SY21248BRAC - High Efficiency Fast Response 8A, 23V Input Synchronous Step Down Regulator


  • Low RDS(ON) for Internal Switches (Top/Bottom): 22/11 mΩ
  • Wide Input Voltage Range: 4-23V
  • 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.
  • 8A Output Current Capability
  • ±1.5% Output Voltage Accuracy
  • Power Good Indicator
  • Output Discharge Function
  • Output Current Limit Protection
  • Output Under Voltage, Over Voltage Latch Off Protection
  • Input UVLO
  • Over Temperature Protection
  • RoHS Compliant and Halogen Free
  • Compact Package: QFN3x3-20

Typical Application


The SY21248B develops a high efficiency synchronous step-down DC/DC regulator capable of delivering 8A current. The device integrates main switch and synchronous switch with very low RDS(ON) to minimize the conduction loss. The SY21248B also integrates a 100mA LDO with bypass switch.

The SY21248B 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