MAX1084 Datasheet, PDF (14/16 Pages) Maxim Integrated Products – 400ksps/300ksps, Single-Supply, Low-Power, Serial 10-Bit ADCs with Internal Reference

400ksps/300ksps, Single-Supply, Low-Power,
Serial 10-Bit ADCs with Internal Reference
SUPPLIES
V_DD
V_DD GND
R* = 10Ω
4.7µF
0.1µF
VDD
GND
*OPTIONAL
MAX1084
MAX1085
V_DD DGND
DIGITAL
CIRCUITRY
Figure 14. Power-Supply Grounding Condition
SNR = (6.02 ✕ N + 1.76)dB
In reality, there are other noise sources besides quanti-
zation noise, including thermal noise, reference noise,
clock jitter, etc. Therefore, SNR is computed by taking
the ratio of the RMS signal to the RMS noise, which
includes all spectral components minus the fundamen-
tal, the first five harmonics, and the DC offset.
Signal-to-Noise Plus Distortion
Signal-to-noise plus distortion (SINAD) is the ratio of the
fundamental input frequency’s RMS amplitude to RMS
equivalent of all other ADC output signals.
SINAD (dB) = 20 ✕ log (SignalRMS / NoiseRMS)
Effective Number of Bits
Effective number of bits (ENOB) indicates the global
accuracy of an ADC at a specific input frequency and
sampling rate. An ideal ADC’s error consists of quanti-
zation noise only. With an input range equal to the full-
scale range of the ADC, calculate the effective number
of bits as follows:
ENOB = (SINAD - 1.76) / 6.02
Total Harmonic Distortion
Total harmonic distortion (THD) is the ratio of the RMS
sum of the first five harmonics of the input signal to the
fundamental itself. This is expressed as:
THD = 20 × LOG ^{V22 + V32 + V42 + V52}
V₁
where V1 is the fundamental amplitude, and V2 through
V5 are the amplitudes of the 2nd- through 5th-order
harmonics, respectively.
Spurious-Free Dynamic Range
Spurious-free dynamic range (SFDR) is the ratio of RMS
amplitude of the fundamental (maximum signal compo-
nent) to the RMS value of the next-largest distortion
component.
___________________Chip Information
TRANSISTOR COUNT: 4286
PROCESS: BiCMOS
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