Datasheet

35Maxim Integrated
MAX11335–MAX11340
500ksps, 12-/10-Bit, 4-/8-/16-Channel ADCs with
Post-Mux External Signal Conditioning Access
Definitions
Integral Nonlinearity
Integral nonlinearity (INL) is the deviation of the values
on an actual transfer function from a straight line. This
straight line can be either a best-straight-line fit or a line
drawn between the end points of the transfer function,
once offset and gain errors have been nulled. The static
linearity parameters for the MAX11335–MAX11340 are
measured using the end-points method.
Differential Nonlinearity
Differential nonlinearity (DNL) is the difference between
an actual step width and the ideal value of 1 LSB. A DNL
error specification of 1 LSB or less guarantees no miss-
ing codes and a monotonic transfer function.
Signal-to-Noise Ratio
Signal-to-noise ratio is the ratio of the amplitude of the
desired signal to the amplitude of noise signals at a
given point in time. The larger the number, the better. The
theoretical minimum analog-to-digital noise is caused by
quantization error and results directly from the ADC’s
resolution (N bits):
SNR = (6.02 x N + 1.76) dB
In reality, there are other noise sources besides quantiza-
tion 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 fundamental, the first five
harmonics, and the DC offset.
Total Harmonic Distortion
Total harmonic distortion (THD) is expressed as:
2222
2345
1
VVVV
THD 20 log
V

+++

= ×



where V
1
is the fundamental amplitude, and V
2
through V
5
are the amplitudes of the 2nd- through 5th-order harmonics.
Spurious-Free Dynamic Range
Spurious-free dynamic range (SFDR) is the ratio of the
RMS amplitude of the fundamental (maximum signal
component) to the RMS value of the next largest distor-
tion component.
Full-Power Bandwidth
Full-power bandwidth is the frequency at which the input
signal amplitude attenuates by 3dB for a full-scale input.
Table 15. Recommended Input Amplifiers
Table 16. Recommended References
REFERENCE CHANNELS TYPICAL APPLICATION
MAX4430 1 Dual supply, low noise, low distortion, high bandwidth
MAX4432 2 Dual supply, low noise, low distortion, high bandwidth
MAX4454 4 Low power, single, supply, low cost
MAX4418 4 Low noise, low power, high bandwidth
MAX44263 2 Low power, precision, CMOS input, rail-to-rail I/O
REFERENCE TYPICAL APPLICATION
MAX6126 Ultra-high precision, ultra-low noise, wide temperature range
MAX6033 Ultra-high precision, low noise, low power, wide temperature range
MAX6043 High precision, wide temperature range
MAX6129B Low cost, ultra-low power
MAX6003 Low cost, low power