24V, 2A, 500kHz, ACOTTM Step-Down Converter in 8 Pin TSOT-23


Update Alert Share

The RT6215A/B is a simple, easy-to-use, 2A synchronous step-down DC-DC converter with an input supply voltage range of 4.5V to 24V. The device build-in an accurate 0.791V reference voltage and integrates low RDS(ON) power MOSFETs to achieve high efficiency in a SOT23-8 package.

The RT6215A/B adopts Advanced Constant On-Time (ACOT®) control architecture to provide an ultrafast transient response with few external components and to operate in nearly constant switching frequency over the line, load, and output voltage range. The RT6215A operates in automatic PSM that maintains high efficiency during light load operation. The RT6215B operates in Forced PWM that helps meet tight voltage regulation accuracy requirements.

The RT6215A/B senses both FETs current for a robust over-current protection. It features cycle-by-cycle current limit protection and prevent the device from the catastrophic damage in output short circuit, over current or inductor saturation. An externally adjustable soft-start function prevents inrush current during start-up. The device also includes input under-voltage lockout, output under-voltage protection, and over-temperature protection (thermal shutdown) to provide safe and smooth operation in all operating conditions. The RT6215A/B is offered in a TSOT-23-8(FC) package.


  • Set Top Box
  • Portable TV
  • Access Point Router
  • DSL Modem
  • LCD TV
Key Spec.
RT6215A RT6215B
Status Active Active
Vin (min) (V) 4.5 4.5
Vin (max) (V) 24 24
Number of Outputs 1 1
Vout (min) (V) 0.791 0.791
Vout (max) (V) 5 5
Output Adj. Method Resistor Resistor
Iout (max) (A) 2 2
Current Limit (typ) (A) 2.7 2.7
Freq (typ) (kHz) 500 500
Ext Sync No No
Ron_HS (typ) (mOhm) 100 100
Ron_LS (typ) (mOhm) 85 85
Iq (typ) (mA) 0.17 0.17
Features ACOT Control;Adjustable Soft-Start;Cycle-by-Cycle Current Limit;Enable Input;Fast Transient Response;PSM;Power Good ACOT Control;Adjustable Soft-Start;Cycle-by-Cycle Current Limit;Enable Input;Fast Transient Response;Force PWM;Power Good
Package Type TSOT-28(FC) TSOT-28(FC)
  • 2A Converter With Built-In 100mΩ/85mΩ Low RDS(ON) Power FETs
  • Input Supply Voltage Range : 4.5V to 24V
  • Output Voltage Range : 0.791V to 5V
  • Advanced Constant On-Time (ACOTTM) Control
  • Ultrafast Transient Response
  • No Needs For External Compensations
  • Optimized for Low-ESR Ceramic Output Capacitors
  • 0.791V ±1.5% High-Accuracy Feedback Reference Voltage
  • Low Quiescent Current (170μA typ.)
  • Both HS/LS FETs Protection for Robust Over-Current Protection
  • Optional for Operation Modes :
    ► Power Saving Mode (PSM) at Light Load (RT6215A)
    ► Forced PWM Mode (RT6215B)
  • Light-load VOUT Ripple Reduction Technology in PSM
  • Fixed Switching Frequency : 500kHz
  • Externally Adjustable Soft-Start
  • Monotonic Start-Up for Pre-Biased Output
  • Input Under-Voltage Lockout (UVLO)
  • Output Under-Voltage Protection (UVP) with Hiccup Mode
  • Power Good Indication
  • Enable Control
  • Available In TSOT-23-8 (FC) Package
TitleLast UpdateShareDownload
24V, 2A, 500kHz, ACOTTM Step-Down Converter in 8 Pin TSOT-232017/02/08
Technical Documents
TitleLast UpdateShareDownload
Richtek Selection Guide [Oct., 2020]2020/12/30
Reference Design
TitleLast UpdateShareDownload
Richtek Load Transient Tool2021/01/21