Rainbow Electronics MAX1402 User Manual
Page 22
MAX1402
+5V, 18-Bit, Low-Power, Multichannel,
Oversampling (Sigma-Delta) ADC
22
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0
DIFF
0
A1
0
0
1
0
0
1
0
1
2
0
2
1
0
0
1
1
0
X
1
1
0
X
0
X
2
1
2
1
0
1
0
1
0
2
SCAN
0
1
1
TRANSFER
FUNCTION REG.
1
X
1
X
3
1
0
0
0
X
0
X
3
1
0
X
1
X
1
1
3
3
1
1
0
A0
1
0
1
1
X
X
X
0
1
0
3
X
X
X
X
CALGAIN+ – CALGAIN-
CALGAIN+ – CALGAIN-
CALGAIN+ – CALGAIN-
CALGAIN+ – CALGAIN-
AIN2–AIN6
AIN4–AIN6
AIN3–AIN6
Do Not Use
CALGAIN+ – CALGAIN-
CHANNEL
1
CALGAIN+ – CALGAIN-
CALGAIN+ – CALGAIN-
CALOFF+ – CALOFF-
AIN1–AIN2
CALGAIN+ – CALGAIN-
AIN5–AIN6
1
X
1
X
3
1
3
2
1
1
X
X
X
X
AIN5–AIN6
CALGAIN+ – CALGAIN-
CALOFF+ – CALOFF-
AIN3–AIN4
0
X
1
1
X
AIN1–AIN6
1
1
1
1
Do Not Use
Table 10. Transfer-Function Register Mapping—Gain-Cal Mode (M1 = 1, M0 = 0)
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.
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.
X = Don’t care
AUXILIARY DATA
CHANNEL ID TAG
D1
DS0
D0
‘0’
DS1
CID0
DATA BITS
CID2
CID1
RESERVED
(Data LSB)
(LSB)
D9
D5
D8
D7
D6
D2
DATA BITS
D4
D3
D17
D13
D16
D15
D14
D10
DATA BITS
D12
D11
First Bit (Data MSB)
Data Register (Read-Only) Bits