AN4325 datasheet(9/27 Pages) STMICROELECTRONICS

9 / 27 page

DocID024966 Rev 1

9/27

AN4325

Power supplies and reset sources of the STM32F030 family

1.2

Reset and power supply supervisor

1.2.1

Power-on reset (POR) / power-down reset (PDR)

The device has an integrated power-on reset (POR) and power-down reset (PDR) circuits

which are always active and ensure proper operation above a threshold of 2.4 V.

The device remains in Reset mode when the monitored supply voltage is below a specified

threshold, VPOR/PDR, without the need for an external reset circuit.



The POR monitors only the VDD supply voltage. During the startup phase VDDA must

arrive first and be greater than or equal to VDD.



The PDR monitors both the VDD and VDDA supply voltages. However, the VDDA power

supply supervisor can be disabled (by programming a dedicated option bit

VDDA_MONITOR) to reduce the power consumption if the application design ensures that

VDDA is higher than or equal to VDD.

For more details on the power on / power down reset threshold, refer to the electrical

characteristics section in the datasheet.

Figure 3. Power on reset/power down reset waveform

AN4325 Datasheet(PDF) 9 Page - STMicroelectronics