Power_LDO ICs

E522.51 | Dual Buck-Quad LDO


SMPS: Voltage mode buck converter system.
Both buck converters can be activated via high voltage capable pins ON1 and/or ON2.

LDO1: High voltage input LDO
LDO2-4: Low voltage input LDOs

Power Monitoring:
PGOOD indicates undisturbed operation of all regulators.

RSTN provides a reset for the controller in case of watchdog error or system undervoltage.

FS_ON sends a failsafe signal if the watchdog is not triggered properly.

Internal state registers can be read via SPI 


  • Fixed frequency primary buck converter
    VIN max. 40V | VOUT from 4V to 6V | IOUT max. 800mA
  • Fixed frequency secondary buck converter
    VIN max. 6V | VOUT from 0.8V to 5.1V | IOUT max. 800mA
  • LDO 1 (Master) Input voltage max. to 40V supporting always-on
    mode, Outp. voltage progr. in 0.05V steps, IOUT max. 320mA
  • LDO 2 - 4 (with tracking option) Input voltage max. 6V
    Output voltage programmable in 0.05V steps, IOUT max. 350mA


  • Microcontroller supply

Ordering Information

  • Samples
    Part No.TempJunc RangePackageOrder No.
    E522.51-40°C to +105°CQFN48L7E52251A78B


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Application Diagram

Dual Buck-Quad LDO