Texas Instruments TLV2553EVM, Руководство пользователя

Страница: 13 / 25

www.ti.com
TLV2553EVM-PDK Operation
13 SBAU247A – June 2015 – Revised September 2019
Submit Documentation Feedback
Copyright © 2015–2019, Texas Instruments Incorporated
TLV2553EVM-PDK Evaluation Module
Effective resolution can then be computed by definition, as shown in Equation 2 :
Effective Resolution (bits) = 12 – LOG
2
(N
RMS_ADCOUT
) = 12 – LOG
2
(
σ
DC) → (2) (2)
Note that in the case of the TLV2553EVM, the onboard ADC drive circuits and power supply are all
optimized for a low noise contribution. Therefore, assuming the EVM analog inputs are driven by low-
noise dc voltage sources, the ADC RMS output noise is dominated by the intrinsic thermal noise of the
TLV2553 itself, which is generally less than 1-LSB RMS. As a result,
Equation 2 produces a value of
effective resolution that is greater than 12 bits (which is of course not possible but desirable nonetheless).
If however, the input signal source has significant noise contribution, then
σ DC may exceed 1 LSB in
which case the effective resolution drops to a value less than 12 bits, indicating a loss of resolution.
Again, the histogram tool offers multichannel functionality. However, the histogram corresponding to a
single input channel is displayed at any time, as shown in
Figure 12 .
Figure 12. Histogram Tool Input Channel Selection