STMicroelectronics FlexSPIN: SPI configurable stepper and DC multi motor driver evaluation board EVAL6460 EVAL6460 Fiche De Données

   

   

   

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 Doc ID 17713 Rev 1

L6460 includes four H bridge power outputs (each one made by two independent half 
bridges) that are configurable in several different configurations.

Each half bridge is protected against: over-current, over-temperature and short circuit to 
ground, to supply or across the load. When an over current event occurs, all outputs are 
turned off (after a filter time), and the over current bit is stored in the internal status register 
that can be read through SPI.

Positive and negative voltage spikes, which occur when switching inductive loads, are 
limited by integrated freewheeling diodes (see 

).

During the start up procedure the bridges are in high impedance and after that they can be 
enabled through SPI. When a fault condition happens, i.e. an over-temperature event, the 
bridges return in their start-up condition and they need to be re-enabled from the micro 
controller.

The bridges can use PWM signals internally generated or externally provided (supplied 
through the GPIO pins). Internally generated PWM signals will run at approximately 
31.25kHz with a duty cycle that, through serial interface, can be programmed and 
incremented in steps of 1/(512*F

osc

). To reduce the peak current requested from supply 

voltage when all bridges are switching, the four internally generated PWM signals are out-
of-phase.

Each half bridge will use the PWM signal selected by the respective 
MtrXSelPWMSideY[1:0] (X stands for 1, 2, 3 or 4; Y stands for A or B) bits in the SPI, but if 
two half bridges are configured as a full bridge, only the PWM signal chosen for side A will 
be used to drive the resulting H bridge.

More in detail the PWM selection truth table will be as describe in the following tables:

#ONTROL

,OW

$RIVER

,OW

$RIVER

(IGH

$RIVER

(IGH

$RIVER

#ONTROL

(/%

PS

4&/4&

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