MAX1036 Datasheet, PDF (20/22 Pages) Maxim Integrated Products – 2.7V to 5.5V, Low-Power, 4-/12-Channel 2-Wire Serial 8-Bit ADCs

2.7V to 5.5V, Low-Power, 4-/12-Channel
2-Wire Serial 8-Bit ADCs
OUTPUT CODE
REF
1...111
1...110
1...101
1...100
1LSB = ^VREF
256
0...011
0...010
0...001
0...000
0123
INPUT VOLTAGE (LSB)
252 253 254 255 256
Figure 12. Unipolar Transfer Function
OUTPUT CODE
(TWO'S COMPLEMENT)
REF
0...111
0...110
0...101
0...100
1LSB = ^VREF
256
0...001
0...000
1...111
1...011
1...010
1...001
1...000
-128 -127 -126 -125
-1 0 +1
'-' INPUT
INPUT VOLTAGE (LSB)
Figure 13. Bipolar Transfer Function
+124 +125 +126 +127 +128
3V/5V
SUPPLIES
V_LOGIC = 3V/5V GND
R* = 5Ω
0.1µF
V_DD
GND
3V/5V DGND
*OPTIONAL
MAX1036
MAX1037
MAX1038
MAX1039
DIGITAL
CIRCUITRY
Figure 14. Power-Supply and Grounding Connections
Differential Nonlinearity
Differential nonlinearity (DNL) is the difference between
an actual step width and the ideal value of 1LSB. A
DNL error specification of less than 1LSB guarantees
no missing codes and a monotonic transfer function.
Aperture Jitter
Aperture jitter (t_AJ) is the sample-to-sample variation in
the time between the samples.
Aperture Delay
Aperture delay (t_AD) is the time between the rising
edge of the sampling clock and the instant when an
actual sample is taken.
Signal-to-Noise Ratio
For a waveform perfectly reconstructed from digital sam-
ples, signal-to-noise ratio (SNR) is the ratio of full-scale
analog input (RMS value) to the RMS quantization error
(residual error). The ideal, theoretical minimum analog-
to-digital noise is caused by quantization error only and
results directly from the ADC’s resolution (N bits):
SNR = (6.02 ✕ N + 1.76)dB
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