S3F80JB

COMPARATOR

 

 

COMPARATOR OPERATION

The comparator compares input analog voltage at CIN0–CIN3 with an external or internal reference voltage

(VREF) 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 VREF + 150 mV

If "0" Analog input voltage VREF – 150 mV

To obtain a comparison result, the data must be read out from the CMPREG register after VREF is updated by changing the CMOD value after a conversion time has elapsed.

Analog Input Voltage (CIN0-3)

Reference Voltage (VREF)

Comparision Time

(CMPCLK x8)

Comparator Clock (fosc/16, fosc/128)

Comparision

Comparision

 

 

 

 

 

 

 

 

 

Start

 

End

 

 

 

 

 

 

 

 

 

Comparision Result

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(CMPREG)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Unknown

 

1

 

1

 

Unknown

 

0

 

 

 

 

 

 

 

 

 

 

 

 

Figure 14-2. Conversion Characteristics

14-3

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Image 277
Samsung S3F80JB manual Comparator Operation, Conversion Characteristics