Omega Engineering OME-A8111 - Manual (Page 17)

2.4.7 A/D Multiplex Control Register
(WRITE) Base+A : A/D Multiplexer Control Register Format
Bit 7
Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
X X X X X D2 D1 D0
A/D input channel selection data =3 bits: D2...D0, D2=MSB, D0=LSB, X=don‘t care
Channel Bit_2 Bit_1 Bit_0
0 0 0 0
1 0 0 1
2 0 1 0
3 0 1 1
4 1 0 0
5 1 0 1
6 1 1 0
7 1 1 1
NOTE: The settling time of the multiplexer depends on the source resistance of input
sources.
Approx. Source resistance = 0.1 KΩ Î Approx. Settling time = 3 µs.
Approx. Source resistance = 1 KΩ Î Approx. Settling time = 5 µs.
Approx. Source resistance = 10 KΩ Î Approx. Settling time = 10 µs.
Approx. Source resistance = 100 KΩ Î Approx. Settling time = 100 µs.
Sec 2.4.6 gives information about settling time delay.
OME-A-8111 Hardware Manual (ver.1.1, Jul/2003) 15