The RT8259 is a high voltage buck converter that can support the input voltage range from 4.5V to 24V and the output current can be up to 1.2A. Current Mode operation provides fast transient response and eases loop stabilization.
The chip also provides protection functions such as cycle-by-cycle current limiting and thermal shutdown protection. The RT8259 is available in a SOT-23-6 and TSOT-23-6 packages.


  • Distributed Power Systems
  • Battery Charger
  • Pre-Regulator for Linear Regulators
  • WLED Drivers
Key Spec.
Status Active
Vin (min) (V) 4.5
Vin (max) (V) 24
Number of Outputs 1
Vout (min) (V) 0.8
Vout (max) (V) 15
Output Adj. Method Resistor
Iout (max) (A) 1.2
Current Limit (typ) (A) 2.1
Freq (typ) (kHz) 1400
Ext Sync No
Ron_HS (typ) (mOhm) 300
Ron_LS (typ) (mOhm) 300
Iq (typ) (mA) 0.55
Features Current Mode Control;Cycle-by-Cycle Current Limit;Enable Input;Force PWM;Internal Compensation;OCP;OTP;Stable with Ceramic Capacitor;UVP
Package Type SOT-26;TSOT-26
  • Wide Operating Input Voltage Range : 4.5V to 24V
  • Adjustable Output Voltage Range : 0.8V to 15V
  • 1.2A Output Current
  • 0.3Ω Internal Power MOSFET Switch
  • High Efficiency up to 92%
  • 1.4MHz Fixed Switching Frequency
  • Stable with Low ESR Output Ceramic Capacitors
  • Thermal Shutdown
  • Cycle-By-Cycle Over Current Protection
  • RoHS Compliant and Halogen Free
TitleLast UpdateShareDownload
1.2A, 24V, 1.4MHz Step-Down Converter2008/11/14
Title Last Update ShareDownload
1.2A, 24V, 1.4MHz Step-Down Converter 2015/05/19
Technical Documents
TitleLast UpdateShareDownload
Richtek Selection Guide [Oct., 2022]2022/10/01
Multi-Source Power Management Design2022/04/26
TitleLast UpdateShareViews
How to estimate control loop bandwidth from the transient response time?2017/03/30 1611
Reference Design
TitleLast UpdateShareDownload
Richtek Load Transient Tool2022/07/25
Part NumberPackage TypePackage Qty.Free SampleBuy From Authorized Distributor
RT8259GESOT-263000 Request Not available
RT8259GESOT-263000 Request Buy from Distributor
RT8259GJ6TSOT-263000 Request Not available
RT8259GJ6TSOT-263000 Request Buy from Distributor