Creo que no los llevan por esto:
SR Input used to set synchronous rectification mode. When a
PWM off-cycle is triggered, load current recirculates according
to the decay mode selected by the control logic. The synchronous
rectification feature turns on the appropriate MOSFETs during
the current decay and effectively shorts out the body diodes with
the low RDS(ON) of the MOSFET. This lowers power dissipation
significantly and eliminates the need for additional Schottky
diodes. Synchronous rectification can be set to either active mode
or disabled mode.
• Active Mode When the SR pin input is logic low, active mode
is enabled and synchronous rectification will occur. This mode
prevents reversal of the load current by turning off synchronous
rectification when a zero current level is detected. This
prevents the motor winding from conducting in the reverse
direction.
• Disabled Mode When the SR pin input is logic high, synchronous
rectification is disabled. This mode is typically used when
external diodes are required to transfer power dissipation from
the power MOSFETs to external, usually Schottky, diodes.
Aún así me han puesto el pin SR con una pull-up. ¿?
Saludos.