Datasheet

Data Sheet ADuC845/ADuC847/ADuC848
Rev. C | Page 47 of 108
ICON (EXCITATION CURRENT SOURCES CONTROL REGISTER)
The ICON register is used to configure the current sources and the burnout detection source.
SFR Address: D5H
Power-On Default: 00H
Bit Addressable: No
Table 30. Excitation Current Source SFR Bit Designations
Bit No. Name Description
7 ––– Not Implemented. Write Don’t Care.
6 ICON.6 Burnout Current Enable Bit.
When set, this bit enables the sensor burnout current sources on primary ADC channels AIN5/AIN6 or
AIN7/AIN8. Not available on any other ADC input pins or on the auxiliary ADC (ADuC845 only).
5 ICON.5 Not Implemented. Write Don’t Care.
4 ICON.4 Not Implemented. Write Don’t Care.
3 ICON.3 IEXC2 Pin Select. 0 selects AIN8, 1 selects AIN7
2 ICON.2 IEXC1 Pin Select. 0 selects AIN7, 1 selects AIN8
1 ICON.1 IEXC2 Enable Bit (0 = disable).
0 ICON.0 IEXC1 Enable Bit (0 = disable).
A write to the ICON register has an immediate effect but does not reset the ADCs. Therefore, if a current source is changed while an ADC
is already converting, the user must wait until the third or fourth output at least (depending on the status of the chop mode) to see a fully
settled new output.
Both IEXC1 and IEXC2 can be configured to operate on the same output pin thereby increasing the current source capability to 400 µA.