Datasheet LTC1863, LTC1867 (Analog Devices) - 10

LTC1863/LTC1867
APPLICATIONS INFORMATION Analog Input Multiplexer Changing the MUX Assignment “On the Fly”
The analog input multiplexer is controlled by a 7-bit input
1st Conversion 2nd Conversion
data word. The input data word is defined as follows: + SD OS S1 S0 COM UNI SLP CH2 – CH2 – { CH3 + { CH3 SD = SINGLE/DIFFERENTIAL BIT + CH4 + CH4 – { CH5 + { CH5 OS = ODD/SIGN BIT CH7/COM CH7/COM (–) (UNUSED) S1 = ADDRESS SELECT BIT 1 18637 AI02 S0 = ADDRESS SELECT BIT 0 Tables 1 and 2 show the configurations when COM = 0, COM = CH7/COM CONFIGURATION BIT and COM = 1. UNI = UNIPOLAR/BIPOLAR BIT
Table 1. Channel Configuration (When COM = 0, CH7/COM Pin Is Used as CH7)
SLP = SLEEP MODE BIT
Channel Configuration SD OS S1 S0 COM “+” “–” Examples of Multiplexer Options
0 0 0 0 0 CH0 CH1 0 0 0 1 0 CH2 CH3
4 Differential 8 Single-Ended
0 0 1 0 0 CH4 CH5 + (–) CH0 + CH0 0 0 1 1 0 CH6 CH7 – { (+) CH1 + CH1 + CH2 0 1 0 0 0 CH1 CH0 + (–) CH2 + CH3 – { (+) 0 1 0 1 0 CH3 CH2 CH3 + CH4 + CH5 + 0 1 1 0 0 CH5 CH4 (–){ CH4 + CH6 – (+) CH5 + 0 1 1 1 0 CH7 CH6 CH7/COM + (–) CH6 1 0 0 0 0 CH0 GND – (+){ CH7/COM GND (–) 1 0 0 1 0 CH2 GND 1 0 1 0 0 CH4 GND
7 Single-Ended Combinations of Differential
1 0 1 1 0 CH6 GND
to CH7/COM and Single-Ended
1 1 0 0 0 CH1 GND + CH0 + CH0 + { 1 1 0 1 0 CH3 GND CH1 – CH1 + CH2 1 1 1 0 0 CH5 GND + CH3 –{ CH2 + 1 1 1 1 0 CH7 GND CH4 + CH3 + CH5 + CH4 + CH6 + CH5
Table 2. Channel Configuration (When COM = 1, CH7/COM Pin
+ CH6 +
Is Used as COMMON)
CH7/COM CH7/COM (–) GND (–)
Channel Configuration
18637 AI01
SD OS S1 S0 COM “+” “–”
1 0 0 0 1 CH0 CH7/COM 1 0 0 1 1 CH2 CH7/COM 1 0 1 0 1 CH4 CH7/COM 1 0 1 1 1 CH6 CH7/COM 1 1 0 0 1 CH1 CH7/COM 1 1 0 1 1 CH3 CH7/COM 1 1 1 0 1 CH5 CH7/COM Rev. E 10 For more information www.analog.com Document Outline Features Applications Block Diagram Description Absolute Maximum Ratings Order Information Pin Configuration Converter Characteristics Dynamic Accuracy Analog Input Internal Reference Characteristics Digital Inputs and Digital Outputs Power Requirements Timing Characteristics Typical Performance Characteristics Pin Functions Typical Connection Diagram Test Circuits Timing Diagrams Applications Information Package Description Revision History Related Parts