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

RT5758 Feature Product

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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 (ACOT®) control architecture that provides ultrafast transient response and further reduce the external-component count. In steady states, the ACOT® 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.


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Key Spec.
Status Active
Vin (min) (V) 3
Vin (max) (V) 6
Number of Outputs 1
Vout (min) (V) 0.6
Vout (max) (V) 3.3
Output Adj. Method Resistor
Iout (max) (A) 9
Current Limit (typ) (A) 10.8
Freq (typ) (kHz) 1000
Ext Sync No
Ron_HS (typ) (mOhm) 12
Ron_LS (typ) (mOhm) 8
Iq (typ) (mA) 0.1
Features ACOT Control;Adjustable Soft-Start;Built-in Bootstrap Switch;Cycle-by-Cycle Current Limit;Enable Input;Fast Transient Response;Internal Compensation;PSM;Power Good;Stable with Ceramic Capacitor;UVP
Package Type UQFN3x3-13(FC)
  • 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
TitleLast UpdateShareDownload
9A, 6.5V, 1MHz Synchronous Step-Down Converter2018/05/22
Technical Documents
TitleLast UpdateShareDownload
Richtek Selection Guide [Oct., 2020]2020/12/30
Reference Design
TitleLast UpdateShareDownload
Richtek Load Transient Tool2021/01/21
Part NumberPackage TypePackage Qty.Free SampleBuy From Authorized Distributor
RT5758GQUFUQFN3x3-13(FC)1500 Request Buy from Distributor
RT5758GQUFUQFN3x3-13(FC)3000 Request Buy from Distributor