AN2168

3 Reset management

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3

Reset management

3.1

External reset circuitry

Figure 5 and Figure 6 summarize the hardware required to operate a good reset. The first one

should be used when the power down mode is not required by the application, whereas the

second one shows the hardware configuration in order to use the power down mode.

Figure 5.

External reset circuitry when power down mode is not used

Figure 6.

External reset circuitry when power down mode is used

3.2

How to reset external devices with ST10F27x reset signals

If the application uses the ST10F27x with external devices, such as other microcontrollers, and

if the external devices should be reset by the ST10F27x beyond the ST10 reset, there are two

ways to do this:

●

Using the RSTOUT pin

●

Using the bidirectional reset option provided by the ST10F27x

VDD

ST10F27x

GND

RPD

VDD

220K-1M

R0

RSTIN

External Reset

Circuitry

Reset Signal

Open Drain Output

VDD

ST10F27x

GND

RPD

VDD

220K-1M

R0

RSTIN

External Reset

Circuitry

Reset Signal

Open Drain Output

GND

1uF