MAX1403 Maxim, MAX1403 Datasheet - Page 21

• Manufacturer Part Number: MAX1403
• Description: +3V / 18-Bit / Low-Power / Multichannel / Oversampling Sigma-Delta ADC
• Manufacturer: Maxim

X = Don’t care
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.
Data Register (Read-Only) Bits
First Bit (Data MSB)
Table 10. Transfer-Function Register Mapping—Gain-Calibration Mode (M1 = 1, M0 = 0)
SCAN
D17
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
D9
D1
DATA BITS
(Data LSB)
DIFF
______________________________________________________________________________________
0
0
0
0
1
1
1
1
0
0
0
0
0
0
0
1
1
1
1
1
1
D16
D8
D0
+3V, 18-Bit, Low-Power, Multichannel,
Data Register (Read-Only)
A1
RESERVED
X
X
X
X
X
X
X
X
X
X
X
X
0
0
1
1
0
0
1
1
1
D15
D7
‘0’
Oversampling (Sigma-Delta) ADC
A0
X
X
X
X
X
X
X
X
X
X
X
X
0
1
0
1
0
1
0
1
1
DS1
D14
D6
AUXILIARY DATA
DATA BITS
DATA BITS
CALGAIN+–CALGAIN-
CALGAIN+–CALGAIN-
CALGAIN+–CALGAIN-
CALGAIN+–CALGAIN-
CALGAIN+–CALGAIN-
CALGAIN+–CALGAIN-
CALGAIN+–CALGAIN-
CALGAIN+–CALGAIN-
CALGAIN+–CALGAIN-
CALOFF+–CALOFF-
CALOFF+–CALOFF-
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.
CHANNEL
AIN1–AIN6
AIN2–AIN6
AIN3–AIN6
AIN4–AIN6
AIN5–AIN6
AIN1–AIN2
AIN3–AIN4
AIN5–AIN6
DS0
D13
D5
CID2
D12
Do Not Use
Do Not Use
D4
CHANNEL ID TAG
FUNCTION REGISTER
CID1
D11
D3
TRANSFER-
1
1
2
2
1
2
3
1
1
2
2
3
3
3
1
2
3
3
3
CID0
D10
D2
(LSB)
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