The RT6224A/B is a high-efficiency, monolithic synchronous step-down DC-DC converter that can deliver up to 3.5A output peak current from a 4.3V to 18V input supply. The RT6224A/B adopts ACOT® architecture to allow the transient response to be improved and keep in constant frequency. Cycle-by-cycle current limit provides protection against shorted outputs and soft-start eliminates input current surge during start-up. Fault conditions also include output under-voltage protection, output over-voltage protection, and thermal shutdown.


  • Set Top Box
  • Portable TV
  • Access Point Router
  • DSL Modem
  • LCD TV
Key Spec.
RT6224A RT6224B
Status Active Active
Vin (min) (V) 4.3 4.3
Vin (max) (V) 18 18
Number of Outputs 1 1
Vout (min) (V) 0.6 0.6
Vout (max) (V) 5 5
Output Adj. Method Resistor Resistor
Iout (max) (A) 3 3
Current Limit (typ) (A) 4.4 4.4
Freq (typ) (kHz) 500 500
Ext Sync No No
Ron_HS (typ) (mOhm) 90 90
Ron_LS (typ) (mOhm) 45 45
Iq (typ) (mA) 0.5 0.5
Features ACOT Control;COT Control;Cycle-by-Cycle Current Limit;Enable Input;Internal Compensation;OCP;OTP;PSM;UVP ACOT Control;COT Control;Cycle-by-Cycle Current Limit;Enable Input;Internal Compensation;OCP;OTP;UVP
Package Type TSOT-26(FC) TSOT-26(FC)
  • Small Output Voltage at Light Load
  • High-Side Over-Current Limit
  • Integrated 90mΩ/45mΩ MOSFETs
  • 4.3V to 18V Supply Voltage Range
  • 500kHz Switching Frequency
  • ACOTTM Control
  • 0.6V ±1.5% Voltage Reference
  • Monotonic Start-Up into Pre-Biased Outputs
TitleLast UpdateDownload
3A, 18V, 500kHz ACOT® Synchronous Step-Down Converter2016/12/07
Technical Documents
TitleItem TypeLast UpdateDownload
Richtek Product Selection Guide [Jan., 2024] Selection Guide2024/01/18
Richtek Featured Product Tree [Aug., 2023] Selection Guide2023/08/07
Reference Design
TitleLast UpdateDownload
Richtek Load Transient Tool2022/07/25
Part NumberPackage TypePackage Qty.Free SampleBuy From Authorized Distributor
RT6224AHGJ6FTSOT-26(FC)3000 Request Buy from Distributor