32L476GDISCOVERY datasheet(10/37 Pages) STMICROELECTRONICS

10 / 37 page

Getting started with demonstration

UM1919

10/37

DocID028080 Rev 1

2.3

Power supply modes

The demonstration firmware provides two modes of operation depending on the power

supply mode. The richest power supply mode is the USB-powered where all the

applications can run at a maximum clock speed whereas an alternative mode consists in

running from the battery. The battery mode allows to demonstrate the low-power

consumption of MCU but also the HW itself. The demonstration firmware implements thus

some clock reduction mechanisms, enters automatically in low-power modes in case of

inactivity and wake-up in case of end-user interaction with the joystick.

2.3.1

USB supply

The following jumper setup is mandatory for running the demonstration powered by the USB

(ST-LINK):

•

Jumpers RST (JP3) / ST-LINK (CN3) present

•

Jumper JP5 on IDD

•

Jumper JP6 on 3V3

2.3.2

Battery supply

The following jumper setup is mandatory for running the demonstration powered by the

battery (see Figure 4):

•

Jumpers RST (JP3) / ST-LINK (CN3) removed

•

Jumper JP5 on IDD

•

Jumper JP6 on BATT

And of course it insures that a CR2032 battery is present at the rear of the board.

32L476GDISCOVERY Datasheet(PDF) 10 Page - STMicroelectronics