AN2645 datasheet(20/36 Pages) STMICROELECTRONICS

20 / 36 page

Block-by-block compatibility analysis

AN2645

20/36

3.1.4

Digital power supply and package pinout

The digital power supply design includes two supply sources. The purpose is to distribute

the current flowing through the I/O logic separately from the rest of the digital microcontroller

circuits. Up to two VDDIO / VSSIO pin pairs are used as well as the main VDD / VSS digital

supply pair, depending on the pin-count:

●

Both VDDIO pairs are present in all larger packages, from the 80-pin package down to

the 44 pin package.

●

The 32-pin package has only one VDDIO pin for supplying power to the I/Os in the

STM8S207x and STM8S105x sub-families.

●

The STM8S103x and STM8S903x sub-families have no particular pins dedicated to

supplying I/Os. All their I/Os are supplied by the main VDD/VSS pin pair.

The total output current is limited by the number of supply pins. The total output current

capability declines for smaller packages, regardless of the number of I/Os with high-sink

capability.

The VCAP pin for connecting the external decoupling capacitor for the internal 1.8V regulator

is present on all packages.

3.1.5

ADC power supply and voltage reference in package pinout

The analog power supply design includes an extra power supply for the analog parts of the

microcontroller and an external reference voltage connected via an extra pin pair.

●

The VDDA/VSSA analog supply pin pair is present on all larger packages, from the 80-

pin package down to the 32-pin package, except in the STM8S103x and STM8S903x

sub-families.

●

The STM8S103x and STM8S903x sub-families take the analog supply from the main

digital supply VDD/VSS pin pair.

●

The external ADC voltage reference pair VREF+/VREF- is present in the 80 and 64 pin

packages used by the Performance line family only. Without these pins, it is not

possible to use the ADC zooming function feature (see Section 3.4: Analog-to-digital

converter for more details).

●

For the rest of the family the ADC reference is taken from the main analog supply VDDA.

Table 16.

Overview of power supply pins used in all packages

STM8S

LQFP80

(xxxM)

LQFP64

(xxxR)

LQFP48

(xxxC)

LQFP44

(xxxS)

LQFP32

(xxxK)

LQFP20

(xxxF)

VDD / VSS / VCAP

••

•

VDDIO1 / VSSIO1

VDDIO2 / VSSIO2

••

•(1)

The 32-pin package has an incomplete I/O supply pair consisting of a single VDDIO pin. This pin is not

available for STM8S103x & STM8S903x sub-family devices.

AN2645 датащи(PDF) 20 Page - STMicroelectronics

AN2645 датащи(HTML) 20 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

датащи скачать

ссылки URL