®
RT6576E
Dual-Channel Synchronous DC/DC Step-Down Controller
with 5V/3.3V LDOs
General Description
The RT6576E is a dual-channel step-down controller
generating supply voltages for battery-powered systems.
It includes two Pulse-Width Modulation (PWM) controllers
adjustable from 2V to 5.5V, and two fixed 5V/3.3V linear
regulators. Each linear regulator provides up to 100mA
output current and 3.3V linear regulator provides 1%
accuracy under 35mA. The RT6576E has an oscillator
output to drive the external charge pump application. Other
features include on-board power-up sequencing, a power-
good output, internal soft-start, and soft-discharge output
that prevents negative voltage during shutdown.
A constant current ripple PWM control scheme operates
without sense resistors and provides 100ns response to
load transient. For maximizing power efficiency, the
RT6576E automatically switches to the diode-emulation
mode in light load applications. To eliminate noise in audio
applications, an audio-skipping mode is included, which
maintains the switching frequency above 25kHz. The
RT6576E is available in the WQFN-20L 3x3 package.
Features
Support Connected Standby Mode for Ultrabook
CCRCOT Control with 100ns Load Step Response
PWM Maximum Duty Ratio > 98%
5V to 25V Input Voltage Range
Dual Adjustable Output :
�½
CH1 : 2V to 5.5V
�½
CH2 : 2V to 4V
5V/3.3V LDOs with 100mA Output Current
1% Accuracy on 3.3V LDO Output
Oscillator Driving Output for Charge Pump
Application
Support Audio-Skipping Mode (ASM)
Internal Frequency Setting
�½
300kHz/355kHz (CH1/CH2)
Internal Soft-Start and Soft-Discharge
°
4700ppm/°C R
DS(ON)
Current Sensing
Independent Switcher Enable Control
Built-in OVP/UVP/OCP/OTP
Non-Latch UVLO
Power Good Indicator
Simplified Application Circuit
V
IN
UGATE2
RT6576E
BOOT2
UGATE1
PHASE2
BOOT1
LGATE2
PHASE1
VIN
LGATE1
FB2
CS1
BYP1
CS2
LDO5
FB1
Channel 1 Enable
Channel 2 Enable
EN1
EN2
VCLK
GND
PGOOD
LDO3
PGOOD Indicator
3.3V
5V
V
OUT2
V
OUT1
Copyright
©
2016 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS6576E-00 May 2016
www.richtek.com
1
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
