/step
110: 1282 µs/step
111: 5127.92 µs/step
3-1
FALL-SLEW-X
R/W
0
SLEW-RATE for logarithmic slew mode (DAC-X-MARGIN-HIGH
to DAC-X-MARGIN-LOW):
000: 4 µs/step
001: 12 µs/step
010: 27.04 µs/step
011: 60.72 µs/step
100: 136.72 µs/step
101: 418.64 µs/step
110: 1282 µs/step
111: 5127.92 µs/step
0
X
X
0
Don't care
SLASF47 – MAY 2022
Copyright © 2022 Texas Instruments Incorporated
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