C8051F330_07 Datasheet, PDF (44/216 Pages) Silicon Laboratories – Mixed Signal ISP Flash MCU Family

C8051F330/1/2/3/4/5
measured from ‘0’ to VREF x 1023/1024. Example codes are shown below for both right-justified and left-
justified data. Unused bits in the ADC0H and ADC0L registers are set to ‘0’.
Input Voltage
VREF x 1023/1024
VREF x 512/1024
VREF x 256/1024
0
Right-Justified ADC0H:ADC0L
(AD0LJST = 0)
0x03FF
0x0200
0x0100
0x0000
Left-Justified ADC0H:ADC0L
(AD0LJST = 1)
0xFFC0
0x8000
0x4000
0x0000
When in Differential Mode, conversion codes are represented as 10-bit signed 2’s complement numbers.
Inputs are measured from –VREF to VREF x 511/512. Example codes are shown below for both right-jus-
tified and left-justified data. For right-justified data, the unused MSBs of ADC0H are a sign-extension of the
data word. For left-justified data, the unused LSBs in the ADC0L register are set to ‘0’.
Input Voltage
VREF x 511/512
VREF x 256/512
0
–VREF x 256/512
–VREF
Right-Justified ADC0H:ADC0L
(AD0LJST = 0)
0x01FF
0x0100
0x0000
0xFF00
0xFE00
Left-Justified ADC0H:ADC0L
(AD0LJST = 1)
0x7FC0
0x4000
0x0000
0xC000
0x8000
Important Note About ADC0 Input Configuration: Port pins selected as ADC0 inputs should be config-
ured as analog inputs, and should be skipped by the Digital Crossbar. To configure a Port pin for analog
input, set to ‘0’ the corresponding bit in register PnMDIN (for n = 0,1). To force the Crossbar to skip a Port
pin, set to ‘1’ the corresponding bit in register PnSKIP (for n = 0,1). See Section “14. Port Input/Output”
on page 125 for more Port I/O configuration details.
5.2. Temperature Sensor
The typical temperature sensor transfer function is shown in Figure 5.2. The output voltage (V_TEMP) is the
positive ADC input when the temperature sensor is selected by bits AMX0P4–0 in register AMX0P.
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Rev. 1.5