SY21236BRAC - High Efficiency Fast Response, 6A, 23V Input Synchronous Step Down Regulator


  • Low RDS(ON) for Internal Switches (Top/Bottom): 38/19 mΩ
  • Wide Input Voltage Range: 4-23V
  • 3.3V LDO with Individual Enable Control and Bypass Switch
  • Integrated Bypass Switch: 1.5Ω
  • Instant PWM Architecture to Achieve Fast Transient Responses
  • Internal 1.2ms Soft-start Limits the Inrush Current
  • Pseudo-constant Frequency: 600kHz.
  • 6A Output Current Capability
  • +/-1.5% Output Voltage Accuracy
  • Power Good Indicator
  • Output Discharge Function
  • Output Current Limit Protection
  • Short Circuit Latch-off Protection
  • Output Over Voltage Latch-off Protection
  • Input UVLO
  • Over Temperature Protection
  • RoHS Compliant and Halogen Free
  • Compact Package: QFN3×3-20

Typical Application


The SY21236B develops a high efficiency synchronous step-down DC/DC regulator with 3.3V fixed output voltage and 6A current rating. The device integrates main switch and synchronous switch with very low RDS(ON) to minimize the conduction loss. The SY21236B also integrates a 3.3V/100mA LDO with bypass switch and individual enable control.

The SY21236B operates over a wide input voltage range from 4V to 23V. The DC/DC regulator adopts the instant PWM architecture to achieve fast transient responses for high step down applications and high efficiency at light loads. In addition, it operates at pseudo-constant frequency of 600kHz under heavy load conditions to minimize the size of inductor and capacitor.


  • LCD-TV/Net-TV/3DTV
  • Set Top Box
  • Notebook
  • High Power AP