STMicroelectronics FlexSPIN: SPI configurable stepper and DC multi motor driver evaluation board EVAL6460 EVAL6460 Data Sheet

   

   

   

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 Doc ID 17713 Rev 1

As soon as V

Supply

 and V

SupplyInt

 are above their power on reset level, L6460 will start the 

charge pump circuit; once V

Pump

 voltage reaches its under voltage rising threshold, L6460 

begins a sequence that starts the regulators considered system regulators.

A regulator is considered a System regulator if:

–

It has to start in on state without any user action.

–

It is included in the power-up sequence.

–

Its under-voltage event is considered by L6460 as an error condition to be 
signaled through nRESET pin.

Once V

Supply

 and V

SupplyInt

, V

Pump

 and all the system regulators are over their under 

voltage rising threshold, L6460 enters in the normal operating state, that will release 
nRESET pin and will wait for SPI commands.

L6460 will reduce the noise introduced in the system by switching out of phase all its power 
circuits (switching regulators, bridges and charge pump).

The L6460's startup sequence of operation is the following:

–

start V

3v3

 internal linear regulator

–

sample startup configuration

–

wait enable if slave device

–

start charge pump

–

start system regulators (see order in 

)

–

if master send enable to slave device 

–

wait until V

GPIO_SPI

 becomes ok