TLC320AD55 Datasheet, PDF (29/41 Pages) Texas Instruments – Sigma-Delta Analog Interface Circuit

4.4.3.3 ADC Signal-to-Distortion+Noise (see Note 5)
PARAMETER
TEST CONDITIONS
MIN TYP MAX UNIT
VI = – 9 dB
80
83
VI = – 1 dB
72
76
Total harmonic distortion+noise (THD+N)
VI = – 40 dB
40
45
dB
VI = – 65 dB
14
20
VI(AUXM, _AUXP) = – 9 dB
72
77
NOTE 5: The test condition is a 1020 Hz input signal with an 8 kHz conversion rate. Input and output voltages are
referred to VDD /2.
4.4.4 ADC Channel
PARAMETER
TEST CONDITIONS MIN TYP MAX UNIT
Dynamic range
86
dB
Interchannel isolation
80
dB
Gain error
Gain error, dc
VI = – 1 dB at 1020 Hz
INP = 3 V, INM = 2 V
± 0.5 dB
± 0.6
dB
Off-set error, ADC converter
8
mV
CMRR
Common-mode rejection ratio INM, INP or
AUXM, AUXP
VI = 0 dB at 1020 kHz
80
dB
Idle channel noise (on-chip reference)
50 µV rms
Ri
Input resistance
TA = 25°C
70 100
kΩ
4.4.5 DAC Path Filter (see Note 6)
PARAMETER
TEST CONDITIONS MIN TYP MAX UNIT
20 Hz
–0.5 0.08 0.15
200 Hz
– 0.5 0.08 0.15
300 Hz to 3 kHz – 0.15 0.08 0.15
Filter gain relative to gain at 1020 Hz
3.3 kHz
– 0.35 0.11 0.3 dB
3.4 kHz
–1 – .48 – 0.1
4 kHz
– 20 –14
≥ 4.6 kHz
– 40
NOTE 6: The filter gain outside of the passband is measured with respect to the gain at 1020 Hz. The input signal is the
digital equivalent of a sine wave (digital full scale = 0 dB). The nominal differential DAC channel peak-to-peak
output voltage with this input condition is 6 V. The pass band is 0 to 3600 Hz.
4–3