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DIFFERENT WAYS TO RESET ST7 MICROCONTROLLER

4 RECOMMENDATIONS TO PROVIDE A SAFE RESET

There are a few points which should always be kept in mind to avoid unwanted situations.

They are:

– To avoid the device from entering in ICC mode during a reset, it is mandatory to put an ex-

ternal pull-up of 10K on ICC CLK pin in a noisy environment (only in the case of devices that

do not have ICCSEL).

– The supply voltage should rise monotonously when the device is exiting from reset using In-

ternal LVD, to ensure application starts properly.

– The pull-down resistor at RESET pin should not be more than 10K for External Reset circuits.

– If the supply voltage is rising in steps please ensure that the first step is at 2V in less than

40msec so that the MCU starts properly.

– It is better to use External Reset circuits when the capacitive power supply is used, since the

supply voltage rises very slowly and is out of range of Internal LVD due to the large capaci-

tance value.

– Please refer the datasheet of the device carefully for certain device specific precautions/ rec-

ommendations.