Datasheet

ADC Conversion
Pulse Repetition Period (PRP)
T = 1 / PRF
ADC Reset
ADC_RDY Pin
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
0%
25%
50%
75%
ADC Data
ADC Data 1 are
written into
register 42.
ADC Data 5 are
written into
register 43.
ADC Data 9 are
written into
register 44.
ADC Data 13 are written into
register 45.
Register 42  register 43
are written into register 46.
Register 44 register 45
are written into register 47.
0%
17 18 19 20
0 T
1.0 T
NUMAV[7:0] + 1 =
0.25 Pulse Repetition Period´
50 sm
- 1
AFE4490
www.ti.com SBAS602F –DECEMBER 2012–REVISED OCTOBER 2013
The number of samples to be used per conversion phase is specified in the CONTROL1 register (NUMAV[7:0]).
The user must specify the correct value for the number of averages, as described in Equation 3:
(3)
When the number of averages is '0', the averaging is disabled and only one ADC sample is written to the result
registers.
Note that he number of average conversions is limited by 25% of the PRF. For example, eight samples can be
averaged with PRF = 625 Hz, and four samples can be averaged with PRF = 1250 Hz.
Figure 65. ADC Data Without Averaging (When Number of Averages = 0)
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