LTC1293_15 Datasheet, PDF (11/28 Pages) Linear Technology – Single Chip 12-Bit Data Acquisition System

LTC1293/LTC1294/LTC1296
APPLICATI S I FOR ATIO
Table 1a. LTC1294/6 Multiplexer Channel Selection
MUX ADDRESS
SGL/ ODD SELECT
DIFF SIGN 1 0
0 0 00
0 0 01
0 0 10
0 0 11
0 1 00
0 1 01
0 1 10
0 1 11
DIFFERENTIAL CHANNEL SELECTION
01 234 5 6 7
+–
+–
+–
+–
–+
–+
–+
–+
MUX ADDRESS
SGL/ ODD SELECT
DIFF SIGN 1 0
1 0 00
1 0 01
1 0 10
1 0 11
1 1 00
1 1 01
1 1 10
1 1 11
SINGLE-ENDED CHANNEL SELECTION
0 1 2 3 4 5 6 7 COM
+
–
+
–
+
–
+
–
+
–
+
–
+
–
+–
Table 1b. LTC1293 Channel Selection
MUX ADDRESS
SGL/ ODD SELECT
DIFF SIGN 1 0
0 0 00
0 0 01
0 0 10
0 0 11
0 1 00
0 1 01
0 1 10
0 1 11
DIFFERENTIAL CHANNEL SELECTION
0 12 34 5
+–
+–
+–
Not Used
–+
–+
–+
Not Used
MUX ADDRESS
SGL/ ODD SELECT
DIFF SIGN 1 0
1 0 00
1 0 01
1 0 10
1 0 11
1 1 00
11
11
01
10
1 1 11
SINGLE-ENDED CHANNEL SELECTION
0 1 2 3 4 5 COM
+
–
+
–
+
–
Not Used
+
–
+
–
+–
Not Used
Unipolar/Bipolar (UNI)
The UNI bit determines whether the conversion will be
unipolar or bipolar. When UNI is a logical one, a unipolar
conversion will be performed on the selected input volt-
age. When UNI is a logical zero, a bipolar conversion will
result. The input span and code assignment for each
conversion type are shown in the figures below:
Unipolar Transfer Curve (UNI = 1)
Unipolar Output Code (UNI = 1)
OUTPUT CODE
INPUT VOLTAGE
INPUT VOLTAGE (VREF = 5V)
111111111111
111111111110
•
•
•
000000000001
000000000000
V_REF – 1LSB
V_REF – 2LSB
•
•
•
1LSB
0V
4.9988V
4.9976V
•
•
•
0.0012V
0V
LTC1293 AI03a
111111111111
111111111110
•
•
•
000000000001
000000000000
V_IN
LTC1293 AI03b
129346fs
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