ES51992
11,000 Counts ADC
3. Multi Channel Input
ES51992 provides VIN+, VIN1+, VIN2+ and Vin- pins to achieve the multi channel
input (multiplexer) feature. Because ES51992 is a single core A-to-D converter, it can
only process one pack of data per conversion period. Although it has four input pins, it
would take only one pair as input channel from the four pins. The actual input channel
is determined by the bits CH1/CH0 of STATUS Byte1 as the following table:
Input Channel CH1 CH0
ch1
0
0
ch2
0
1
ch3
1
0
ch4
1
1
High Input
VIN+
VIN1+
VIN2+
VIN2+
Low Input
VIN-
VIN-
VIN-
VIN1+
ES51992 also configures an input channel rotation (polling) feature. The rotation
feature can be activated by setting the ROT bit of STATUS Byte2 to high. In the
rotation mode, the actual input channel will be changed by ES51992 sequentially and
automatically. The rotation feature has two types, one is for three input channel rotation
with the same low input, another one is for two independent differential channel
rotation. The following table presents the configuration of the rotation type.
Rotation Type Table:
ROT
CH1,CH0
0,0
0,1
H
1,0
1,1
L
-
Rotation Type
ch1
→
ch2
→
ch3
→
ch1
…
ch1
→
ch4
→
ch1
…
Not Rotating
7
06/09/20
CYRUSTEK [ Cyrustek corporation ]
