MAX1034_12 Datasheet, PDF (18/31 Pages) Maxim Integrated Products – 8-/4-Channel, ±VREF Multirange Inputs,Serial 14-Bit ADCs

8-/4-Channel, ±V_REF Multirange Inputs,
Serial 14-Bit ADCs
Table 3. Input Data Word Formats
OPERATION
DATA BIT
D7
D6
D5
D4
D3
D2
(START)
Conversion-Start Byte
(Tables 4 and 5)
1
C2
C1
C0
0
0
Analog-Input Configuration Byte
(Table 2)
1
C2
C1
C0
DIF/SGL
R2
Mode-Control Byte
(Table 7)
1
M2
M1
M0
1
0
Table 4. Channel Selection in Single-Ended Mode (DIF/SGL = 0)
CHANNEL-SELECT BIT
CHANNEL
C2
C1
C0
CH0
CH1
CH2
CH3
CH4
CH5
CH6
0
0
0
+
0
0
1
+
0
1
0
+
0
1
1
+
1
0
0
+
1
0
1
+
1
1
0
+
1
1
1
Table 5. Channel Selection in True-Differential Mode (DIF/SGL = 1)
CHANNEL-SELECT BIT
C2
C1
C0
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
CH0
+
CH1
-
CH2
+
CHANNEL
CH3
CH4
CH5
RESERVED
-
RESERVED
+
-
RESERVED
RESERVED
CH6
+
D1
D0
0
0
R1
R0
0
0
CH7
+
AGND1
-
-
-
-
-
-
-
-
CH7 AGND1
-
Differential Common-Mode Range
The MAX1034/MAX1035 differential common-mode
range (V_CMDR) must remain within -4.75V to +5.5V to
obtain valid conversion results. The differential com-
mon-mode range is defined as:
(^CH_+) ⁺ (^CH_−)
V_CMDR =
2
In addition to the common-mode input voltage limita-
tions, each individual analog input must be limited to
±6V with respect to AGND1.
The range-select bits R[2:0] in the analog input configu-
ration bytes determine the full-scale range for the corre-
sponding channel (Tables 2 and 6). Figures 9, 10, and
11 show the valid analog input voltage ranges for
the MAX1034/MAX1035 when operating with FSR =
V_REF / 2, FSR = V_REF, and FSR = 2 x V_REF, respectively.
The shaded area contains the valid common-mode
voltage ranges that support the entire FSR.
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