The RT8070 is a simple, easy-to-use current mode controlled 4A synchronous step-down DC-DC converter with an input supply voltage range from 2.7V to 5.5V. The device built-in an accurate 0.8V reference voltage and integrates low RDS(ON) power MOSFETs to achieve high efficiency in both WDFN-8L 3x3 and SOP-8 (Exposed Pad) packages.

The RT8070 operates in automatic PSM that maintains high efficiency during light load operation. The device features cycle-by-cycle current-limit protection to prevent the device from the catastrophic damage in output short circuit, over-current or inductor saturation. Adjustable soft-start function prevents inrush current during start-up. The device also features input under-voltage lockout, output under-voltage protection, and over-temperature protection to provide safe and smooth operation in all operating conditions.


  • LCD TVs and Monitors
  • Notebook Computers
  • Distributed Power Systems
  • IP Phones
  • Digital Cameras
Key Spec.
Status Active
Vin (min) (V) 2.7
Vin (max) (V) 5.5
Number of Outputs 1
Vout (min) (V) 0.8
Vout (max) (V) 5
Output Adj. Method Resistor
Iout (max) (A) 4
Current Limit (typ) (A) 5.8
Freq (typ) (kHz) 1000
Freq (min) (kHz) 200
Freq (max) (kHz) 2000
Ext Sync No
Ron_HS (typ) (mOhm) 110
Ron_LS (typ) (mOhm) 70
Iq (typ) (mA) 0.46
Features 100% Duty Cycle;Adjustable Frequency;Adjustable Soft-Start;Current Mode Control;Cycle-by-Cycle Current Limit;Diode Emulation Mode;Enable Input;Fast Transient Response;OCP;PSM;Power Good;Stable with Ceramic Capacitor;UVP
Package Type PSOP-8;WDFN3x3-8
  • Input Voltage Range from 2.7V to 5.5V
  • Integrated 110mΩ and 70mΩ FETs
  • 100% Duty Cycle for Lowest Dropout
  • Power Saving Mode for Light Loads
  • Adjustable Frequency : 200kHz to 2MHz
  • 0.8V Reference Allows Low Output Voltage
  • Enable Function
  • External Soft-Start
  • Power Good Function
  • Input Under-Voltage Lockout Protection
  • Output Under-Voltage Protection
  • Over-Temperature Protection
  • RoHS Compliant and Halogen Free
TitleLast UpdateDownload
4A, 2MHz, Synchronous Step-Down Converter2018/12/19
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
RT8070ZQWWDFN3x3-81500 Request Buy from Distributor
RT8070ZSPPSOP-82500 Request Buy from Distributor