MAX1403_02 Datasheet, PDF (21/36 Pages) Maxim Integrated Products – +3V, 18-Bit, Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC

+3V, 18-Bit, Low-Power, Multichannel,
Oversampling (Sigma-Delta) ADC
Table 10. Transfer-Function Register Mapping—Gain-Calibration Mode (M1 = 1, M0 = 0)
SCAN
DIFF
A1
A0
0
0
0
0
0
0
0
1
0
0
1
0
0
0
1
1
0
1
0
0
0
1
0
1
0
1
1
0
0
1
1
1
1
0
X
X
1
0
X
X
1
0
X
X
1
0
X
X
1
0
X
X
1
0
X
X
1
0
X
X
1
1
X
X
1
1
X
X
1
1
X
X
1
1
X
X
1
1
X
X
1
1
1
1
X = Don’t care
Data Register (Read-Only)
The data register is a 24-bit, read-only register. Any
attempt to write data to this location will have no effect.
If a write operation is attempted, 8 bits of data must be
clocked into the part before it will return to its normal
idle mode, expecting a write to the communications
register.
Data is output MSB first, followed by one reserved 0 bit,
two auxiliary data bits, and a 3-bit channel ID tag indi-
cating the channel from which the data originated.
CHANNEL
TRANSFER-
FUNCTION REGISTER
CALGAIN+–CALGAIN-
1
CALGAIN+–CALGAIN-
1
CALGAIN+–CALGAIN-
2
CALGAIN+–CALGAIN-
2
CALGAIN+–CALGAIN-
1
CALGAIN+–CALGAIN-
2
CALGAIN+–CALGAIN-
3
Do Not Use
AIN1–AIN6
1
AIN2–AIN6
1
AIN3–AIN6
2
AIN4–AIN6
2
AIN5–AIN6
3
CALOFF+–CALOFF-
3
CALGAIN+–CALGAIN-
3
AIN1–AIN2
1
AIN3–AIN4
2
AIN5–AIN6
3
CALOFF+–CALOFF-
3
CALGAIN+–CALGAIN-
3
Do Not Use
D17–D0: The conversion result. D17 is the MSB. The
result is in offset binary format. 00 0000 0000 0000
0000 represents the minimum value, and 11 1111 1111
1111 1111 represents the maximum value. Inputs
exceeding the available input range are limited to the
corresponding minimum or maximum output values.
0: This reserved bit will always be 0.
Data Register (Read-Only) Bits
First Bit (Data MSB)
DATA BITS
D17
D16
D15
D14
D13
D12
D11
D10
DATA BITS
D9
D8
D7
D6
D5
D4
D3
D2
(Data LSB)
DATA BITS
D1
D0
RESERVED
‘0’
AUXILIARY DATA
DS1
DS0
CID2
CHANNEL ID TAG
CID1
(LSB)
CID0
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