Summary of features

AN2658

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Doc ID 14152 Rev 2

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Summary of features

Table 1. below summarizes the main features of the STM8 ADC.

2.1

Resolution

The STM8 ADC converter has 10-bit resolution. A special extra feature of the STM8 is that,

to read the conversion results faster, and if you can accept lower resolution; you can read

only 8 of the 10 bits, provided that you select the appropriate register alignment.

The register for configuring right or left data alignment is ADC_CR2.

2.2

Clock selection

The A/D conversion speed is given by the ADC clock signal. This clock speed must be

between 1 MHz and 4 or 6 MHz (refer to datasheet). The ADC clock frequency is selected

by dividing the frequency of the master clock.

The register for clock speed selection is ADC_CR1.

Table 1.

STM8 ADC features

Feature

STM8 ADC

Resolution

10-bit

Clock speed

Triggers

Software, timer or external pin trigger

Operating modes

Single or continuous mode

Conversion speed

Reference voltage

Number of input channels

Up to 16 channels

Data format

Optional left or right alignment

1.

Available only on ADC1 (extended ADC type)

Up to 16 data buffer registers (depending on the number of

channels)

Special functions (1)

Scan mode, analog watchdog, buffer overrun flag, bandgap

reference voltage channel