MAX1136 Datasheet, PDF (20/22 Pages) Maxim Integrated Products – 2.7V to 3.6V and 4.5V to 5.5V, Low-Power, 4-/12-Channel, 2-Wire Serial 10-Bit ADCs

2.7V to 3.6V and 4.5V to 5.5V, Low-Power,
4-/12-Channel, 2-Wire Serial 10-Bit ADCs
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
ADC’s full-scale range, calculate the ENOB as follows:
SINAD(dB)
=
20
×

log_

SignalRMS
NoiseRMS + THDRMS



ENOB = (SINAD - 1.76)/6.02
Total Harmonic Distortion
Total harmonic distortion (THD) is the ratio of the RMS
sum of the input signal’s first five harmonics to the fun-
damental itself. This is expressed as:

THD
=
20
×
log





V₂₂
+
V₃₂ + V₄₂
V₁
+
V₅₂






where V₁ is the fundamental amplitude, and V₂ through V₅
are the amplitudes of the 2nd through 5th order harmonics.
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
MAX1136/MAX1137 TRANSISTORS COUNT: 11,362
MAX1138/MAX1139 TRANSISTORS COUNT: 12,956
PROCESS: BiCMOS
Typical Operating Circuit
0.1mF
3.3V or 5V
V_DD
ANALOG
INPUTS
AIN0
AIN1
AIN3**/REF
MAX1136
MAX1137
MAX1138
MAX1139
C_REF
0.1mF
GND
*R_S
SDA
SCL
*R_S
5V
R_P
5V
R_P
mC
SDA
SCL
*OPTIONAL
**AIN11/REF (MAX1138/MAX1139)
TOP VIEW
Pin Configurations
AIN0 1
AIN1 2
AIN2 3
AIN3/REF 4
MAX1136
MAX1137
8 V_DD
7 GND
6 SDA
5 SCL
µMAX
Selector Guide
PART
MAX1136EUA
MAX1137EUA
MAX1138EEE
MAX1139EEE
INPUT
CHANNELS
4
4
12
12
INTERNAL
REFERENCE
(V)
SUPPLY
VOLTAGE (V)
4.096
4.5 to 5.5
2.048
2.7 to 3.6
4.096
4.5 to 5.5
2.048
2.7 to 3.6
AIN0 1
AIN1 2
AIN2 3
AIN3 4
AIN4 5
AIN5 6
AIN6 7
AIN7 8
MAX1138
MAX1139
QSOP
16 AIN8
15 AIN9
14 AIN10
13 AIN11/REF
12 V_DD
11 GND
10 SDA
9 SCL
20 ______________________________________________________________________________________