®
RT7739NC
SmartJitter
TM
Multi-Mode Flyback Controller
General Description
The RT7739NC is an enhanced high-efficiency multi-mode
PWM flyback controller, incorporating Richtek’s
proprietary SmartJitter
TM
technology. The innovative
SmartJitter
TM
technology can reduce EMI emissions of a
switch-mode power supply in green mode as well as
eliminate output ripple due to frequency jittering. Also,
the RT7739NC features a multi-mode control scheme,
operating from continuous-conduction mode (CCM) to
discontinuous-conduction mode (DCM) with valley
switching, to achieve high efficiency and optimal
performance.
The RT7739NC is a current-mode PWM controller for
flyback converters. It integrates comprehensive and
programmable protection features, which include
propagation delay compensation, output over-voltage
protection (OVP), external over-temperature protection
(OTP), and bulk-capacitor brown-in/brown-out protection.
With the above features, the RT7739NC enables a cost-
effective and compact design for a wide range of AC-DC
conversion applications. It is available in a SOT-23-6
package.
Features
Proprietary SmartJitter
TM
Technology
�½
Reducing EMI Emissions of SMPS
�½
Eliminating
Frequency-Jittering-Induced Output
Ripple
Operating in Continuous-Conduction Mode (CCM),
Discontinuous-Conduction Mode (DCM), DCM with
Valley-Switching
Ultra-low Start-Up Current (<3μA)
μ
Accurate Over-Current Protection (OCP)
Programmable Line Compensation
Programmable Output Over-Voltage Protection
Programmable External Over-Temperature Protection
Programmable Bulk-Capacitor Brown-In/Brown-Out
Protection
Driver Capability : 200mA/−300mA
−
High Noise Immunity
Applications
Switching AC-DC Adapter
NB Adapter
TV/Monitor Standby Power
PC Peripherals
Simplified Application Circuit
V
O+
Mains
(90V to 265V)
V
O-
(Option)
DMAG
VDD
GATE
CS
COMP
RT7739NC
C
COMP
GND
Copyright
©
2019 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS7739NC-00
January 2019
www.richtek.com
1
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
