9A, 6.5V, 1MHz Synchronous Step-Down Converter

Topology: Buck
Input Voltage (min.): 3.00 V
Input Voltage (max.): 6.50 V
Switching Frequency (min.): 800.00 kHz
Switching Frequency (max.): 1200.00 kHz
Output 1: 3.30 V / 9.000 A

Original publication on 2018-04-26, revision 1


The RT5758 is a high-performance, synchronous step-down DC-DC converter that can deliver up to 9A output current from a 3V to 6.5V input supply. The device integrates low RDS(ON) power MOSFETs, accurate 0.6V reference and an integrated diode of bootstrap circuit to offer a very compact solution. The RT5758 adopts Advanced Constant On-Time (ACOTTM) control architecture that provides ultrafast transient response and further reduce the external-component count. In steady states, the ACOTTM operates in nearly constant switching frequency over line, load and output voltage ranges and makes the EMI filter design easier. The device offers Independent enable control input pin and power good indicator for easily sequence control. To control the inrush current during the startup, the device provides a programmable soft-start up by an external capacitor connected to the SS pin. Fully protection features are also integrated in the device including the cycle-by-cycle current limit control, UVP, input UVLO and OTP. The RT5758 is available in a thermally enhanced UQFN-13L 3x3 (FC) package.


  • Dramatically Fast Transient Response
  • Steady 1MHz ±20% Switching Frequency
  • 1.5% Reference Voltage
  • Advanced COT Control Loop
  • Auto PWM/Pulse Skipping Mode for High Light-Load Efficiency
  • Optimized for Ceramic Output Capacitors
  • 3V to 6.5V Input Voltage Range
  • Integrated 12mΩ/8mΩ MOSFETs
  • Pre-Biased Start Up
  • Adjustable Soft-Start
  • Power Good Indicator
  • Enable Control
  • Over-Current and Over-Temperature Protections
  • Under-Voltage Protection with Hiccup Mode


  Order Code SPEC Product series L
Material Version Samples
744314047 PDF WE-HCI SMT Flat Wire High Current Inductor 0.47 18 0.38 20 1.35 235 Superflux SMT