Datasheet

LTC1096/LTC1096L
LTC1098/LTC1098L
18
10968fc
APPLICATIONS INFORMATION
Multiplexer (MUX) Address
The bits of the input word following the START bit assign
the MUX confi guration for the requested conversion. For
a given channel selection, the converter will measure the
voltage between the two channels indicated by the “+”
and “–” signs in the selected row of the followintg tables.
In single-ended mode, all input channels are measured
with respect to GND.
MSB-First/LSB-First (MSBF)
The output data of the LTC1098(L) is programmed for
MSB-fi rst or LSB-fi rst sequence using the MSBF bit.
When the MSBF bit is a logical one, data will appear on
the D
OUT
line in MSB-fi rst format. Logical zeros will be
fi lled in indefi nitely following the last data bit. When the
MSBF bit is a logical zero, LSB-fi rst data will follow the
normal MSB-fi rst data on the D
OUT
line. (see Operating
Sequence)
MUX ADDRESS
SGL/DIFF
1
1
0
0
ODD/SIGN
0
1
0
1
CHANNEL #
0
+
+
–
1
+
–
+
GND
–
–
SINGLE-ENDED MUX MODE
DIFFERENTIAL MUX MODE
10968 AI03
OUTPUT CODE
1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 0
•
•
•
0 0 0 0 0 0 0 1
0 0 0 0 0 0 0 0
INPUT VOLTAGE
V
REF
– 1LSB
V
REF
– 2LSB
•
•
•
1LSB
0V
INPUT VOLTAGE
(V
REF
= 5.000V)
4.9805V
4.9609V
•
•
•
0.0195V
0V
10968 AI05
0V 1LSB
V
REF
–2LSB
V
REF
–1LSB
V
REF
V
IN
0 0 0 0 0 0 0 1
0 0 0 0 0 0 0 0
1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 0
•
•
•
10968 AI04
Unipolar Transfer Curve
The LTC1096(L)/LTC1098(L) are permanently confi gured
for unipolar only. The input span and code assignment for
this conversion type are shown in the following fi gures
for a 5V reference.
Unipolar Transfer Curve
LTC1098(L) Channel Selection
Unipolar Output Code
Operation with D
IN
and D
OUT
Tied Together
The LTC1098(L) can be operated with D
IN
and D
OUT
tied
together. This eliminates one of the lines required to com-
municate to the microprocessor (MPU). Data is transmit-
ted in both directions on a single wire. The processor pin
connected to this data line should be confi gurable as either
an input or an output. The LTC1098(L) will take control of