Check whether Reset Pin has internal Pull-up.
Always prefer to Pull it up using exernal resistors
Place a nominal value of 1 to 10 uF capacitor between ground and the Reset Pin. a 20 pF capacitor for ESD protection. Here it is assumed that Reset Pin of MCU is active low. It means, to reset the MCU, user has to give a low pulse (0 V) on Pin RESET for a specified duration. THe reset duration of MCU will be specified in the data sheet (Minimum). Always providing a reset until all power supplies have reached 90% of their nominal value is a good practice.
A resistor between power supply and RESET pin of MCU is required to delay in the reset pulse for the MCU further and also provides pull-up. The delay will be 4 times RC. A schotty diode with its positive terminal to Reset Pin and negative terminal to the Power supply will be helpful to kill out the positive going spikes which may occur during switch operation.
If space and price options are flexible, there are dedicated IC from Maxim, TI and other vendors which serves both voltage good detection and reset generation along with switch debouncing circuit, all in one IC.
Pictures to be uploaded.
waveform to be uploaded
Always prefer to Pull it up using exernal resistors
Place a nominal value of 1 to 10 uF capacitor between ground and the Reset Pin. a 20 pF capacitor for ESD protection. Here it is assumed that Reset Pin of MCU is active low. It means, to reset the MCU, user has to give a low pulse (0 V) on Pin RESET for a specified duration. THe reset duration of MCU will be specified in the data sheet (Minimum). Always providing a reset until all power supplies have reached 90% of their nominal value is a good practice.
A resistor between power supply and RESET pin of MCU is required to delay in the reset pulse for the MCU further and also provides pull-up. The delay will be 4 times RC. A schotty diode with its positive terminal to Reset Pin and negative terminal to the Power supply will be helpful to kill out the positive going spikes which may occur during switch operation.
If space and price options are flexible, there are dedicated IC from Maxim, TI and other vendors which serves both voltage good detection and reset generation along with switch debouncing circuit, all in one IC.
Pictures to be uploaded.
waveform to be uploaded
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