ST7263BEX datasheet(13/186 Pages) STMICROELECTRONICS

13 / 186 page

ST7263Bxx

Pin description

Doc ID 7516 Rev 8

13/186

Pin description

2.1

RESET signal (bidirectional)

It is active low and forces the initialization of the MCU. This event is the top priority non

maskable interrupt. This pin is switched low when the Watchdog is triggered or the VDD is

low. It can be used to reset external peripherals.

Note:

Adding two 100 nF decoupling capacitors on the Reset pin (respectively connected to VDD

and VSS) will significantly improve product electromagnetic susceptibility performance.

2.2

OSCIN/OSCOUT: input/output oscillator pin

These pins connect a parallel-resonant crystal, or an external source, to the on-chip

oscillator.

2.3

VDD/VSS

Main power supply and ground voltages

Note:

To enhance the reliability of operation, it is recommended that VDDA and VDD be connected

together on the application board. This also applies to VSSA and VSS.

2.4

VDDA/VSSA

Power supply and ground voltages for analog peripherals.

Note:

To enhance the reliability of operation, it is recommended that VDDA and VDD be connected

together on the application board. This also applies to VSSA and VSS.

2.5

Alternate functions

Several pins of the I/O ports assume software programmable alternate functions as shown

in the pin description.

Note:

The USBOE alternate function is mapped on Port C2 in 32/34/48 pin devices. In SO24

devices it is mapped on Port B1.

The timer OCMP1 alternate function is mapped on Port A6 in 32/34/48 pin devices. In SO24

devices it is not available.

ST7263BEx Datasheet(PDF) 13 Page - STMicroelectronics