Samsung S3F80JB - Manual (Page 277)

S3F80JB COMPARATOR
14-3
COMPARATOR OPERATION
The comparator compares input analog voltage at CIN0–CIN3 with an external or internal reference voltage
(V
REF
) that is selected by the CMOD register. The result is written to the comparison result register CMPREG at
address EAH, Set1, Bank1. The comparison result at internal reference is calculated as follows:
If "1" Analog input voltage
≥ V
REF
+ 150 mV
If "0" Analog input voltage
≤ V
REF
– 150 mV
To obtain a comparison result, the data must be read out from the CMPREG register after V
REF
is updated by
changing the CMOD value after a conversion time has elapsed.
Comparision Time
(CMPCLK x8)
Comparision
Start
Comparision
End
Unknown 1 1 Unknown 0
Analog Input Voltage (CIN0-3)
Reference Voltage (V REF )
Comparator Clock
(fosc/16, fosc/128)
Comparision Result
(CMPREG)
Figure 14-2. Conversion Characteristics