MAX1036KEKA-T Maxim Integrated, MAX1036KEKA-T Datasheet - Page 19

• Manufacturer Part Number: MAX1036KEKA-T
• Description: Analog to Digital Converters - ADC
• Manufacturer: Maxim Integrated

Specifications of MAX1036KEKA-T

• Number Of Channels: 4/2
• Architecture: SAR
• Conversion Rate: 188 KSPs
• Resolution: 8 bit
• Input Type: Single-Ended/Pseudo-Differential
• Snr: 49 dB
• Interface Type: Serial (2-Wire, I2C)
• Operating Supply Voltage: 4.5 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Package / Case: SOT-23
• Maximum Power Dissipation: 567 mW
• Minimum Operating Temperature: - 40 C
• Number Of Converters: 1
• Voltage Reference: 4.096 V

The external reference can range from 1.0V to V
maximum conversion accuracy, the reference must be
able to deliver up to 30µA and have an output imped-
ance of 1kΩ or less. If the reference has a higher output
impedance or is noisy, bypass it to GND as close to
AIN_/REF as possible with a 0.1µF capacitor.
Output data coding for the MAX1036–MAX1039 is binary
in unipolar mode and two’s complement binary in bipolar
mode with 1LSB = (V
bits (8). Code transitions occur halfway between succes-
sive-integer LSB values. Figures 12 and 13 show the
input/output (I/O) transfer functions for unipolar and bi-
polar operations, respectively.
For best performance, use PC boards. Wire-wrap config-
urations are not recommended since the layout should
ensure proper separation of analog and digital traces. Do
not run analog and digital lines parallel to each other, and
do not lay out digital signal paths underneath the ADC
package. Use separate analog and digital PC board
ground sections with only one star point (Figure 14) con-
Table 5. Scanning Configuration
* When operating in external clock mode, there is no difference between SCAN[1:0] = 01 and SCAN[1:0] = 11 and converting continues
until a not acknowledge occurs.
Table 6. Reference Voltage and AIN_/REF Format
X = Don’t care.
SEL2
SCAN1
0
0
1
1
1
0
0
1
1
SEL1
Layout, Grounding, and Bypassing
0
1
0
0
1
2.7V to 3.6V and 4.5V to 5.5V, Low-Power,
SCAN0
______________________________________________________________________________________
0
1
0
1
SEL0
REF
X
X
X
0
1
4-/12-Channel 2-Wire Serial 8-Bit ADCs
/2
N
Scans up from AIN0 to the input selected by CS3–CS0 (default setting).
Converts the input selected by CS3–CS0 eight times.*
Scans up from AIN2 to the input selected by CS1 and CS0. When CS1 and CS0 are set for
AIN0–AIN2, the scanning stops at AIN2 (MAX1036/MAX1037).
Scans up from AIN6 to the input selected by CS3–CS0. When CS3–CS0 is set for AIN0–AIN6
scanning stops at AIN6 (MAX1038/MAX1039).
Converts the channel selected by CS3–CS0.*
) where N is the number of
V
External reference
Internal reference
Internal reference
Internal reference
DD
Transfer Functions
REFERENCE VOLTAGE
External Reference
DD
. For
SCANNING CONFIGURATION
Analog input
Reference input
Analog input
Analog input
Reference output
necting the two ground systems (analog and digital). For
lowest noise operation, ensure the ground return to the
star ground’s power supply is low impedance and as
short as possible. Route digital signals far away from sen-
sitive analog and reference inputs.
High-frequency noise in the power supply (V
influence the proper operation of the ADC’s fast
comparator. Bypass V
0.1µF capacitor located as close as possible to the
MAX1036–MAX1039 power-supply pin. Minimize
capacitor lead length for best supply-noise rejection,
and add an attenuation resistor (5Ω) if the power sup-
ply is extremely noisy.
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 endpoints of the transfer function,
once offset and gain errors have been nullified. The INL
is measured using the endpoint method.
AIN_/REF
DD
Always Off
Always Off
Auto Shutdown
Always On
Always On
to the star ground with a
Integral Nonlinearity
INTERNAL REFERENCE
STATE
Definitions
DD
) could
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