RT6338
8A, 23V Synchronous Step-Down Converter with 3.3V/5V LDO
General Description
Features
⚫ Input Voltage Range
The RT6338 family are high efficiency synchronous
step-down DC-DC converters with pseudo constant
switching frequency 500kHz and deliver up to 8A output
current. The RT6338A/B and RT6338AH/BH operate
from 4.5V to 23V input voltage. The output voltage of
RT6338A/AH is programmed between 0.6V to 5.5V and
RT6338B/BH is fixed to 3.3V output voltage. The input
voltage of RT6338C/CH ranges from 5.2V to 23V and
the output voltage of RT6338C/CH is fixed to 5.1V.
RT6338A/B and RT6338AH/BH : 4.5V to 23V
RT6338C/CH : 5.2V to 23V
⚫ Output Voltage
RT6338A/AH : 0.6V to 5.5V
RT6338B/BH : 3.3V
RT6338C/CH : 5.1V
⚫ 8A Continuous Output Current
⚫ Stable with POSCAP and MLCC Capacitor
⚫ Fast Transient Response
The RT6338 adopts Advanced Constant On-Time
⚫ Diode Emulation Mode (DEM) for Power Saving
⚫ Ultrasonic Mode (USM) for Avoiding Acoustic
Noise
®
(ACOT ) control architecture that provides ultra-fast
transient response and further reduces the external
®
component count. In steady states, the ACOT
⚫ Pseudo Constant Switching Frequency 500kHz in
CCM
operates at nearly constant switching frequency over
line, load and output voltage ranges and makes the EMI
filter design easier.
⚫ Internal Power MOSFET Switch 26m (high-side)
and 14m (low-side)
By setting the voltage of the EN/MODE pin, RT6338
operates either in diode emulation mode (DEM) or
ultrasonic mode (USM) at light load. The USM
maintains operation frequency above 25kHz, which
eliminates the acoustic noise. In the DEM, RT6338
provides the best light-load efficiency and improves the
acoustic noise with spread spectrum function.
⚫ LDO
RT6338B/BH : 3.3V/100mA
RT6338C/CH : 5V/100mA
⚫ Over-Current Limit
RT6338A/AH : Adjustable (10A, 12A or 14A)
RT6338B/BH/C/CH : 12A
⚫ Output Under-/Over-Voltage Protection (UVP/OVP)
RT6338A/B/C : Latched Mode UVP/OVP
RT6338AH/BH/CH : Hiccup Mode UVP and Non-
Latched Mode OVP
RT6338 provides PGOOD indicator for easy system
sequence control. Full protection features are also
integrated in the device, including the cycle-by-cycle
current limit, OVP, UVP, input UVLO and OTP.
⚫ Input Under-Voltage Lockout (UVLO)
⚫ Over-Temperature Protection (OTP)
RT6338A/B/C : Latched Mode OTP
RT6338AH/BH/CH : Non-Latched Mode OTP
All above functions are integrated in a UQFN-23L 3x3
(FC) package.
Applications
⚫ Laptop Computers
⚫ Tablet PCs
⚫ Networking Systems
⚫ Servers
⚫ Personal Video Recorders
⚫ Flat Panel Television and Monitors
⚫ Distributed Power Systems
Copyright © 2023 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS6338-04
August 2023
www.richtek.com
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