4A, 21V 500kHz Synchronous Step-Down Converter


Update Alert Share

The RT8288A is a synchronous step-down regulator with an internal power MOSFET. It achieves 4A of continuous output current over a wide input supply range with excellent load and line regulation. Current mode operation provides fast transient response and eases loop stabilization.

Fault condition protection includes cycle-by-cycle current limiting and thermal shutdown. An internal soft-start minimizes external parts count and internal compensation circuitry.

The RT8288A requires a minimal number of readily available external components, providing a compact solution.


  • Distributive Power Systems
  • Battery Charger
  • DSL Modems
  • Pre-Regulator for Linear Regulators
Key Spec.
Status Active
Vin (min) (V) 4.5
Vin (max) (V) 21
Number of Outputs 1
Vout (min) (V) 0.808
Vout (max) (V) 15
Output Adj. Method Resistor
Iout (max) (A) 4
Current Limit (typ) (A) 7
Freq (typ) (kHz) 500
Ext Sync No
Ron_HS (typ) (mOhm) 120
Ron_LS (typ) (mOhm) 40
Iq (typ) (mA) 0.7
Features Current Mode Control;Enable Input;Force PWM;Internal Compensation;OCP;Stable with Ceramic Capacitor;UVP
Package Type PSOP-8
  • 4A Output Current
  • Internal Soft-Start
  • 120mΩ/40mΩ Internal Power MOSFET Switch
  • Internal Compensation Minimizes External Parts Count
  • Fixed 500kHz Frequency
  • Thermal Shutdown Protection
  • Cycle-by-Cycle Over Current Protection
  • Wide 4.5V to 21V Operating Input Range
  • Adjustable Output from 0.808V to 15V
  • Available in an SOP-8 (Exposed Pad) Package
  • RoHS Compliant and Halogen Free
TitleLast UpdateShareDownload
4A, 21V 500kHz Synchronous Step-Down Converter2011/07/22
Title Last Update ShareDownload
4A, 21V 500kHz Synchronous Step-Down Converter 2015/05/19
TitleLast UpdateShareViews
How to estimate control loop bandwidth from the transient response time?2017/03/30 1426
Reference Design
TitleLast UpdateShareDownload
Richtek Load Transient Tool2021/01/21