TL7231MD Datasheet, PDF (28/37 Pages) Samsung semiconductor – FULL LAYER-III ISO/IEC 11172-3 AUDIO DECODER

TL7231MD
ADC
The internal ADC of TL7231MD is 12-bit resolution ADC. It is recycling type ADC with sample-
and-hold function. The analog input ADCAIN should be single-ended type with the range from
ADCREFP to ADCREFN. This ADCAIN voltage follows reference voltage range fundamentally.
So, if user wants to alter the input range, the voltage value of ADCREFP should be changed.
But ADCREFP should be greater than 2.0V. The characteristic of internal ADC is shown Table 8.
Table 8. Characteristics of Internal ADC
PARAMETER
THD
SNR
SNDR
MIN
TYP
MAX
74.3
64.9
64.4
(ADCVDDD/ADCVDDA=3.0V, ADCAIN=8KHz)
UNITS
dB
dB
dB
3.0V
10u
0.1u
ADCREFP
ADCREFP/2
ADCREFN
Vref
10u
ADCVDDA ADCVSSA ADCVBB
ADCAIN
ADCREFP
0.1u
ADCREFN
TL7231MD
ADCVDDD ADCVSSD
3.0V
0.1u
10u
Figure 19. Reference Circuit when using internal ADC
With TL7231MD, the following circuit in Figure 19 is recommended to use internal ADC.
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SAMSUNG Electronics Co.