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

The switching regulator controller output driving stage can be represented with an 
equivalent circuit as in the 

:

As can be seen from the above figure, the external switch gate is charged with a current 
generator I

SOURCE

 and it is discharged towards ground with a current generator I

SINK

 that is 

applied for a T

SINK

 pulse while an equivalent resistor R

SUSTAIN

 is connected between gate 

and source until the sink command is present.

This controller can implement a step-down switching regulator used to provide a regulated 
voltage in the range 0.8 V – 32 V. Such kind of variation could be managed by considering 
some constraints in the application and particularly by choosing the correct feedback 
reference voltage as indicated in the 

         

V

SWDRV_gate 

VPUMP 

I

SOURCE

 

V

SWDRV_SW 

R

SUSTAIN

 

Source command

 

Sink pulse command

 

I

SINK

 

Sink command

 

Tsink 

0.8V 

≤ V

out

 < 5V

0.8V - 1V

5V 

≤ V

out

 

≤ 32V

2.5V - 3V